Can supervise: YES
Al-Shetwi, AQ, Hannan, MA, Jern, KP, Mansur, M & Mahlia, TM 2020, 'Grid-connected renewable energy sources: Review of the recent integration requirements and control methods', JOURNAL OF CLEANER PRODUCTION, vol. 253.View/Download from: Publisher's site
Hannan, MA, Ali, JA, Hossain Lipu, MS, Mohamed, A, Ker, PJ, Indra Mahlia, TM, Mansor, M, Hussain, A, Muttaqi, KM & Dong, ZY 2020, 'Role of optimization algorithms based fuzzy controller in achieving induction motor performance enhancement.', Nature communications, vol. 11, no. 1, p. 3792.View/Download from: Publisher's site
Three-phase induction motors (TIMs) are widely used for machines in industrial operations. As an accurate and robust controller, fuzzy logic controller (FLC) is crucial in designing TIMs control systems. The performance of FLC highly depends on the membership function (MF) variables, which are evaluated by heuristic approaches, leading to a high processing time. To address these issues, optimisation algorithms for TIMs have received increasing interest among researchers and industrialists. Here, we present an advanced and efficient quantum-inspired lightning search algorithm (QLSA) to avoid exhaustive conventional heuristic procedures when obtaining MFs. The accuracy of the QLSA based FLC (QLSAF) speed control is superior to other controllers in terms of transient response, damping capability and minimisation of statistical errors under diverse speeds and loads. The performance of the proposed QLSAF speed controller is validated through experiments. Test results under different conditions show consistent speed responses and stator currents with the simulation results.
Hannan, MA, Begum, RA, Al-Shetwi, AQ, Ker, PJ, Al Mamun, MA, Hussain, A, Basri, H & Mahlia, TMI 2020, 'Waste collection route optimisation model for linking cost saving and emission reduction to achieve sustainable development goals', Sustainable Cities and Society, vol. 62.View/Download from: Publisher's site
© 2020 Elsevier Ltd Developing an efficient, cost-effective and environmentally friendly solution for solid waste collection (SWC) and transportation system remains a major challenge for municipalities. Waste collection encompasses the largest part of the total budget in current waste management systems. SWC is a crosscutting issue that can be directly or indirectly linked to 10 of the 17 United Nations' sustainable development goals (SDGs). This study aims to develop an SWC route optimisation model to improve collection efficiency, save collection costs and reduce emissions by considering fixed routing optimisation (FRO) with static data and variable routing optimisation (VRO) with real-time data. To realise the optimisation, a mixed-integer linear programming model utilising FRO and VRO was developed. Results show that VRO improved the collection efficiency by 26.08 % when the minimum filled-up level for collection was 70 %. Moreover, VRO achieved 44.44 % cost savings and 17.60 % carbon emission reduction at 70 % filled level. The proposed system achieved the targeted goals and demonstrated the feasibility of an optimisation model for the waste management sector to build a sustainable smart city. The findings of this study can be used to strengthen efforts towards the achievement of the SDGs related to solid waste collection and management.
Hannan, MA, Lipu, MSH, Hussain, A, Ker, PJ, Mahlia, TMI, Mansor, M, Ayob, A, Saad, MH & Dong, ZY 2020, 'Toward Enhanced State of Charge Estimation of Lithium-ion Batteries Using Optimized Machine Learning Techniques', Scientific Reports, vol. 10, no. 1.View/Download from: Publisher's site
© 2020, The Author(s). State of charge (SOC) is a crucial index used in the assessment of electric vehicle (EV) battery storage systems. Thus, SOC estimation of lithium-ion batteries has been widely investigated because of their fast charging, long-life cycle, and high energy density characteristics. However, precise SOC assessment of lithium-ion batteries remains challenging because of their varying characteristics under different working environments. Machine learning techniques have been widely used to design an advanced SOC estimation method without the information of battery chemical reactions, battery models, internal properties, and additional filters. Here, the capacity of optimized machine learning techniques are presented toward enhanced SOC estimation in terms of learning capability, accuracy, generalization performance, and convergence speed. We validate the proposed method through lithium-ion battery experiments, EV drive cycles, temperature, noise, and aging effects. We show that the proposed method outperforms several state-of-the-art approaches in terms of accuracy, adaptability, and robustness under diverse operating conditions.
Helwani, Z, Ramli, M, Rusyana, A, Marlina, M, Fatra, W, Idroes, GM, Suhendra, R, Ashwie, V, Mahlia, TMI & Idroes, R 2020, 'Alternative briquette material made from palm stem biomass mediated by glycerol crude of biodiesel byproducts as a natural adhesive', Processes, vol. 8, no. 7.View/Download from: Publisher's site
© 2020 by the authors. Recently, the global population has increased sharply, unfortunately, the availability of fossil fuel resources has significantly decreased. This phenomenon has become an attractive issue for many researchers in the world so that various studies in the context of finding renewable energy are developing continuously. Relating to this challenge, this research has been part of scientific work in the context of preparing an energy briquette employing palm oil stems and glycerol crude of biodiesel byproducts as inexpensive and green materials easily found in the Riau province, Indonesia. Technically, the palm oil stems are used for the production of charcoal particles and the glycerol crude as an adhesive compound in the production of energy briquettes. The heating value of palm oil stem is 17,180 kJ/kg, which can be increased to an even higher value through a carbonization process followed by a densification process so that it can be used as a potential matrix to produce energy briquettes. In detail, this study was designed to find out several parameters including the eect of sieve sizes consisting of 60, 80, and 100 mesh, respectively, which are used for the preparation of charcoal particles as the main matrix for the manufacture of the briquettes; the eect of charcoal-adhesive ratios (wt) of 60:40, 70:30, and 80:20; and the eect of varied pressures of 100, 110, and 120 kg/cm2 on the briquette quality. The quality of the obtained briquettes is analyzed through the observation of important properties which involve the heating value and the compressive strength using Response Surface Methodology (RSM). The results showed that the produced briquettes had an optimum heating value of 30,670 kJ/kg, while their loaded charcoal particles resulted from the mesh sieve of 80, in which there was a charcoal loading of 53 g and it pressed at 93.1821 bar, whereas, the compressive strength value of the briquette was 100,608 kg/cm2, which loaded charcoal parti...
Helwani, Z, Ramli, M, Saputra, E, Bahruddin, B, Yolanda, D, Fatra, W, Idroes, GM, Muslem, M, Mahlia, TMI & Idroes, R 2020, 'Impregnation of CaO from Eggshell Waste with Magnetite as a Solid Catalyst (Fe3O4/CaO) for Transesterification of Palm Oil Off-Grade', CATALYSTS, vol. 10, no. 2.View/Download from: Publisher's site
Huang, Y, Mok, WC, Yam, YS, Zhou, JL, Surawski, NC, Organ, B, Chan, EFC, Mofijur, M, Mahlia, TMI & Ong, HC 2020, 'Evaluating in-use vehicle emissions using air quality monitoring stations and on-road remote sensing systems', Science of the Total Environment, vol. 740.View/Download from: Publisher's site
© 2020 Elsevier B.V. This study investigated real world in-use vehicle emissions using two regulatory techniques simultaneously, namely on-road remote sensing (RS) systems and air quality (AQ) monitoring stations, aiming to provide a full pollution profile from tailpipe to roadside and atmosphere. Two large AQ and RS datasets collected during 2012–2018 were analyzed. The effects of various emission control programmes on the trends of tailpipe emissions and air quality were evaluated. Correlations between tailpipe emissions and roadside and ambient air quality were also explored. The results showed a decreasing trend of NO2 at both roadside and ambient AQ stations from 2013 to 2016, which was attributed to the intensive implementation of a series of vehicle emissions control programmes. Although NO2 was decreasing, O3 was generally increasing for all AQ stations. AQ data showed that O3 had little correlation with either NO2 or NOx, but was mainly determined by NO2/NOx ratio. Roadside NO2/NOx ratio increased first and then decreased or stabilized after 2014, while ambient NO2/NOx ratio increased steadily. RS data showed that the overall NO decreased quickly during 2012–2015 and then decreased moderately after 2015. The decrease was mainly attributed to the effective NO reduction from LPG vehicles. However, diesel NO remained high and reduced relatively slowly during the study period. Gasoline vehicles were relatively clean compared with LPG and diesel vehicles. Finally, good correlations were demonstrated between NO measured by RS sites and NOx measured by roadside AQ stations, indicating that vehicle emissions were the major contributor to roadside NOx pollution. Ambient NOx emissions could be affected by various sources, leading to different correlation levels between RS and ambient AQ results.
Lau, AKS, Bilad, MR, Nordin, NAHM, Faungnawakij, K, Narkkun, T, Wang, DK, Mahlia, TMI & Jaafar, J 2020, 'Effect of membrane properties on tilted panel performance of microalgae biomass filtration for biofuel feedstock', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 120.View/Download from: Publisher's site
Lee, XJ, Ong, HC, Gan, YY, Chen, W-H & Mahlia, TMI 2020, 'State of art review on conventional and advanced pyrolysis of macroalgae and microalgae for biochar, bio-oil and bio-syngas production', ENERGY CONVERSION AND MANAGEMENT, vol. 210.View/Download from: Publisher's site
Logeswaran, J, Shamsuddin, AH, Silitonga, AS & Mahlia, TMI 2020, 'Prospect of using rice straw for power generation: a review', Environmental Science and Pollution Research, vol. 27, no. 21, pp. 25956-25969.View/Download from: Publisher's site
© 2020, Springer-Verlag GmbH Germany, part of Springer Nature. With the ever-increasing energy demands, fossil fuels are gradually depleting and eventually, these nonrenewable sources of energy will be exhausted. Hence, there is an urgent need to formulate alternative fuels that are both renewable and sustainable. Biomass is one of the reliable sources of energy because it is replenishable. Rice is the staple food in many countries, particularly in Asia. The number of paddy fields has increased tremendously over the years and is expected to increase in the future in response to the growing world population. This will lead to significant amounts of agricultural wastes annually, particularly rice straw. In some countries, open burning and soil incorporation are used to manage agricultural wastes. Open burning is the preferred method because it is inexpensive. However, this method is highly undesirable because of its detrimental impact on the environment resulting from the release of carbon dioxide and methane gas. Hence, it is important to develop an energy-harvesting method from rice straw for power generation. More studies need to be carried out on the availability and characteristics of rice straw as well as logistic analysis to assess the potential of rice straw for power generation. This paper is focused on reviewing studies pertaining to the characteristics and potential of rice straw for power generation, current rice straw management practices, and logistic analysis in order to develop a suitable energy-harvesting method from rice straw in Malaysia.
Mahlia, TMI, Syazmi, ZAHS, Mofijur, M, Abas, AEP, Bilad, MR, Ong, HC & Silitonga, AS 2020, 'Patent landscape review on biodiesel production: Technology updates', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 118.View/Download from: Publisher's site
Mofijur, M, Kusumo, F, Fattah, IMR, Mahmudul, HM, Rasul, MG, Shamsuddin, AH & Mahlia, TMI 2020, 'Resource Recovery from Waste Coffee Grounds Using Ultrasonic-Assisted Technology for Bioenergy Production', ENERGIES, vol. 13, no. 7.View/Download from: Publisher's site
Ong, HC, Mofijur, M, Silitonga, AS, Gumilang, D, Kusumo, F & Mahlia, TMI 2020, 'Physicochemical Properties of Biodiesel Synthesised from Grape Seed, Philippine Tung, Kesambi, and Palm Oils', ENERGIES, vol. 13, no. 6.View/Download from: Publisher's site
Pourzolfaghar, H, Abnisa, F, Daud, WMAW, Aroua, MK & Mahlia, TMI 2020, 'Catalyst Characteristics and Performance of Silica-Supported Zinc for Hydrodeoxygenation of Phenol', ENERGIES, vol. 13, no. 11.View/Download from: Publisher's site
Prasetyo, WD, Putra, ZA, Bilad, MR, Mahlia, TMI, Wibisono, Y, Nordin, NAH & Wirzal, MDH 2020, 'Insight into the Sustainable Integration of Bio- and Petroleum Refineries for the Production of Fuels and Chemicals', POLYMERS, vol. 12, no. 5.View/Download from: Publisher's site
Putra, N, Sandi, AF, Ariantara, B, Abdullah, N & Indra Mahlia, TM 2020, 'Performance of beeswax phase change material (PCM) and heat pipe as passive battery cooling system for electric vehicles', Case Studies in Thermal Engineering, vol. 21.View/Download from: Publisher's site
© 2020 The Authors. Increasing greenhouse gas (GHG) emissions in the atmosphere and the scarcity of fossil fuel sources have encouraged car manufacturers to develop more environmentally friendly electric vehicles (EVs). The technology advancements of EVs - those with battery systems in particular - have increased their travel distances. Therefore, increasing and maintaining the battery capacity is a key concern in the development of sustainable EVs. In this study, passive cooling systems were constructed with a heat pipe and phase change material (PCM), and their performances were investigated with battery simulators. The aim was to determine the effectiveness of the cooling system and to identify the optimal PCM (beeswax or Rubitherm RT 44 HC) for a temperature range of 25-55 °C. The use of a heat pipe could decrease the battery temperature by 26.62 °C under a 60 W heat load compared to the case without passive cooling system. Furthermore, the addition of RT 44 to a heat pipe resulted in a maximal temperature decrease of 33.42 °C. Thus, an RT 44 HC is more effective than beeswax because its melting temperature lies within the recommended range of the battery working temperature, and its latent heat allows the absorption of more heat compared to beeswax.
Rizwanul Fattah, IM, Ong, HC, Mahlia, TMI, Mofijur, M, Silitonga, AS, Rahman, SMA & Ahmad, A 2020, 'State of the Art of Catalysts for Biodiesel Production', FRONTIERS IN ENERGY RESEARCH, vol. 8.View/Download from: Publisher's site
Silitonga, AS, Shamsuddin, AH, Mahlia, TM, Milano, J, Kusumo, F, Siswantoro, J, Dharma, S, Sebayang, AH, Masjuki, HH & Ong, HC 2020, 'Biodiesel synthesis from Ceiba pentandra oil by microwave irradiation-assisted transesterification: ELM modeling and optimization', RENEWABLE ENERGY, vol. 146, pp. 1278-1291.View/Download from: Publisher's site
Sukor, NR, Shamsuddin, AH, Mahlia, TMI & Isa, MFM 2020, 'Techno-Economic Analysis of CO2 Capture Technologies in Offshore Natural Gas Field: Implications to Carbon Capture and Storage in Malaysia', PROCESSES, vol. 8, no. 3.View/Download from: Publisher's site
Suryani, S, Sariani, S, Earnestly, F, Marganof, M, Rahmawati, R, Sevindrajuta, S, Mahlia, TMI & Fudholi, A 2020, 'A Comparative Study of Virgin Coconut Oil, Coconut Oil and Palm Oil in Terms of Their Active Ingredients', PROCESSES, vol. 8, no. 4.View/Download from: Publisher's site
Waqas, S, Bilad, MR, Man, Z, Wibisono, Y, Jaafar, J, Indra Mahlia, TM, Khan, AL & Aslam, M 2020, 'Recent progress in integrated fixed-film activated sludge process for wastewater treatment: A review', Journal of Environmental Management, vol. 268.View/Download from: Publisher's site
© 2020 Elsevier Ltd Integrated fixed-film activated sludge (IFAS) process is considered as one of the leading-edge processes that provides a sustainable solution for wastewater treatment. IFAS was introduced as an advancement of the moving bed biofilm reactor by integrating the attached and the suspended growth systems. IFAS offers advantages over the conventional activated sludge process such as reduced footprint, enhanced nutrient removal, complete nitrification, longer solids retention time and better removal of anthropogenic composites. IFAS has been recognized as an attractive option as stated from the results of many pilot and full scales studies. Generally, IFAS achieves >90% removals for combined chemical oxygen demand and ammonia, improves sludge settling properties and enhances operational stability. Recently developed IFAS reactors incorporate frameworks for either methane production, energy generation through algae, or microbial fuel cells. This review details the recent development in IFAS with the focus on the pilot and full-scale applications. The microbial community analyses of IFAS biofilm and floc are underlined along with the special emphasis on organics and nitrogen removals, as well as the future research perspectives.
Abas, PE & Mahlia, TMI 2019, 'Techno-economic and sensitivity analysis of rainwater harvesting system as alternative water source', Sustainability (Switzerland), vol. 11, no. 8.View/Download from: Publisher's site
© 2019 by the authors. This paper formulates a rainwater harvesting model, with system and economic measures to determine the feasibility of a rainwater harvesting system, which uses water from the mains to complement the system. Although local meteorological and market data were used to demonstrate the model, it can also be easily adapted for analysis of other localities. Analysis has shown that an optimum tank size exists, which minimizes the cost per unit volume of water. Economic performance measures have indicated that rainwater harvesting system is currently infeasible to be implemented in Brunei; with capital cost and water price being shown to be among the prohibiting factors. To improve feasibility, a combination of rebate scheme on capital cost and raising the current water price has been proposed. It has also been shown that the system is more viable for households with high water demand.
Abnisa, F, Anuar Sharuddin, SD, Bin Zanil, MF, Wan Daud, WMA & Mahlia, TMI 2019, 'The Yield Prediction of Synthetic Fuel Production from Pyrolysis of Plastic Waste by Levenberg-Marquardt Approach in Feedforward Neural Networks Model.', Polymers, vol. 11, no. 11.View/Download from: Publisher's site
The conversion of plastic waste into fuel by pyrolysis has been recognized as a potential strategy for commercialization. The amount of plastic waste is basically different for each country which normally refers to non-recycled plastics data; consequently, the production target will also be different. This study attempted to build a model to predict fuel production from different non-recycled plastics data. The predictive model was developed via Levenberg-Marquardt approach in feed-forward neural networks model. The optimal number of hidden neurons was selected based on the lowest total of the mean square error. The proposed model was evaluated using the statistical analysis and graphical presentation for its accuracy and reliability. The results showed that the model was capable to predict product yields from pyrolysis of non-recycled plastics with high accuracy and the output values were strongly correlated with the values in literature.
Adanta, D, Budiarso, Warjito & Mahlia, TMI 2019, 'Investigation of the effect of gaps between the blades of open flume Pico hydro turbine runners', Journal of Mechanical Engineering and Sciences, vol. 13, no. 3, pp. 5493-5512.
This study will analyze the impact of gap size in two different runners called runner A (five blades) and B (six blades) to provides recommendations in design and manufacture of open flume turbine runners so that maximize the conversion of kinetic and potential energy. There are three methods was used to investigate its: analytical method is used to design the turbine; experimental to determine the actual turbine performance; computational fluid dynamics (CFD) to study the physical phenomena and re-check the velocity triangle on the runner to validate the design and manufacturing process. Using the results obtained, gaps between the blades can alter the velocity vector on the outlet and unbalance the rotation of runner; this imbalance could cause cavitation. Then, the decreasing torque is assumed because water pressure in the draft tube is similar to atmospheric pressure. Two conditions must be satisfied to maximize the performance of the turbine: swirling flow is required after the water flows past the runner in order to minimize the radial velocity on the outlet so that the draft tube can function properly; the dimensions of the blade must be carefully selected to avoid the formation of gaps between the blades.
Antariksawan, AR, Widodo, S, Juarsa, M, Ismarwanti, S, Saptoadi, D, Kusuma, MH, Ardiyati, T & Mahlia, TMI 2019, 'Experimental and numerical simulation investigation of single-phase natural circulation in a large scale rectangular loop', Atom Indonesia, vol. 45, no. 1, pp. 17-25.View/Download from: Publisher's site
© 2019 Atom Indonesia. In order to anticipate station blackout, the use of safety system based on passive features is highly considered in advanced nuclear power plant designs, especially after the Fukushima Dai-ichi nuclear power station accident. An example is the application of natural circulation in the emergency cooling system. To study the reliability of such an application, a research project on natural circulation was carried out. This paper describes the investigation results on the natural circulation phenomena obtained using a large rectangular experimental loop named FASSIP-01. The experiments were conducted at two different heat source powers. The experimental results are analysed using existing correlation and numerical model simulation. The RELAP5 system code is applied to model the natural circulation. FLUENT computational fluid dynamic code is used to visualize the flow distribution. The experimental results show the establishment of stable natural circulation in all heat power input with the mass flow rate of about 0.0012 kg/s. Calculation using the existing correlation shows that the experimental Reynold numbers are lower than predicted by the correlation. The computational fluid dynamics-based tool could show the three dimensional distribution of the temperature, while the model of RELAP5 predict well the dynamic of the single-phase natural circulation established in the experimental loop. It is concluded that the stable natural circulation have been established in the large rectangular loop and the model of the RELAP5 could simulate the observed natural circulation phenomenon reasonably well.
Barambu, NU, Bilad, MR, Wibisono, Y, Jaafar, J, Mahlia, TMI & Khan, AL 2019, 'Membrane Surface Patterning as a Fouling Mitigation Strategy in Liquid Filtration: A Review', POLYMERS, vol. 11, no. 10.View/Download from: Publisher's site
Damanik, N, Ong, HC, Rahman, MM, Tong, CW, Silitonga, AS, Shamsuddin, AH, Sebayang, AH, Mahlia, TMI, Wang, CT & Jang, JH 2019, 'The performance and exhaust emissions of a diesel engine fuelled with Calophyllum inophyllum- palm biodiesel', Processes, vol. 7, no. 9.View/Download from: Publisher's site
© 2019 by the authors. Nowadays, increased interest among the scientific community to explore the Calophyllum inophyllum as alternative fuels for diesel engines is observed. This research is about using mixed Calophyllum inophyllum-palm oil biodiesel production and evaluation that biodiesel in a diesel engine. The Calophyllum inophyllum-palm oil methyl ester (CPME) is processed using the following procedure: (1) the crude Calophyllum inophyllum and palm oils are mixed at the same ratio of 50:50 volume %, (2) degumming, (3) acid-catalysed esterification, (4) purification, and (5) alkalinecatalysed transesterification. The results are indeed encouraging which satisfy the international standards, CPME shows the high heating value (37.9 MJ/kg) but lower kinematic viscosity (4.50 mm2/s) due to change the fatty acid methyl ester (FAME) composition compared to Calophyllum inophyllum methyl ester (CIME). The average results show that the blended fuels have higher Brake Specific Fuel Consumption (BSFC) and NOx emissions, lower Brake Thermal Efficiency (BTE), along with CO and HC emissions than diesel fuel over the entire range of speeds. Among the blends, CPME5 offered better performance compared to other fuels. It can be recommended that the CPME blend has great potential as an alternative fuel because of its excellent characteristics, better performance, and less harmful emission than CIME blends.
Fatimah, I, Sahroni, I, Fadillah, G, Musawwa, MM, Mahlia, TMI & Muraza, O 2019, 'Glycerol to solketal for fuel additive: Recent progress in heterogeneous catalysts', Energies, vol. 12, no. 15.View/Download from: Publisher's site
© 2019 by the authors. Biodiesel has been successfully commercialized in numerous countries. Glycerol, as a byproduct in biodiesel production plant, has been explored recently for fuel additive production. One of the most prospective fuel additives is solketal, which is produced from glycerol and acetone via an acetalization reaction. This manuscript reviewed recent progress on heterogeneous catalysts used in the exploratory stage of glycerol conversion to solketal. The effects of acidity strength, hydrophobicity, confinement effect, and others are discussed to find the most critical parameters to design better catalysts for solketal production. Among the heterogeneous catalysts, resins, hierarchical zeolites, mesoporous silica materials, and clays have been explored as effective catalysts for acetalization of glycerol. Challenges with each popular catalytic material are elaborated. Future works on glycerol to solketal will be improved by considering the stability of the catalysts in the presence of water as a byproduct. The presence of water and salt in the feed is certainly destructive to the activity and the stability of the catalysts.
Goh, BHH, Ong, HC, Cheah, MY, Chen, WH, Yu, KL & Mahlia, TMI 2019, 'Sustainability of direct biodiesel synthesis from microalgae biomass: A critical review', Renewable and Sustainable Energy Reviews, vol. 107, pp. 59-74.View/Download from: Publisher's site
© 2019 Elsevier Ltd Microalgae has been identified as a potential feedstock for biodiesel production since its cultivation requires less cropland compared to conventional oil crops and the high growth rate of microalgae. Research on microalgae oils often are focused on microalgae oil extraction and biomass harvesting techniques. However, energy intensive and costly lipid extraction methods are the major obstacles hampering microalgae biodiesel commercialisation. Direct biodiesel synthesis avoids such problems as it combines lipid extraction techniques and transesterification into a single step. In this review, the potential of direct biodiesel synthesis from microalgae biomass was comprehensively analysed. The various species of microalgae commonly used as biodiesel feedstock was critically assessed, particularly on high lipid content species. The production of microalgae biodiesel via direct conversion from biomass was systematically discussed, covering major enhancements such as heterogeneous catalysts, the use of ultrasonic and microwave- techniques and supercritical alcohols that focus on the overall improvement of biodiesel production. In addition, this review illustrates the cultivation conditions for biomass growth and lipid productivity improvement, the available harvesting and lipid extraction technologies, as well as the key challenges and future prospect of microalgae biodiesel production. This review serves as a basis for future research on direct biodiesel synthesis from modified microalgae biomass to improve profitability of microalgae biodiesel.
Hossain, N & Mahlia, TMI 2019, 'Progress in physicochemical parameters of microalgae cultivation for biofuel production.', Critical Reviews in Biotechnology, vol. 39, no. 6, pp. 835-859.View/Download from: Publisher's site
Microalgae have been exploited for biofuel generation in the current era due to its enormous energy content, fast cellular growth rate, inexpensive culture approaches, accumulation of inorganic compounds, and CO2 sequestration. Currently, research is ongoing towards the advancement of the microalgae cultivation parameters to enhance the biomass yield. The main objective of this study was to delineate the progress of physicochemical parameters for microalgae cultivation such as gaseous transfer, mixing, light demand, temperature, pH, nutrients and the culture period. This review demonstrates the latest research trends on mass transfer coefficient of different microalgae culturing reactors, gas velocity optimization, light intensity, retention time, and radiance effects on microalgae cellular growth, temperature impact on chlorophyll production, and nutrient dosage ratios for cellulosic metabolism to avoid nutrient deprivation. Besides that, cultivation approaches for microalgae associated with mathematical modeling for different parameters, mechanisms of microalgal growth rate and doubling time have been elaborately described. Along with that, this review also documents potential lipid-carbohydrate-protein enriched microalgae candidates for biofuel, biomass productivity, and different cultivation conditions including open-pond cultivation, closed-loop cultivation, and photobioreactors. Various photobioreactor types, the microalgae strain, productivity, advantages, and limitations were tabulated. In line with microalgae cultivation, this study also outlines in detail numerous biofuels from microalgae.
Background:Microalgae have been experimented as a potential feedstock for biofuel generation in current era owing to its' rich energy content, inflated growth rate, inexpensive culture approaches, the notable capacity of CO2 fixation, and O2 addition to the environment. Currently, research is ongoing towards the advancement of microalgal-biofuel technologies. The nano-additive application has been appeared as a prominent innovation to meet this phenomenon. Main text:The main objective of this study was to delineate the synergistic impact of microalgal biofuel integrated with nano-additive applications. Numerous nano-additives such as nano-fibres, nano-particles, nano-tubes, nano-sheets, nano-droplets, and other nano-structures' applications have been reviewed in this study to facilitate microalgae growth to biofuel utilization. The present paper was intended to comprehensively review the nano-particles preparing techniques for microalgae cultivation and harvesting, biofuel extraction, and application of microalgae-biofuel nano-particles blends. Prospects of solid nano-additives and nano-fluid applications in the future on microalgae production, microalgae biomass conversion to biofuels as well as enhancement of biofuel combustion for revolutionary advancement in biofuel technology have been demonstrated elaborately by this review. This study also highlighted the potential biofuels from microalgae, numerous technologies, and conversion processes. Along with that, the study recounted suitability of potential microalgae candidates with an integrated design generating value-added co-products besides biofuel production. Conclusions:Nano-additive applications at different stages from microalgae culture to end-product utilization presented strong possibility in mercantile approach as well as positive impact on the environment along with valuable co-products generation into the near future.
Hossain, N, Mahlia, TMI, Zaini, J & Saidur, R 2019, 'Techno-economics and Sensitivity Analysis of Microalgae as Commercial Feedstock for Bioethanol Production', Environmental Progress and Sustainable Energy, vol. 38, no. 5.View/Download from: Publisher's site
© 2019 American Institute of Chemical Engineers The foremost purpose of this techno-economic analysis (TEA) modeling was to predict a harmonized figure of comprehensive cost analysis for commercial bioethanol generation from microalgae species in Brunei Darussalam based on the conventional market scenario. This model was simulated to set out economic feasibility and probabilistic assumption for large-scale implementations of a tropical microalgae species, Chlorella vulgaris, for a bioethanol plant located in the coastal area of Brunei Darussalam. Two types of cultivation systems such as closed system (photobioreactor—PBR) and open pond approaches were anticipated for a total approximate biomass of 220 t year−1 on 6 ha coastal areas. The biomass productivity was 56 t ha−1 for PBR and 28 t ha−1 for pond annually. The plant output was 58.90 m3 ha−1 for PBR and 24.9 m3 ha−1 for pond annually. The total bioethanol output of the plant was 57,087.58 gal year−1 along with the value added by-products (crude bio-liquid and slurry cake). The total production cost of this project was US$2.22 million for bioethanol from microalgae and total bioethanol selling price was US$2.87 million along with the by-product sale price of US$1.6 million. A sensitivity analysis was conducted to forecast the uncertainty of this conclusive modeling. Different data sets through sensitivity analysis also presented positive impacts of economical and environmental views. This TEA model is expected to be initialized to determine an alternative energy and also minimize environmental pollution. With this current modeling, microalgal-bioethanol utilization mandated with gasoline as well as microalgae cultivation, biofuel production integrated with existing complementary industries, are strongly recommended for future applications. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019.
Hossain, N, Razali, AN, Mahlia, TMI, Chowdhury, A, Chowdhury, H, Ong, HC, Shamsuddin, AH & Silitonga, AS 2019, 'Experimental Investigation, Techno-Economic Analysis and Environmental Impact of Bioethanol Production from Banana Stem', ENERGIES, vol. 12, no. 20.View/Download from: Publisher's site
Banana stem is being considered as the second largest waste biomass in Malaysia. Therefore, the environmental challenge of managing this huge amount of biomass as well as converting the feedstock into value-added products has spurred the demand for diversified applications to be implemented as a realistic approach. In this study, banana stem waste was experimented for bioethanol generation via hydrolysis and fermentation methods with the presence of Saccharomyces cerevisiae (yeast) subsequently. Along with the experimental analysis, a realistic pilot scale application of electricity generation from the bioethanol has been designed by HOMER software to demonstrate techno-economic and environmental impact. During sulfuric acid and enzymatic hydrolysis, the highest glucose yield was 5.614 and 40.61 g/L, respectively. During fermentation, the maximum and minimum glucose yield was 62.23 g/L at 12 h and 0.69 g/L at 72 h, respectively. Subsequently, 99.8% pure bioethanol was recovered by a distillation process. Plant modeling simulated operating costs 65,980 US$/y, net production cost 869347 US$ and electricity cost 0.392 US$/kWh. The CO2 emission from bioethanol was 97,161 kg/y and SO2 emission was 513 kg/y which is much lower than diesel emission. The overall bioethanol production from banana stem and application of electricity generation presented the approach economically favorable and environmentally benign
Hossain, N, Zaini, J & Mahlia, TMI 2019, 'Experimental investigation of energy properties for Stigonematales sp. microalgae as potential biofuel feedstock', International Journal of Sustainable Engineering, vol. 12, no. 2, pp. 123-130.View/Download from: Publisher's site
© 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group. Microalgae has been considered potential biofuel source from the last decade owing to its versatile perspectives such as excellent capability of CO2 capture and sequestration, water treatment, prolific growth rate and enormous energy content. Thus, energy research on microalgae is being harnessed to mitigate CO2 and meet future energy demands. This study investigated the bioenergy potential of native blue-green microalgae consortium as initial energy research on microalgae in Brunei Darussalam. The local species of microalgae were assembled from rainwater drains, the species were identified as Stigonematales sp. and physical properties were characterised. Sundried biomass with moisture content ranging from 6.5% to 7.37% was measured to be used to determine the net and gross calorific value and they were 7.98 MJ/kg-8.57 MJ/kg and 8.70 MJ/kg-9.45 MJ/kg, respectively. Besides that, the hydrogen content, ash content, volatile matter, and bulk density were also experimented and they were 2.56%-3.15%, 43.6%-36.71%, 57–38%-63.29% and 661.2 kg/m3-673.07 kg/m3, respectively. Apart from experimental values, other physical bioenergy parameters were simulated and they were biomass characteristic index 61,822.29 kg/m3-62,341.3 kg/m3, energy density 5.27 GJ/m3-5.76G J/m3 and fuel value index 86.19–88.54. With these experimental results, microalgae manifested itself a potential source of biofuel feedstock for heat and electricity generation, a key tool to bring down the escalated atmospheric greenhouse gases and an alternation for fossil fuel.
Hossain, N, Zaini, J & Mahlia, TMI 2019, 'Life cycle assessment, energy balance and sensitivity analysis of bioethanol production from microalgae in a tropical country', Renewable and Sustainable Energy Reviews, vol. 115.View/Download from: Publisher's site
© 2019 Elsevier Ltd Overuse of petroleum and ongoing carbon-di-oxide (CO2) rise in the air of Brunei Darussalam has been emerged as a major environmental concern in this country. To resolve this issue, a comprehensive life cycle assessment (LCA) of alternative biofuel, bioethanol production from microalgae was demanded for realistic implementation. Therefore, LCA of bioethanol production from microalgae in terms of CO2 emission and energy balance was investigated based on the scenario of industrial-scale in Brunei Darussalam. This study demonstrated that 220 tons microalgae biomass was cultivated on 6 ha offshore lands for commercial bioethanol generation. The annual outcome of this commercial bioethanol plant has revealed net CO2 balance 218.86 ton. From the energy perspective, this study manifested itself as favourable with net energy ratio, 0.45 and net energy balance, −2749.6 GJ y−1. Apart from CO2 balance and energy generation aspect, the project demanded low water and land footprints. For photobioreactor cultivation, water and land footprints were 2 m3 GJ−1 and 2 m2 GJ−1, respectively as well as for open pond approach, they were 87 m3 GJ−1 and 13 m2 GJ−1, respectively. The project also presented microalgae growth supplements (phosphorus and nitrogen) accumulation possibilities from wastewater of manure and industries which is another positive aspect for benign environment. Overall, the commercial plant presented low CO2 emission, low land and water demand for microalgae cultivation, alternative eco-friendly and cheaper nutrients sources, quite high energy generation with main product and by-products. Thus, this study projected positive impact on energy and environmental aspects of microalgae-to-bioethanol conversion.
Hossain, N, Zaini, J, Mahlia, TMI & Azad, AK 2019, 'Elemental, morphological and thermal analysis of mixed microalgae species from drain water', Renewable Energy, vol. 131, pp. 617-624.View/Download from: Publisher's site
© 2018 Elsevier Ltd In this study, Stigonematales sp. microalgae were collected from drain water and characterized for its' morphological edifice, elemental composition, thermal condition and energy generation capacity by using scanning electron microscopy, energy dispersive X-ray, thermogravimetric analyzer and bomb calorimeter, respectively. Scanning electron micrographs revealed the top view of microalgae and ash pellet with carbon coated specimens at low voltage (5.0 kV) through the secondary electron image detector. Elemental analysis revealed all the major and minor constituents of this microalgae species and its' ash in terms of dry weight (%) and atomic weight (%). Thermogravimetric analysis was conducted at heating rate, 10 °C/min and this experimental results determined moisture content, volatile matter, ash content and fixed carbon of the sample with 4.5%, 35%, 39.5% and 21%, respectively. Microalgae powder blended with bituminous coal by 75%, 50% and 25% measured calorific value 14.07 MJ/kg, 19.88 MJ/kg and 26.42 MJ/kg, respectively. Microalgae (75%) -coal (25%) blend showed excellent amount of energy content, 24.59 MJ/kg. Microalgae blended with coal unveiled an outstanding outcome with elevation of the volatile matter and drop of the ash content. Optimization of microalgae-coal blend in large-scale application can initiate bright future in renewable energy exploration.
Idroes, R, Yusuf, M, Saiful, S, Alatas, M, Subhan, S, Lala, A, Muslem, M, Suhendra, R, Idroes, GM, Marwan, M & Mahlia, TMI 2019, 'Geochemistry exploration and geothermometry application in the North Zone of Seulawah Agam, Aceh Besar District, Indonesia', Energies, vol. 12, no. 23.View/Download from: Publisher's site
© 2019 MDPI AG. All rights reserved. Ageochemistry study has been done in four geothermal manifestations-Ie-Seu'um, Ie-Brôuk, Ie-Jue and the Van-Heutz crater-located in the north zone of Seulawah Agam mountain (Aceh Besar District, Indonesia). The study was performed through water and gas analysis. Water analysis were done for all geothermal manifestations, but gas analysis was only done for the Ie-Jue manifestation that has fumaroles. Cation and anion contents were analyzed by ion chromatography, ICP-OES, alkalimetry titrations, and spectrophotometry, meanwhile isotopes were measured by a Liquid Water Isotope Analyzer. The resulting data were used for fluid and gas geothermometry calculations, and plotted in a FT-CO2 Cross-Plot and a CH4-CO2-H2S triangle diagram to obtain reservoir temperatures. The data were also plotted by a Cl-HCO3-SO4 triangle and Piper diagram to obtain the water type and dominant chemical composition, a Na-K-Mg triangle diagram to obtain fluid equilibria, the isotope ratio in the stable isotope plot to obtain the origin of water, and a N2-He-Ar triangle diagram to establish the origin of fumaroles. The water analysis results showed that (1) Ie-Seu'um has an average reservoir temperature of 241.9 0.3 °C, a chloride water type, a dominant Na-K-Cl chemical composition, a mature water fluid equilibrium, and water of meteoric origin; (2) Ie-Brôuk has an average reservoir temperature of 321.95 13.4 °C, a bicarbonate water type, a dominant Na-Ca-HCO3chemical composition, an immature water fluid equilibrium, and water of meteoric origin; (3) Ie-Jue has an average reservoir temperature of 472.491.4 °C, a sulphate water type, a dominant Ca-SO4 chemical composition, an immature water fluid equilibrium and water of meteoric origin; and (4) the Van-Heutz crater has an average reservoir temperature of 439.395.3 °C, a sulphate water type, a dominant Ca-SO4 chemical composition, an immature water fluid equilibrium and water of magmatic origin. The results...
Jamaluddin, NAM, Riayatsyah, TMI, Silitonga, AS, Rahman, MM, Shamsuddin, AH, Ong, HC, Mahlia, TMI & Rahman, SMA 2019, 'Techno-economic analysis and physicochemical properties of Ceiba pentandra as second-generation biodiesel based on ASTM D6751 and EN 14214', Processes, vol. 7, no. 9.View/Download from: Publisher's site
© 2019 by the authors. Processing biodiesel from non-edible sources of feedstock seems to be thriving in recent years. It also has also gathered more attention than in the past, mainly because the biodiesel product is renewable and emits lower pollution compared to fossil fuels. Researchers have started their work on various kinds of biodiesel product, especially from a non-edible feedstock. Non-edible feedstocks such as Ceiba pentandra show great potential in the production of biodiesel, especially in the Southeast Asia region because the plants seem to be abundant in that region. Ceiba pentandra, also known as the Kapok tree, produces hundreds of pods with a length of 15 cm (5.9 in) and diameter 2-5 cm (1-2 in). The pods consist of seeds and fluffin the surrounding areas inside the pod, which itself contains yellowish fibre, a mixture of cellulose and lignin. The seeds of Ceiba pentandra can be used as feedstock for biodiesel production. The study for Ceiba pentandra will involve techno-economic, as well as a sensitivity analysis. Moreover, the study also shows that the techno-economic analysis of a biodiesel processing plant for 50 ktons Ceiba pentandra with a life span of 20 years is around $701 million with 3.7 years of the payback period. Besides that, this study also shows the differences in operating cost and oil conversion yield, which has the least impact on running cost. By improving the conversion processes continuously and by increasing the operational effciency, the cost of production will decrease. In addition, the study also explains the differences of final price biodiesel and diesel fossil fuel, both showing dissimilar scenarios subsidy and taxation. Biodiesel has a subsidy of $0.10/L and $0.18/L with a total tax exemption of 15%. The value was obtained from the latest subsidy cost and diesel in Malaysia. Finally, further research is needed in order to fully utilize the use of Ceiba pentandra as one of the non-edible sources of biodiesel.
Kusuma, MH, Putra, N, Rosidi, A, Ismarwanti, S, Antariksawan, AR, Ardiyati, T, Juarsa, M & Mahlia, TMI 2019, 'Investigation on the Performance of a Wickless-Heat Pipe Using Graphene Nanofluid for Passive Cooling System', Atom Indonesia, vol. 45, no. 3, pp. 173-182.View/Download from: Publisher's site
To enhance the thermal safety in case of station blackout, a wickless-heat pipe is proposed as an alternative passive cooling system technology to remove decay heat generation in the nuclear spent fuel storage pool. The objectives of this research are to investigate the heat transfer phenomena in vertical straight wickless-heat pipe using Graphene nanofluid working fluid and to study the effect of Graphene nanofluid on the vertical straight wickless-heat pipe thermal performance. The investigation was conducted in 6 meters height and 0.1016 m inside diameter of vertical straight wickless-heat pipe. In this research, the Graphene nanofluid with 1 % of weight concentration was used as working fluid. The effect of working fluid filling ratio, evaporator heat load, and coolant volumetric flow rate on the water jacket were studied. The results showed that the heat transfer phenomena, which were indicated by an overshoot, zigzag, and stable state, were observed. Based on thermal resistance obtained, it was shown that the vertical straight wickless-heat pipe charged with the Graphene nanofluid has a lower thermal resistance compared to one with demineralized water. The thermal resistance of vertical straight wickless-heat pipe using Graphene nanofluid and demineralized water were 0.015 °C/W and 0.016 °C/W, respectively. While the best thermal performance was achieved at a filing ratio of 80 %, higher heat load, and higher coolant volumetric flow rate. It can be concluded that Graphene nanofluid could enhance the thermal performance of vertical straight wickless-heat pipe.
Kusumo, F, Mahlia, TMI, Shamsuddin, AH, Ong, HC, Ahmad, AR, Ismail, Z, Ong, ZC & Silitonga, AS 2019, 'The effect of multi-walled carbon nanotubes-additive in physicochemical property of rice brand methyl ester: Optimization analysis', Energies, vol. 12, no. 17.View/Download from: Publisher's site
© 2019 by the authors. Biodiesel as an alternative to diesel fuel produced from vegetable oils or animal fats has attracted more and more attention because it is renewable and environmentally friendly. Compared to conventional diesel fuel, biodiesel has slightly lower performance in engine combustion due to the lower calorific value that leads to lower power generated. This study investigates the effect of multi-walled carbon nanotubes (MWCNTs) as an additive to the rice bran methyl ester (RBME). Artificial neural network (ANN) and response surface methodology (RSM) was used for predicting the calorific value. The interaction effects of parameters such as dosage of MWCNTs, size of MWCNTs and reaction time on the calorific value of RBME were studied. Comparison of RSM and ANN performance was evaluated based on the correlation coefficient (R2), the root mean square error (RMSE), the mean absolute percentage error (MAPE), and the average absolute deviation (AAD) showed that the ANN model had better performance (R2 = 0.9808, RMSE = 0.0164, MAPE = 0.0017, AAD = 0.173) compare to RSM (R2 = 0.9746, RMSE = 0.0170, MAPE = 0.0028, AAD = 0.279). The optimum predicted of RBME calorific value that is generated using the cuckoo search (CS) via lévy flight optimization algorithm is 41.78 (MJ/kg). The optimum value was obtained using 64 ppm of < 7 nm MWCNTs blending for 60 min. The predicted calorific value was validated experimentally as 41.05 MJ/kg. Furthermore, the experimental results have shown that the addition of MWCNTs was significantly increased the calorific value from 36.87 MJ/kg to 41.05 MJ/kg (11.6%). Also, the addition of MWCNTs decreased flashpoint (−18.3%) and acid value (−0.52%). As a conclusion, adding MWCNTs as an additive had improved the physicochemical properties characteristics of RBME. To our best knowledge, no research has yet been performed on the effect of multi-walled carbon nanotubes-additive in physicochemical property of rice brand methyl ester app...
Mahlia, TMI, Ismail, N, Hossain, N, Silitonga, AS & Shamsuddin, AH 2019, 'Palm oil and its wastes as bioenergy sources: a comprehensive review.', Environmental Science and Pollution Research, vol. 26, no. 15, pp. 14849-14866.View/Download from: Publisher's site
Due to global warming and increasing price of fossil fuel, scientists all over the world have been trying to find reliable alternative fuels. One of the most potential candidates is renewable energy from biomass. The race for renewable energy from biomass has long begun and focused on to combat the deteriorating condition of the environment. Palm oil has been in the spotlight as an alternative of bioenergy sources to resolve fossil fuel problem due to its environment-friendly nature. This review will look deep into the origins of palm oil and how it is processed, bioproducts from this biomass, and oil palm biomass-based power plant in Malaysia. Palm oil is usually processed from oil palm fruits and other parts of the oil palm plant are candidates for raw material of bioproduct generation. Oil palm biomass can be turned into three subcategories: bioproduct, biofuels, and biopower. Focusing on biofuel, the biodiesel from palm oil will be explored in detail and its implication in Malaysia as one of the biggest producers of oil palm in the world will also be emphasized comprehensively. The paper presents the detail of a schematic flow diagram of a palm oil mill process of transforming oil palm into crude palm oil and it wastes. This paper will also discuss the current oil palm biomass power plants in Malaysia. Palm oil has been proven itself as a potential alternative to reduce negative environmental impact of global warming.
Mahlia, TMI, Syaheed, H, Abas, AEP, Kusumo, F, Shamsuddin, AH, Ong, HC & Bilad, MR 2019, 'Organic Rankine Cycle (ORC) System Applications for Solar Energy: Recent Technological Advances', ENERGIES, vol. 12, no. 15.View/Download from: Publisher's site
Majeed, K, Ahmed, A, Abu Bakar, MS, Indra Mahlia, TM, Saba, N, Hassan, A, Jawaid, M, Hussain, M, Iqbal, J & Ali, Z 2019, 'Mechanical and Thermal Properties of Montmorillonite-Reinforced Polypropylene/Rice Husk Hybrid Nanocomposites', POLYMERS, vol. 11, no. 10.View/Download from: Publisher's site
Mat Nawi, NI, Bilad, MR, Zolkhiflee, N, Nordin, NAH, Lau, WJ, Narkkun, T, Faungnawakij, K, Arahman, N & Mahlia, TMI 2019, 'Development of A Novel Corrugated Polyvinylidene difluoride Membrane via Improved Imprinting Technique for Membrane Distillation.', Polymers, vol. 11, no. 5.View/Download from: Publisher's site
Membrane distillation (MD) is an attractive technology for desalination, mainly because its performance that is almost independent of feed solute concentration as opposed to the reverse osmosis process. However, its widespread application is still limited by the low water flux, low wetting resistance and high scaling vulnerability. This study focuses on addressing those limitations by developing a novel corrugated polyvinylidene difluoride (PVDF) membrane via an improved imprinting technique for MD. Corrugations on the membrane surface are designed to offer an effective surface area and at the same time act as a turbulence promoter to induce hydrodynamic by reducing temperature polarization. Results show that imprinting of spacer could help to induce surface corrugation. Pore defect could be minimized by employing a dual layer membrane. In short term run experiment, the corrugated membrane shows a flux of 23.1 Lm-2h-1 and a salt rejection of >99%, higher than the referenced flat membrane (flux of 18.0 Lm-2h-1 and similar rejection). The flux advantage can be ascribed by the larger effective surface area of the membrane coupled with larger pore size. The flux advantage could be maintained in the long-term operation of 50 h at a value of 8.6 Lm-2h-1. However, the flux performance slightly deteriorates over time mainly due to wetting and scaling. An attempt to overcome this limitation should be a focus of the future study, especially by exploring the role of cross-flow velocity in combination with the corrugated surface in inducing local mixing and enhancing system performance.
Mofijur, M, Hasan, MM, Mahlia, TMI, Rahman, SMA, Silitonga, AS & Ong, HC 2019, 'Performance and Emission Parameters of Homogeneous Charge Compression Ignition (HCCI) Engine: A Review', Energies, vol. 12, no. 18.View/Download from: Publisher's site
Mofijur, Mahlia, Logeswaran, Anwar, Silitonga, Rahman & Shamsuddin 2019, 'Potential of Rice Industry Biomass as a Renewable Energy Source', Energies, vol. 12, no. 21, pp. 4116-4116.View/Download from: Publisher's site
Fossil fuel depletion, along with its ever-increasing price and detrimental impact on the environment, has urged researchers to look for alternative renewable energy. Of all the options available, biomass presents a very reliable source due to its never-ending supply. As research on various biomasses has grown in recent years, waste from these biomasses has also increased, and it is now time to shift the focus to utilizing these wastes for energy. The current waste management system mainly focuses on open burning and soil incorporation as it is cost-effective; however, these affect the environment. There must be an alternative way, such as to use it for power generation. Rice straw and rice husk are examples of such potential biomass waste. Rice is the main food source for the world, mostly in Asian regions, as most people consume rice daily. This paper reviews factors that impact the implementation of rice-straw-based power plants. Ash content and moisture content are important properties that govern combustion, and these vary with location. Logistical improvements are required to reduce the transport cost of rice husk and rice straw, which is higher than the transportation cost of coal.
Nasruddin, Sholahudin, Satrio, P, Mahlia, TMI, Giannetti, N & Saito, K 2019, 'Optimization of HVAC system energy consumption in a building using artificial neural network and multi-objective genetic algorithm', Sustainable Energy Technologies and Assessments, vol. 35, pp. 48-57.View/Download from: Publisher's site
© 2019 Elsevier Ltd The optimization of heating, ventilating and air conditioning (HVAC) system operations and other building parameters intended to minimize annual energy consumption and maximize the thermal comfort is presented in this paper. The combination of artificial neural network (ANN) and multi-objective genetic algorithm (MOGA) is applied to optimize the two-chiller system operation in a building. The HVAC system installed in the building integrates radiant cooling system, variable air volume (VAV) chiller system, and dedicated outdoor air system (DOAS). Several parameters including thermostat setting, passive solar design, and chiller operation control are considered as decision variables. Subsequently, the percentage of people dissatisfied (PPD) and annual building energy consumption is chosen as objective functions. Multi-objective optimization is employed to optimize the system with two objective functions. As the result, ANN performed a good correlation between decision variables and the objective function. Moreover, MOGA successfully provides several alternative possible design variables to achieve optimum system in terms of thermal comfort and annual energy consumption. In conclusion, the optimization that considers two objectives shows the best result regarding thermal comfort and energy consumption compared to base case design.
Nurfahmi, Mofijur, M, Ong, HC, Jan, BM, Kusumo, F, Sebayang, AH, Husin, H, Silitonga, AS, Mahlia, TMI & Rahman, SMA 2019, 'Production Process and Optimization of Solid Bioethanol from Empty Fruit Bunches of Palm Oil Using Response Surface Methodology', PROCESSES, vol. 7, no. 10.View/Download from: Publisher's site
Ong, HC, Milano, J, Silitonga, AS, Hassan, MH, Shamsuddin, AH, Wang, C-T, Mahlia, TMI, Siswantoro, J, Kusumo, F & Sutrisno, J 2019, 'Biodiesel production from Calophyllum inophyllum-Ceiba pentandra oil mixture: Optimization and characterization', JOURNAL OF CLEANER PRODUCTION, vol. 219, pp. 183-198.View/Download from: Publisher's site
Putra, N, Hakim, II, Erwin, FP, Abdullah, NA, Ariantara, B, Amin, M, Mahlia, TMI & Kusrini, E 2019, 'Development of a novel thermoelectric module based device for thermal stability measurement of phase change materials', Journal of Energy Storage, vol. 22, pp. 331-335.View/Download from: Publisher's site
© 2019 Elsevier Ltd A recently developed method for the thermal stability measurement of phase-change materials (PCMs) involves thermal cycling using a thermoelectric module as a heating and cooling element. However, the utility of this approach was found to have some limitations, mainly because the thermoelectric polarity is changed according to time rather than the actual sample temperature. A method for thermal cycling test, where the thermoelectric polarity is automatically changed according to the sample temperature was developed in this study. In addition, a new cartridge design in this device requires a small sample volume (1.53 cm 3 ) and can be easily assembled and disassembled. This proposed device was tested on beeswax as a PCM sample. This is very important for savings PCMs material which usually expensive. The results showed that the apparatus had automatically cycled between the melting and cooling temperatures of beeswax. The thermal data showed that beeswax retains consistent melting and freezing temperatures after 1000 cycles, however, its heat of fusion degrades over repeated thermal cycling. This apparatus can be readily applied to study a wide range of PCMs for such as thermal energy storage materials for energy conservation. To our best knowledge, yet no study has been performed on this kind of equipment so far.
Putra, N, Rawi, S, Amin, M, Kusrini, E, Kosasih, EA & Mahlia, TMI 2019, 'Preparation of beeswax/multi-walled carbon nanotubes as novel shape-stable nanocomposite phase-change material for thermal energy storage', Journal of Energy Storage, vol. 21, pp. 32-39.View/Download from: Publisher's site
© 2018 Elsevier Ltd Development of phase-change material (PCM) as thermal energy storage for building envelopes is promising for energy utilization. However, there are two major drawbacks of PCM application, which are low thermal conductivity and high-volume reduction due to phase-change transition. One solution is to develop a shape-stabilized phase-change material (SSPCM) as a composite that is able to prevent leakage during the transition from solid to liquid. Therefore, the objective of this study is to prepare beeswax/multi-walled carbon nanotubes as form-stable nanocomposite phase-change material for thermal energy storage, based on previously unattempted methods. Beeswax was being used as PCM because of its high latent heat and multi-walled carbon nanotubes (MWCNTs) as supporting material with high thermal conductivity. There are three types of MWCNTs applied in this research: pristine MWCNTs, ball-milled MWCNTs and acid-treated MWCNTs. Beeswax/CNT composite samples were prepared with ratios of 5 and 20 wt%. Composite samples were tested from structure modification and thermal performance, including latent heat, sensible heat, melting point, solidifying point, thermal conductivity, and thermal-cycle testing for up to 300 cycles. Experimental results showed that thermal conductivity of novel shape-stable nanocomposite PCM increased by a factor of 2 and there was no significant phase transition in the melting or solidifying temperature. The high heat storage capability and thermal conductivity of nanocomposite PCM enable it to be a potential material for thermal energy storage in practical applications.
Rahman, MM, Mahlia, TMI, Silitonga, AS, Ong, HC, Silakhori, M, Hasan, MH, Putra, N & Ashrafur Rahman, SM 2019, 'Phase change materials (PCM) for solar energy usages and storage: An overview', Energies, vol. 12, no. 16.View/Download from: Publisher's site
© 2019 by the authors. Solar energy is a renewable energy source that can be utilized for different applications in today's world. The effective use of solar energy requires a storage medium that can facilitate the storage of excess energy, and then supply this stored energy when it is needed. An effective method of storing thermal energy from solar is through the use of phase change materials (PCMs). PCMs are isothermal in nature, and thus offer higher density energy storage and the ability to operate in a variable range of temperature conditions. This article provides a comprehensive review of the application of PCMs for solar energy use and storage such as for solar power generation, water heating systems, solar cookers, and solar dryers. This paper will benefit the researcher in conducting further research on solar power generation, water heating system, solar cookers, and solar dryers using PCMs for commercial development.
Rahman, SMA, Mahila, TM, Ahmad, A, Nabi, MN, Jafari, M, Dowell, A, Islam, MA, Marchese, AJ, Tryner, J, Brooks, PR, Bodisco, TA, Stevanovic, S, Rainey, T, Ristovski, ZD & Brown, RJ 2019, 'Effect of Oxygenated Functional Groups in Essential Oils on Diesel Engine Performance, Emissions, and Combustion Characteristics', ENERGY & FUELS, vol. 33, no. 10, pp. 9828-9834.View/Download from: Publisher's site
Rahmawati, R, Bilad, MR, Laziz, AM, Nordin, NAHM, Jusoh, N, Putra, ZA, Mahlia, TMI & Jaafar, J 2019, 'Finned spacer for efficient membrane fouling control in produced water filtration.', Journal of environmental management, vol. 249.View/Download from: Publisher's site
Membrane based technologies are highly reliable for water and wastewater treatment, including for removal of total oil and grease from produced water. However, performances of the pressure driven processes are highly restricted by membrane fouling and the application of traditional air bubbling system is limited by their low shear stress due to poor contacts with the membrane surface. This study develops and assesses a novel finned spacer, placed in between vertical panel, for membrane fouling control in submerged plate-and-frame module system for real produced water filtration. Results show that permeability of the panel is enhanced by 87% from 201 to 381 L/(m2 h bar). The spacer system can be operated in switching mode to accommodate two-sided panel aeration. This leads to panel permeability increment by 22% higher than the conventional vertical system. The mechanisms of finned spacer in encouraging the flow trajectory was proven by visual observation and flow simulation. The fins alter the air bubbles flow trajectory toward the membrane surface to effectively scour-off the foulant. Overall results demonstrate the efficacy of the developed spacer in projecting the air bubble trajectory toward the membrane surface and thus significantly enhances membrane panel productivity.
Sandu, S, Yang, M, Mahlia, TMI, Wongsapai, W, Ong, HC, Putra, N & Ashrafur Rahman, SM 2019, 'Energy-related CO2 emissions growth in ASEAN countries: Trends, drivers and policy implications', Energies, vol. 12, no. 24.View/Download from: Publisher's site
© 2019 by the authors. The primary objective of this paper is to analyse the growth of energy-related CO2 emissions in ASEAN (Association of Southeast Asian Nations), with specific emphasis on identifying its trends and underlying drivers. This objective is premised on the arguments that: (1) there is a general lack of analysis of energy-related CO2 emissions growth across ASEAN countries; and (2) such an analysis is critical, because it could enable an assessment to be made of the efficacy of existing energy policies for reducing emissions. Decomposition analysis is the main approach adopted in this paper. The findings of this paper suggest that the growth of energy-related CO2 emissions has slowed in some major emitters in the region, due to energy efficiency improvement, and, to a lesser extent, a gradual switch in energy fuel mix towards lower emission sources (gas and renewables). However, this improvement is unlikely to drive a major transformation in the energy sectors of the region to the extent considered adequate for redressing the challenge of rising emissions, as indicated by a steady emissions growth in most ASEAN countries over the entire study period (1971–2016). By implication, this suggests that a significant scale-up of existing policy effort is needed to rectify the situations.
Silitonga, AS, Mahlia, TMI, Kusumo, F, Dharma, S, Sebayang, AH, Sembiring, RW & Shamsuddin, AH 2019, 'Intensiﬁcation of Reutealis trisperma biodiesel production using infrared radiation: Simulation, optimisation and validation', Renewable Energy, vol. 133, pp. 520-527.View/Download from: Publisher's site
© 2018 Elsevier Ltd Biodiesel production using intensification of methyl ester is becoming very important due to its considerably lower energy requirement and shorter reaction time in obtaining feedstock oil. The present study investigated utilisation of Reutealis trisperma oil to produce biodiesel. A Box-Behnken experimental design was used to optimise the transesterification process. The process variables were explored and the optimum methanol to oil molar ratio, catalyst concentration, reaction temperature, and reaction time were 8:1, 1.2 wt%, 64 °C and 68 min respectively and the corresponding methyl ester yield was 98.39%. The experiment was conducted in triplicate to validate the quadratic model. Results showed average methyl ester yield was 97.78%, which is close to the predicted value, indicating reliability of the model. Results also indicated that using infrared radiation method has many advantageous, such as less energy consumption as a result of deeper penetration of reactant mass which can improve mass transfer between the immiscible reactants in order to improve quality of biodiesel. The physicochemical properties of Reutealis trisperma methyl ester produced under optimum transesterification process variables were also measured and the properties fulfilled the fuel specifications as per ASTM D6751 and EN 14214 standards.
Silitonga, AS, Mahlia, TMI, Shamsuddin, AH, Ong, HC, Milano, J, Kusumo, F, Sebayang, AH, Dharma, S, Ibrahim, H, Husin, H, Mofijur, M & Rahman, SMA 2019, 'Optimization of Cerbera manghas Biodiesel Production Using Artificial Neural Networks Integrated with Ant Colony Optimization', ENERGIES, vol. 12, no. 20.View/Download from: Publisher's site
Optimizing the process parameters of biodiesel production is the key to maximizing biodiesel yields. In this study, artificial neural network models integrated with ant colony optimization were developed to optimize the parameters of the two-step Cerbera manghas biodiesel production process: (1) esterification and (2) transesterification. The parameters of esterification and transesterification processes were optimized to minimize the acid value and maximize the C. manghas biodiesel yield, respectively. There was excellent agreement between the average experimental values and those predicted by the artificial neural network models, indicating their reliability. These models will be useful to predict the optimum process parameters, reducing the trial and error of conventional experimentation. The kinetic study was conducted to understand the mechanism of the transesterification process and, lastly, the model could measure the physicochemical properties of the C. manghas biodiesel.
Surindra, MD, Caesarendra, W, Prasetyo, T, Mahlia, TMI & Taufik 2019, 'Comparison of the Utilization of 110 degrees C and 120 degrees C Heat Sources in a Geothermal Energy System Using Organic Rankine Cycle (ORC) with R245fa, R123, and Mixed-Ratio Fluids as Working Fluids', PROCESSES, vol. 7, no. 2.View/Download from: Publisher's site
Abas, AEP & Mahlia, TMI 2018, 'Development of energy labels based on consumer perspective: Room air conditioners as a case study in Brunei Darussalam', ENERGY REPORTS, vol. 4, pp. 671-681.View/Download from: Publisher's site
Adnan, R, Sabri Adlan, Z, Munir, FA, Indra, TM & Masjuki, HH 2018, 'Effects of equivalence ratio on performance and emissions of diesel engine with hydrogen and water injection system at variable injection timing', International Journal of Mechanical and Mechatronics Engineering, vol. 18, no. 6, pp. 106-111.
© February 2018 IJENS. This paper aims to develop a comprehensive development and research for performance and emissions of diesel engine fueled with hydrogen and water at variable injection timing. Experiments have been conducted to compare the performance and emissions between diesel alone, diesel with hydrogen and hydrogen-diesel and water injection pressure. addition of hydrogen into diesel engine resulted in higher pressure which lead to huge indicated work. Furthermore, injecting water into diesel engine with hydrogen mixture indicated a desirable outcome. Existence of water in combustion slightly decreased the amount of emissions but opposite in term of performance. The fact is water injection exist in combustion will absorb a portion of heat release which will result low in combustion process thus lead to low in performance production otherwise production of NOx emission is low. In conclusion, humidification in combustion engine is a great idea toward a high performance and low in emissions production compared to diesel alone operation which leads to a green technology production.
Ahmed, A, Abu Bakar, MS, Azad, AK, Sukri, RS & Mahlia, TMI 2018, 'Potential thermochemical conversion of bioenergy from Acacia species in Brunei Darussalam: A review', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 82, pp. 3060-3076.View/Download from: Publisher's site
Damanik, N, Ong, HC, Tong, CW, Mahlia, TMI & Silitonga, AS 2018, 'A review on the engine performance and exhaust emission characteristics of diesel engines fueled with biodiesel blends.', Environmental science and pollution research international, vol. 25, no. 16, pp. 15307-15325.View/Download from: Publisher's site
Biodiesels have gained much popularity because they are cleaner alternative fuels and they can be used directly in diesel engines without modifications. In this paper, a brief review of the key studies pertaining to the engine performance and exhaust emission characteristics of diesel engines fueled with biodiesel blends, exhaust aftertreatment systems, and low-temperature combustion technology is presented. In general, most biodiesel blends result in a significant decrease in carbon monoxide and total unburned hydrocarbon emissions. There is also a decrease in carbon monoxide, nitrogen oxide, and total unburned hydrocarbon emissions while the engine performance increases for diesel engines fueled with biodiesels blended with nano-additives. The development of automotive technologies, such as exhaust gas recirculation systems and low-temperature combustion technology, also improves the thermal efficiency of diesel engines and reduces nitrogen oxide and particulate matter emissions.
Erwin, E, Surjosatyo, A, Nugroho, JS, Mahlia, TM & Soemardi, T 2018, 'The effect of hybrid savonius and darrieus turbine on the change of wake recovery and improvement of wind energy harvesting', Journal of Applied Engineering Science, vol. 16, no. 3, pp. 416-423.View/Download from: Publisher's site
© 2018 Institut za Istrazivanja. All rights reserved. The energy crisis encourages the development of renewable energy; one of the potential renewable energy is wind. In the field of wind turbine there is a two-way development of the utilization of wind energy, first by making a large wind turbine, the second by making a wind farm energy with a relatively small wind turbine.This hybrid VAWT wind turbine (Sultan Wind Turbine) is designed to work optimally on a farm array, on a wind turbine farm array will always cause a wake effect that will reduce overall wind turbine and farm array performance, an investigation with a CFD simulation is required to predict how far the wake effect will be before farm array build.The use of simulation software has been widely used to predict the effects of this wake, and experiments in the laboratory have also been done to predict the effects of a wake as well.This study'spurpose is to predict the distance area of the recovery wake behindthe wind turbine, this distance which will be the reference distance between wind turbine units and determining the density of the turbine in a farm. Simulation using Computational Fluid Dynamics (CFD), with a method of Multi Frame Reference (MRF). Analysis using descriptive and inferential method in statistics such as mean, Kolmogorov-Smirnov Z and KruskalWalis test.From the analysis of simulation results and data processing descriptively and analytic statistic, it can be concluded from the data given, the distance of x/D=4, wind speed has recovery to the value near the input speed and no significant change to x/D= 9. Then it can be concluded that the distance between two windturbines that can be used is a distance of 3.6 meters.These data suggest that the hybrid farm array VAWT savonius and darrieus have a higher power density compared to HAWT. From this power density calculation the hybrid VAWT has a greater electrical potential up to 300 percent compared to the HAWT farm array.
Hannan, MA, Faisal, M, Ker, PJ, Mun, LH, Parvin, K, Mahlia, TMI & Blaabjerg, F 2018, 'A review of internet of energy based building energy management systems: Issues and recommendations', IEEE Access, vol. 6, pp. 38997-39014.View/Download from: Publisher's site
© 2013 IEEE. A building energy management system (BEMS) is a sophisticated method used for monitoring and controlling a building's energy requirements. A number of potential studies were conducted in nearly or net zero energy buildings (nZEBs) for the optimization of building energy consumption through efficient and sustainable ways. Moreover, policy makers are approving measures to improve building energy efficiency in order to foster sustainable energy usages. However, the intelligence of existing BEMSs or nZEBs is inadequate, because of the static set points for heating, cooling, and lighting, the complexity of large amounts of BEMS data, data loss, and network problems. To solve these issues, a BEMS or nZEB solution based on the Internet of energy (IoE) provides disruptive opportunities for revolutionizing sustainable building energy management. This paper presents a critical review of the potential of an IoE-based BEMS for enhancing the performance of future generation building energy utilization. The detailed studies of the IoE architecture, typical nZEB configuration, different generations of nZEB, and smart building energy systems for future BEMS are investigated. The operations, advantages, and limitations of the existing BEMSs or nZEBs are illustrated. A comprehensive review of the different types of IoE-based BEMS technologies, such as energy routers, storage systems and materials, renewable sources, and plug-and-play interfaces, is then presented. The rigorous review indicates that existing BEMSs require advanced controllers integrated with IoE-based technologies for sustainable building energy usage. The main objective of this review is to highlight several issues and challenges of the conventional controllers and IoE applications of BEMSs or nZEBs. Accordingly, the review provides several suggestions for the research and development of the advanced optimized controller and IoE of future BEMSs. All the highlighted insights and recommendations of this...
Hossain, N, Zaini, J, Jalil, R & Mahlia, TMI 2018, 'The efficacy of the period of saccharification on oil palm (Elaeis guineensis) Trunk sap hydrolysis', International Journal of Technology, vol. 9, no. 4, pp. 652-662.View/Download from: Publisher's site
© IJTech 2018. This study investigates the enzymatic hydrolysis rate of Oil Palm (Elaeis guineensis) Trunk (OPT) sap in terms of the length of saccharification process with the aim to elevate sugar production. Emphasis was placed on the reaction time and addition of supplements such epsom salt (MgSO4) and alanine amino acid (C3H7NO2) to accelerate the efficiency of Saccharomyces cerevisiae containing the enzyme invertase. A whole oil palm trunk was divided into four different sections, upper, middle-1, middle-2 and bottom with separate experiments over 10 days enzymatic reaction period. The highest saccharification rate was shown as 13.47% on the tenth day. This result indicates that the increase in the saccharification rate was positively correlated with the length of hydrolysis. Moreover, the sample with nutrients achieved the highest sugar output, 17.91% on the fourth day of hydrolysis which was 4.44% higher than the hydrolysis rate of the sample without nutrients. In the presence of complex OPT sugars, together with other essential elements, epsom salt and alanine amino acid, S.cerevisiae achieved a higher hydrolysis metabolism to simple sugars as the cells strived to produce energy and regenerated the invertase. Moreover, the upper part of the OPT rendered the highest potential for sugar production with levels of 21.2% with supplements and 15.6% without. From this experimental analysis, a conventional saccharification method was optimized through the addition of nutrients and a prolonged (10 days) hydrolysis process which yielded an increase in sugar production.
Mahlia, TMI, Lim, JY, Aditya, L, Riayatsyah, TMI, Pg Abas, AE & Nasruddin 2018, 'Methodology for implementing power plant efficiency standards for power generation: potential emission reduction', Clean Technologies and Environmental Policy, vol. 20, no. 2, pp. 309-327.View/Download from: Publisher's site
© 2017, The Author(s). Some methods of generating power such as power generation through coal, natural gas, oil result in inevitable emissions of greenhouse gases. While power generation is necessary due to its increasing demand, it is important for power companies to generate their power in an efficient manner to reduce its effect on the environment. One of the most effective ways of tackling inefficiency issues is through the implementation of efficiency standard. While there exist a lot of studies addressing the topic of energy efficiency standards, there are very few papers that deal specifically with efficiency standard for power generation plant. This paper presents methodology for the implementation of power plant efficiency standard; as mandatory or voluntary regulatory instrument, that may be implemented by the government to control greenhouse emissions from power plants. It is hoped that through its implementation, power companies shall become more conscious of their efficiency and emission quality, hereby encouraging the adoption of more efficient energy sources and latest available technologies. In this paper, methods of calculating greenhouse intensity value and its corresponding allowable ranges have been demonstrated. Case study on a 10-year-old base-load multi-fuel-fired power plant in Malaysia has shown that the power plant is in conformance to the power plant efficiency standard, with an actual greenhouse intensity of 859.4461 kgCO2/MWh sent-out, well within the allowable range of greenhouse intensities for that power plant which is between 760 and 890 kgCO2/MWh sent-out. It has also been demonstrated that older power plants are allowed to have higher values of greenhouse intensity. Benefits of utilising natural gas and operating the power plant at full load have also been shown.
© 2018 Elsevier Ltd. All rights reserved. There is rising concern on the increasing trend of global warming due to anthropogenic CO2 emission which steers progress of carbon capture and storage (CCS) projects worldwide. However, due to high cost and uncertainties in long term geological storage, there is a growing inclination to include utilization, which re-use the CO2, hence carbon capture utilization and storage (CCUS). Additionally, it is expected to generate income to offset the initial costs. This study methodically review patents on CO2 utilization technologies for CCUS application published between year 1980-2017. It was conducted using the Derwent Innovation patent database and more than 3000 number of patents was identified. The patents identified are in the field of enhanced oil recovery (EOR) and enhanced coal-bed methane (ECBM), chemical and fuel, mineral carbonation, biological algae cultivation and enhanced geothermal system (EGS). Over 60% of these patents were published since the last 10 years, and a sharp increase in patents were seen in the last 5 years (∼38%). The top major patent types are patents granted in the United States (US), China (CN) and Canada (CA) which makes of 3/5 of the overall patent type found. Recent patents published include enhancements to the state-of-the-art technologies and hybrid concepts such as in photo-bioreactor in algae cultivation, chemical reaction and EGS. From this study, it was found that further research for the best CO2 utilization method which fulfil the need of an economic, safe, non-location dependent and environmentally friendly whilst efficiently mitigate the worldwide global warming issue is much needed.
Ratiko, R, Samudera, SA, Hindami, R, Siahaan, AT, Naldi, L, Hapsari, D, Mahlia, TMI & Nasruddin, N 2018, 'Optimization of dry storage for spent fuel from G.A. Siwabessy nuclear research reactor', International Journal of Technology, vol. 9, no. 1, pp. 55-67.View/Download from: Publisher's site
© IJTech 2018. This study proposes a method of optimizing the dry storage design for nuclear-spent fuel from the G.A. Siwabessy research reactor at National Nuclear Energy Agency of Indonesia (BATAN). After several years in a spent fuel pool storage (wet storage), nuclear spent fuel is often moved to dry storage. Some advantages of dry storage compared with wet storage are that there is no generation of liquid waste, no need for a complex and expensive purification system, less corrosion concerns and that dry storage is easier to transport if in the future the storage needs to be sent to the another repository or to the final disposal. In both wet and dry storage, the decay heat of spent fuel must be cooled to a safe temperature to prevent cracking of the spent fuel cladding from where hazardous radioactive nuclides could be released and harm humans and the environment. Three optimization scenarios including the thermal safety single-objective, the economic single-objective and the multi-objective optimizations are obtained. The optimum values of temperature and cost for three optimization scenarios are 317.8K (44.7°C) and 11638.1 US$ for the optimized single-objective thermal safety method, 337.1K (64.0°C) and 6345.2 US$ for the optimized single-objective cost method and 325.1K (52.0°C) and 8037.4 US$ for the optimized multi-objective method, respectively.
Silitonga, AS, Masjuki, HH, Ong, HC, Sebayang, AH, Dharma, S, Kusumo, F, Siswantoro, J, Milano, J, Daud, K, Mahlia, TMI, Chen, WH & Sugiyanto, B 2018, 'Evaluation of the engine performance and exhaust emissions of biodiesel-bioethanol-diesel blends using kernel-based extreme learning machine', Energy, vol. 159, pp. 1075-1087.View/Download from: Publisher's site
© 2018 Elsevier Ltd It is known that biodiesel and bioethanol are viable alternative fuels to replace diesel for compression ignition engines. In this study, an experimental investigation is carried out to evaluate the performance and exhaust emissions of a single cylinder diesel engine fuelled with biodiesel-bioethanol-diesel blends. The engine performance parameters evaluated are the brake speciﬁc fuel consumption and brake thermal efﬁciency whereas the exhaust emission parameters evaluated are carbon monoxide, nitrogen oxide, and smoke opacity. Kernel-based extreme learning machine is used to predict the engine performance and exhaust emission parameters of the fuel blends at full throttle conditions. Based on the experimental results, the brake specific fuel consumption is lower while the brake thermal efficiency is higher for the biodiesel-bioethanol-diesel blends. The carbon monoxide emissions and smoke opacity are also lower for these fuel blends. The mean absolute percentage error of the brake specific fuel consumption, brake thermal efficiency, carbon monoxide, nitrogen oxide, and smoke opacity is 1.363, 1.482, 4.597, 2.224, and 2.090%, respectively. Thus, it can be concluded that K-ELM is a reliable method to estimate the engine performance and exhaust emission parameters of a single cylinder compression ignition engine fuelled with biodiesel-bioethanol-diesel blends to reduce fuel consumption and exhaust emissions.
Thaib, R, Rizal, S, Hamdani, Mahlia, TMI & Pambudi, NA 2018, 'Experimental analysis of using beeswax as phase change materials for limiting temperature rise in building integrated photovoltaics', Case Studies in Thermal Engineering, vol. 12, pp. 223-227.View/Download from: Publisher's site
© 2018 The Authors. Indonesia has the potential of saving from 10% to 30% of energy in the commercial sector which consists of trade, hotels, restaurants, finances, government agencies, schools, hospitals, and communications. By simultaneously serving as building envelope material and power generator, BIPV systems can represent savings in the cost of materials and electricity. It reduce the use of fossil fuels and emission of ozone depleting gases, and also add architectural interest to buildings. However, the temperature rise poses a challenge for BIPV, given that it manifests itself in electrical efficiency and overheating. The experiments present in this study aim at understanding the behavior of the PV-PCM systems in realistic outdoor uncontrolled conditions to determine how effective they are. In addition, the PV-PCM systems were tried in the low latitude and hot climate of Banda Aceh, Indonesia. Experiments were conducted outdoors at the Engineering Faculty in Syiah Kuala University, located in Banda Aceh, Indonesia (05:57 N, 95.37 E). In this study, both paraffin wax and beeswax were used as a phase change material. The final results showed that the electrical efficiency of PV panels without PCM is ranged between 6.1% and 6.5%. While for PV panels with PCM the efficiency is ranged at 7.0-7.8%. This proved that the process of water cooling is capable of increasing the efficiency of PV panels.
Uddin, MN, Techato, K, Taweekun, J, Rahman, MM, Rasul, MG, Mahlia, TMI & Ashrafur, SM 2018, 'An Overview of Recent Developments in Biomass Pyrolysis Technologies', ENERGIES, vol. 11, no. 11.View/Download from: Publisher's site
Umar, H, Rizal, S, Riza, M & Mahlia, TMI 2018, 'Mechanical properties of concrete containing beeswax/dammar gum as phase change material for thermal energy storage', AIMS Energy, vol. 6, no. 3, pp. 521-529.View/Download from: Publisher's site
© 2018 the Author(s). This study aims to investigate the mechanical properties of concrete containing phase change materials (PCM). This research begins with the investigation of melting temperature, enthalpy, the thermal conductivity of the phase change materials using the T-history method, followed by preparation of concrete containing PCM, and finally testing of mechanical properties of concrete through compressive strength test. This study used beeswax, tallow, and dammar gum as PCM mixture. From the results of the PCM properties test, shows that the latent heat energy content from beeswax and tallow exhibit an excellent potential to be used as PCM, while dammar gum is benefited in increasing the thermal conductivity of concrete containing PCM. From concrete specimen test containing 10%, 20% and 30% PCM with 7 days and 28 days aged, the results exhibit that the mechanical properties of the concrete decreased along with the increasing of PCM content. The same test also conducted at the PCM melting temperature. Therefore, the concrete compressive strength test conducted at 45 °C. From the test results, the concrete compressive strength decreased about 3-24% of PCM-0% concrete compressive strength. Drastic compressive strength reduction tends to occur in PCM-Tallow concrete mixture. This study concluded that the PCM is potentially useful as a heat energy absorber material in buildings and lightweight concrete rather than construction structures.
Aditya, L, Mahlia, TMI, Rismanchi, B, Ng, HM, Hasan, MH, Metselaar, HSC, Muraza, O & Aditiya, HB 2017, 'A review on insulation materials for energy conservation in buildings', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 73, pp. 1352-1365.View/Download from: Publisher's site
Amin, M, Putra, N, Kosasih, EA, Prawiro, E, Luanto, RA & Mahlia, TMI 2017, 'Thermal properties of beeswax/graphene phase change material as energy storage for building applications', Applied Thermal Engineering, vol. 112, pp. 273-280.View/Download from: Publisher's site
© 2016 Elsevier Ltd Increased energy consumption in buildings is a worldwide issue. This research is concerned with the implementation of a phase change material for thermal storage. This concept has gained great attention as a solution to reduce energy consumption in buildings. Beeswax, which is a phase change material with a high thermal capacity, is investigated in this research. This paper is intended to measure and analyze the thermal properties of beeswax/graphene as a phase change material. The melting temperature, thermal capacity and latent heat were determined using differential scanning calorimetry (DSC), and the thermal conductivity was investigated using a thermal conductivity measurement apparatus. To discover the change in the physical properties due to the effect of nanoparticles, the viscosity of the material was investigated as well. Based on the result from the DSC, the latent heat of 0.3 wt% beeswax/graphene increased by 22.5%. The thermal conductivity of 0.3 wt% beeswax/graphene was 2.8 W/m K. The existence of graphene nanoplatelets enhanced both the latent heat and thermal conductivity of the beeswax. Therefore, based on this result, beeswax/graphene is concluded to have the potential to reduce energy consumption in buildings.
Hanif, M, Abu Bakar, MS & Mahlia, TMI 2017, 'Techno-economic and sensitivity analysis of bioethanol production from rice straw in Malaysia', WASTE MANAGEMENT, vol. 67, pp. I-II.View/Download from: Publisher's site
Hanif, M, Mahlia, TMI, Aditiya, HB & Bakar, MSA 2017, 'Energy and environmental assessments of bioethanol production from Sri Kanji 1 cassava in Malaysia', Biofuel Research Journal, vol. 4, no. 1, pp. 537-544.View/Download from: Publisher's site
© 2017 BRTeam. According to the Malaysia's biofuel policy, renewable fuels are crucial for energy sustainability in the transportation sector in the future. This study was aimed to evaluate the potential of bioethanol production from Sri Kanji 1 cassava in Malaysia in terms of energy efficiency and renewability, as well to estimate the potential greenhouse gas (GHG) emissions reduction in CO2equivalent. Bioethanol production process from cassava includes cassava farming, ethanol production, and transportation in which the primary energy consumption was considered. The Net Energy Balance (NEB) and Net Energy Ratio (NER) of 25.68 MJ/L and 3.98, respectively, indicated that bioethanol production from Sri Kanji 1 cassava in Malaysia was energy efficient. From the environmental perspective, the GHG balance results revealed that the production and distribution of 1 L of Cassava Fuel Ethanol (CFE) could reduce GHG emissions by 73.2%. Although found promising in the present study, Sri Kanji 1 cassava as bioethanol feedstock should be further investigated by constructing an actual ethanol plant to obtain real life data.
Hossain, N, Jalil, R, Mahlia, TMI & Zaini, J 2017, 'Calorific value analysis of Azadirachta excelsa and endospermum malaccense as potential solid fuels feedstock', International Journal of Technology, vol. 8, no. 4, pp. 634-643.View/Download from: Publisher's site
© IJTech 2017. Thermal conversion of woody biomass to fuel has been intensified in recent decades due to the depletion of fossil fuels, greenhouse effect and high energy demand worldwide. Screening the potential feedstock is being considered as one of the alternatives to identifying the most suitable biomass resources prior to being converted into renewable energy in the form of solid fuels, such as charcoal and briquettes. Generally, high calorific value (CV) indicates high potential of feedstock for briquettes, torrefied wood and coal generation. In this study, CV was characterized using a bomb calorimeter that was based on 3 different ranges of moisture content (MC) that are > 25%, 20%-25% and < 20% for two tropical tree species, namely Azadirachta excelsa (Sentang) and Endospermum malaccense (Sesenduk), respectively. This standard method for the characterization process was considered to determine the CV. Average CV for both samples ranged between 16-17 MJ/kg. The highest CV was 17.3490 MJ/kg and 17.1273 MJ/kg for Sesenduk and Sentang, respectively and calorific values were obtained at MC less than 20%. The experimental study demonstrated that the decreasing value of MC has increased the CV because of the high value of oxygen-to-carbon (O/C) ratio in the wood; additionally, the energy density of the wood sample was also improved when CV increased. Both of these species were proved to contain the potential of being feedstock as wood fuel resources, since they carry standard CVs, obtain fast growth with suitable conditions in Malaysia and are grown at very low cost of production for plantations, fertilizer, pesticides, labor, transportation and handling.
Hossain, N, Zaini, JH & Mahlia, TMI 2017, 'A review of bioethanol production from plant-based waste biomass by yeast fermentation', International Journal of Technology, vol. 8, no. 1, pp. 5-18.View/Download from: Publisher's site
© IJTech 2017. Commercialization of bioethanol has recently intensified due to its market stability, low cost, sustainability, alternative fuel energy composition, greener output and colossal fossil fuel depletion. Recently, because of greenhouse intensity worldwide, many researches are ongoing to reprocess the waste as well as turning down the environmental pollution. With this scenario, the invention of bioethanol was hailed as a great accomplishment to transform waste biomass to fuel energy and in turn reduce the massive usages of fossil fuels. In this study, our review enlightens various sources of plant-based waste feed stocks as the raw materials for bioethanol production because they do not adversely impact the human food chain. However, the cheapest and conventional fermentation method, yeast fermentation is also emphasized here notably for waste biomass-to-bioethanol conversion. Since the key fermenting agent, yeast is readily available in local and international markets, it is more cost-effective in comparison with other fermentation agents. Furthermore, yeast has genuine natural fermentation capability biologically and it produces zero chemical waste. This review also concerns a detailed overview of the biological conversion processes of lignocellulosic waste biomass-to-bioethanol, the diverse performance of different types of yeasts and yeast strains, plusbioreactor design, growth kinetics of yeast fermentation, environmental issues, integrated usages on modern engines and motor vehicles, as well as future process development planning with some novel co-products.
Kusumo, F, Silitonga, AS, Masjuki, HH, Ong, HC, Siswantoro, J & Mahlia, TMI 2017, 'Optimization of transesterification process for Ceiba pentandra oil: A comparative study between kernel-based extreme learning machine and artificial neural networks', Energy, vol. 134, pp. 24-34.View/Download from: Publisher's site
© 2017 Elsevier Ltd In this study, kernel-based extreme learning machine (K-ELM) and artificial neural network (ANN) models were developed in order to predict the conditions of an alkaline-catalysed transesterification process. The reliability of these models was assessed and compared based on the coefficient of determination (R2), root mean squared error (RSME), mean average percent error (MAPE) and relative percent deviation (RPD). The K-ELM model had higher R2(0.991) and lower RSME, MAPE and RPD (0.688, 0.388 and 0.380) compared to the ANN model (0.984, 0.913, 0.640 and 0.634). Based on these results, the K-ELM model is a more reliable prediction model and it was integrated with ant colony optimization (ACO) in order to achieve the highest Ceiba pentandra methyl ester yield. The optimum molar ratio of methanol to oil, KOH catalyst weight, reaction temperature, reaction time and agitation speed predicted by the K-ELM model integrated with ACO was 10:1, 1 %wt, 60 °C, 108 min and 1100 rpm, respectively. The Ceiba pentandra methyl ester yield attained under these optimum conditions was 99.80%. This novel integrated model provides insight on the effect of parameters investigated on the methyl ester yield, which may be useful for industries involved in biodiesel production.
Kusumo, F, Silitonga, AS, Ong, HC, Masjuki, HH & Mahlia, TMI 2017, 'A comparative study of ultrasound and infrared transesterification of Sterculia foetida oil for biodiesel production', ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS, vol. 39, no. 13, pp. 1339-1346.View/Download from: Publisher's site
Nurhadi, M, Chandren, S, Yuan, LS, Ho, CS, Mahlia, TMI & Nur, H 2017, 'Titania-Loaded Coal Char as Catalyst in Oxidation of Styrene with Aqueous Hydrogen Peroxide', INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING, vol. 15, no. 1, pp. 45-55.View/Download from: Publisher's site
Riayatsyah, TMI, Ong, HC, Chong, WT, Aditya, L, Hermansyah, H & Mahlia, TMI 2017, 'Life Cycle Cost and Sensitivity Analysis of Reutealis trisperma as Non-Edible Feedstock for Future Biodiesel Production', ENERGIES, vol. 10, no. 7.View/Download from: Publisher's site
Sebayang, AH, Hassan, MH, Ong, HC, Dharma, S, Silitonga, AS, Kusumo, F, Mahlia, TMI & Bahar, AH 2017, 'Optimization of reducing sugar production from Manihot glaziovii starch using response surface methodology', Energies, vol. 10, no. 1, pp. 1167-1175.View/Download from: Publisher's site
Bioethanol is known as a viable alternative fuel to solve both energy and environmental crises. This study used response surface methodology based on the Box-Behnken experimental design to obtain the optimum conditions for and quality of bioethanol production. Enzymatic hydrolysis optimization was performed with selected hydrolysis parameters, including substrate loading, stroke speed, α-amylase concentration and amyloglucosidase concentration. From the experiment, the resulting optimum conditions are 23.88% (w/v) substrate loading, 109.43 U/g α-amylase concentration, 65.44 U/mL amyloglucosidase concentration and 74.87 rpm stroke speed, which yielded 196.23 g/L reducing sugar. The fermentation process was also carried out, with a production value of 0.45 g ethanol/g reducing sugar, which is equivalent to 88.61% of ethanol yield after fermentation by using Saccharomyces cerevisiae (S. cerevisiae). The physical and chemical properties of the produced ethanol are within the specifications of the ASTM D4806 standard. The good quality of ethanol produced from this study indicates that Manihot glaziovii (M. glaziovii) has great potential as bioethanol feedstock.
Shekarchian, M, Moghavvemi, M, Zarifi, F, Moghavvemi, S, Motasemi, F & Mahlia, TMI 2017, 'Impact of infrastructural policies to reduce travel time expenditure of car users with significant reductions in energy consumption', Renewable and Sustainable Energy Reviews, vol. 77, pp. 327-335.View/Download from: Publisher's site
© 2017 Elsevier Ltd The increasing number of vehicles and drivers have led to a marked increase in travel time expenditure (TTE), congestion, demand for fossil fuels, and adverse environmental impacts. Improving energy efficiency in the transportation sector, public awareness of the behavior of the people vis-à-vis energy efficiency, implementing policies that encourage other modes of transportation (e.g., public transit, ride-sharing, bicycles, and walking, etc.) that decrease vehicle dependency are some effective approaches that mitigate the aforementioned negative effects, which will lead to significant reductions in the total energy consumption. This article investigates the effect of governmental policies on vehicle dependency reduction and the decrease of TTE by vehicle owners, and propose a novel method to calculate the current and future TTEs by individuals. The effect of demographic variables and the region on vehicle dependency and TTE for students of three of the most populated universities in Malaysia (University of Malaya, University Putra Malaysia, and University Technology Malaysia) were investigated as well. The peoples' expectations from individual modes of transportation such as cycling and walking were also analyzed. The results showed that all demographic factors, except nationality, affect the levels of vehicle ownership, while income levels and nationality affects TTE by personal vehicles. The results show that the average TTE can be reduced by 89% if the recommended infrastructure (e.g., increase bus routes, train routes, train services, frequencies of buses and train, and facilities for cyclists, etc.) is provided. These outcomes can assist policy makers to efficiently manage transportation budgets, and would also help people decrease vehicle usage, which will subsequently decrease their corresponding TTE and fuel consumption.
Silitonga, AS, Mahlia, TMI, Ong, HC, Riayatsyah, TMI, Kusumo, F, Ibrahim, H, Dharma, S & Gumilang, D 2017, 'A comparative study of biodiesel production methods for Reutealis trisperma biodiesel', Energy Sources, Part A: Recovery, Utilization and Environmental Effects, vol. 39, no. 20, pp. 2006-2014.View/Download from: Publisher's site
© 2017 Taylor & Francis Group, LLC. In this study, three types of biodiesel production methods are compared in order to maximize Reutealis trisperma biodiesel yields and it is found that the best method is esterification-neutralization-transesterification. The optimum methanol to oil molar ratio, catalyst concentration, reaction temperature, and reaction time are also determined from laboratory experiments and modeling using response surface methodology. There is excellent agreement between the predicted and experimental Reutealis trisperma biodiesel yields under optimum process conditions, with a value of 99.23 and 98.72%, respectively. The physicochemical properties of the Reutealis trisperma biodiesel also fulfill the fuel specifications of the ASTM D6751 standard.
Silitonga, AS, Masjuki, HH, Ong, HC, Mahlia, TMI & Kusumo, F 2017, 'Optimization of extraction of lipid from Isochrysis galbana microalgae species for biodiesel synthesis', Energy Sources, Part A: Recovery, Utilization and Environmental Effects, vol. 39, no. 11, pp. 1167-1175.View/Download from: Publisher's site
© 2017 Taylor & Francis Group, LLC. Microalgae are promising alternative plant sources for biodiesel production because of the signiﬁcant increase in lipid yield through heterotrophic cultivation and genetic engineering approaches. This study aims to evaluate the extraction and conversion of lipids from Isochrysis galbana. Response surface methodology (RSM) was used to optimize lipid extraction and thereby obtain high yields from the four microalgae species. The optimal lipid yields for Isochrysis galbana is 8.41 wt%. Moreover, the dominant lipid composition found from Isochrysis galbana extractions was palmitic acid (C16:0) at 22.3%. The high saturated acid of Isochrysis galbana contributed to the improved biodiesel properties because biodiesel quality is influenced by the lipid composition of microalgae species. The study employed the two-step esteriﬁcation–transesteriﬁcation process to convert the microalgae oil into biodiesel, glycerol, and water. The FAME content is 99.7% under the methanol to oil molar mass of 12:1, 1 wt%, 65°C, and 800 rpm. Furthermore, the main biodiesel properties, such as viscosity, higher heating value, and iodine value, were measured according to ASTM D6751 and EN 14124. Results show that microalgae oil can potentially be used as biofuel in future applications.
Tan, ES, Anwar, M, Kumaran, P, Indra, TM & Yoshikawa, K 2017, 'Air assist atomization characterization of palm biodiesel through experimental investigation and CFD simulation', Biofuels, vol. 8, no. 5, pp. 571-577.View/Download from: Publisher's site
© 2016 Informa UK Limited, trading as Taylor & Francis Group. The depletion of fossil fuel and environmental concerns have elevated biodiesel to emerge as a suitable alternative fuel to substitute diesel fuel. The study of spray formation is essential to improve the combustion systems of internal combustion engines and gas turbines. This paper aims to study the atomization characteristics of biodiesel derived from palm biodiesel through experimental test and simulation. The chemical fuel properties of biodiesel such as viscosity and density, will adversely affect the spray characteristics such as spray pattern, spray length, spray angle and Sauter Mean Diameter. The biodiesel fuels are blended with diesel in various ratios before being tested in an atomization test rig. Modelling of the atomizer are presented using computational fluid dynamics whereby comparisons are made with respect to the experimental results carried out in the atomizer test rig. There is no large discrepancy with the simulation results. The results showed that the higher content of biodiesel gives a larger droplet size and longer spray length. However, it produces smaller spray angle and spray width but with clearer vortex shape of spray pattern.
Tan, ES, Kumaran, P, Indra, TM & Yoshikawa, K 2017, 'Effect of Non-Edible Biodiesel Physical and Chemical Properties as Microturbine Fuel', Energy Procedia, vol. 142, pp. 413-418.View/Download from: Publisher's site
The world is facing critical energy concern, in view of depleting fossil fuel reserves and increasing environment pollution. Biodiesel can potentially substitute fossil fuel, and is produced through the transesterification of vegetable oils. This paper will emphasize on the transition from first generation derived from waste cooking oil, to second generation biodiesel derived from calophyllum inophyllum, which is a non-edible plant. The objective of this paper is to optimize the performance of biodiesel blends with diesel in a 30 kW microturbine. The characterization of chemical fuel properties of distillate and biodiesel blends will be conducted to determine if it meets international standards for power generation. Temperature profiles, pressure, and flame imaging will be closely monitored to detect possible problems in operability of the combustor caused by the differences in fuel characteristics. The findings may provide useful information towards optimization of microturbine performance, considering the wide range of biodiesel feedstock that exist. The paper outcome will show the potential of non-edible biodiesel blends to be used as alternative fuel in microturbines for power generation.
Aditiya, HB, Chong, WT, Mahlia, TMI, Sebayang, AH, Berawi, MA & Nur, H 2016, 'Second generation bioethanol potential from selected Malaysia's biodiversity biomasses: A review', WASTE MANAGEMENT, vol. 47, pp. 46-61.View/Download from: Publisher's site
Aditiya, HB, Mahlia, TMI, Chong, WT, Nur, H & Sebayang, AH 2016, 'Second generation bioethanol production: A critical review', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 66, pp. 631-653.View/Download from: Publisher's site
Dharma, S, Masjuki, HH, Ong, HC, Sebayang, AH, Silitonga, AS, Kusumo, F & Mahlia, TMI 2016, 'Optimization of biodiesel production process for mixed Jatropha curcas-Ceiba pentandra biodiesel using response surface methodology', ENERGY CONVERSION AND MANAGEMENT, vol. 115, pp. 178-190.View/Download from: Publisher's site
Fauzi, H, Metselaar, HSC, Mahlia, TMI, Ong, HC, Nasruddin & Khanlou, HM 2016, 'Preparation and thermal characteristics of eutectic fatty acids/Shorea javanica composite for thermal energy storage', APPLIED THERMAL ENGINEERING, vol. 100, pp. 62-67.View/Download from: Publisher's site
Hanif, M, Mahlia, TMI, Aditiya, HB, Chong, WT & Nasruddin 2016, 'Techno-economic and environmental assessment of bioethanol production from high starch and root yield Sri Kanji 1 cassava in Malaysia', ENERGY REPORTS, vol. 2, pp. 246-253.View/Download from: Publisher's site
Nasruddin, Alhamid, MI, Daud, Y, Surachman, A, Sugiyono, A, Aditya, HB & Mahlia, TMI 2016, 'Potential of geothermal energy for electricity generation in Indonesia: A review', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 53, pp. 733-740.View/Download from: Publisher's site
Sebayang, AH, Masjuki, HH, Ong, HC, Dharma, S, Silitonga, AS, Mahlia, TMI & Aditiya, HB 2016, 'A perspective on bioethanol production from biomass as alternative fuel for spark ignition engine', RSC ADVANCES, vol. 6, no. 18, pp. 14964-14992.View/Download from: Publisher's site
Sebayang, AH, Masjuki, HH, Ong, HC, Dharma, S, Silitonga, AS, Mahlia, TMI & Aditiya, HB 2016, 'ChemInform Abstract: A Perspective on Bioethanol Production from Biomass as Alternative Fuel for Spark Ignition Engine', ChemInform, vol. 47, no. 13, pp. no-no.View/Download from: Publisher's site
Sharma, RK, Ganesan, P, Tyagi, VV & Mahlia, TMI 2016, 'Accelerated thermal cycle and chemical stability testing of polyethylene glycol (PEG) 6000 for solar thermal energy storage', SOLAR ENERGY MATERIALS AND SOLAR CELLS, vol. 147, pp. 235-239.View/Download from: Publisher's site
Sharma, RK, Ganesan, P, Tyagi, VV, Mahlia, TMI & Mehrali, M 2016, 'Accelerated thermal cycle and chemical stability testing of Polyethylene glycol (PEG) 6000 for solar thermal energy storage (vol 147, pg 235, 2016)', SOLAR ENERGY MATERIALS AND SOLAR CELLS, vol. 151, pp. 191-191.View/Download from: Publisher's site
Silitonga, AS, Masjuki, HH, Ong, HC, Kusumo, F, Mahlia, TMI & Bahar, AH 2016, 'Pilot-scale production and the physicochemical properties of palm and Calophyllum inophyllum biodiesels and their blends', JOURNAL OF CLEANER PRODUCTION, vol. 126, pp. 654-666.View/Download from: Publisher's site
Silitonga, AS, Masjuki, HH, Ong, HC, Yusaf, T, Kusumo, F & Mahlia, TMI 2016, 'Synthesis and optimization of Hevea brasiliensis and Ricinus communis as feedstock for biodiesel production: A comparative study', INDUSTRIAL CROPS AND PRODUCTS, vol. 85, pp. 274-286.View/Download from: Publisher's site
Zi, SC, Chandren, S, Yuan, LS, Razali, R, Ho, CS, Hartanto, D, Mahlia, TMI & Nur, H 2016, 'New method to synthesize mesoporous titania by photodegradation of surfactant template', SOLID STATE SCIENCES, vol. 52, pp. 83-91.View/Download from: Publisher's site
Aditiya, HB, Sing, KP, Hanif, M & Mahlia, TMI 2015, 'Effect of acid pretreatment on enzymatic hydrolysis in bioethanol production from rice straw', International Journal of Technology, vol. 6, no. 1, pp. 3-10.View/Download from: Publisher's site
© IJTech 2015. Clean, safe and sustainable energy sources must be found to minimize all side-effects of fossil fuel consumption. Second generation bioethanol possesses a great potential as an alternative energy source especially in the transportation sector. In this study, rice straw was selected to be studied as a conversion of potential lignocellulosic biomass into bioethanol. Firstly, rice straw was processed with mechanical pretreatment using a home blender, followed by acid pretreatment using 2.0 M sulphuric acid (H2SO4) at 90°C for 60 minutes. The glucose yield was found to be 9.71 g/L. Then, rice straw pretreated with acid was hydrolyzed using 24 mg of cellulase from Tichoderma Ressei ATCC 26921 over a 72-hour duration, which yielded a total glucose count of 11.466 g/L. After fermentation with Saccharomyces cerevisiae, it was found that by combining enzymatic hydrolysis with acid pretreatment yielded a higher ethanol content after fermentation (0.1503% or 52.75% of theoretical value) compared to acidic pretreatment alone (0.013% or 11.26% of theoretical value).
Akhiani, AR, Mehrali, M, Latibari, ST, Mehrali, M, Mahlia, TMI, Sadeghinezhad, E & Metselaar, HSC 2015, 'One-Step Preparation of Form-Stable Phase Change Material through Self-Assembly of Fatty Acid and Graphene', JOURNAL OF PHYSICAL CHEMISTRY C, vol. 119, no. 40, pp. 22787-22796.View/Download from: Publisher's site
Fauzi, H, Metselaar, HSC, Mahlia, TMI, Silakhori, M & Ong, HC 2015, 'Thermal characteristic reliability of fatty acid binary mixtures as phase change materials (PCMs) for thermal energy storage applications', APPLIED THERMAL ENGINEERING, vol. 80, pp. 127-131.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M, Mahlia, TMI, Muttaqi, KM & Moghavvemi, S 2015, 'Effective utilization of excess energy in standalone hybrid renewable energy systems for improving comfort ability and reducing cost of energy: A review and analysis', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 42, pp. 726-734.View/Download from: Publisher's site
Latibari, ST, Mehrali, M, Mehrali, M, Afifi, ABM, Mahlia, TMI, Akhiani, AR & Metselaar, HSC 2015, 'Facile synthesis and thermal performances of stearic acid/titania core/shell nanocapsules by sol-gel method', ENERGY, vol. 85, pp. 635-644.View/Download from: Publisher's site
Latibari, ST, Mehrali, M, Mehrali, M, Mahlia, TMI & Metselaar, HSC 2015, 'Fabrication and Performances of Microencapsulated Palmitic Acid with Enhanced Thermal Properties', ENERGY & FUELS, vol. 29, no. 2, pp. 1010-1018.View/Download from: Publisher's site
Nurhadi, M, Efendi, J, Lee, SL, Mahlia, TMI, Chandren, S, Ho, CS & Nur, H 2015, 'Utilization of low rank coal as oxidation catalyst by controllable removal of its carbonaceous component', Journal of the Taiwan Institute of Chemical Engineers, vol. 46, pp. 183-190.View/Download from: Publisher's site
Silakhori, M, Fauzi, H, Mahmoudian, MR, Metselaar, HSC, Mahlia, TMI & Khanlou, HM 2015, 'Preparation and thermal properties of form-stable phase change materials composed of palmitic acid/polypyrrole/graphene nanoplatelets', ENERGY AND BUILDINGS, vol. 99, pp. 189-195.View/Download from: Publisher's site
Silitonga, AS, Masjuki, HH, Mahlia, TMI, Ong, HC, Kusumo, F, Aditiya, HB & Ghazali, NNN 2015, 'Schleichera oleosa L oil as feedstock for biodiesel production', FUEL, vol. 156, pp. 63-70.View/Download from: Publisher's site
Fauzi, H, Metselaar, HSC, Mahlia, TMI & Silakhori, M 2014, 'Sodium laurate enhancements the thermal properties and thermal conductivity of eutectic fatty acid as phase change material (PCM)', SOLAR ENERGY, vol. 102, pp. 333-337.View/Download from: Publisher's site
Fauzi, H, Metselaar, HSC, Mahlia, TMI & Silakhori, M 2014, 'Thermo-physical stability of fatty acid eutectic mixtures subjected to accelerated aging for thermal energy storage (TES) application', APPLIED THERMAL ENGINEERING, vol. 66, no. 1-2, pp. 328-334.View/Download from: Publisher's site
Ganandran, GSB, Mahlia, TMI, Ong, HC, Rismanchi, B & Chong, WT 2014, 'Cost-Benefit Analysis and Emission Reduction of Energy Efficient Lighting at the Universiti Tenaga Nasional', SCIENTIFIC WORLD JOURNAL.View/Download from: Publisher's site
Hamdani, Thaib, R, Irwansyah, Dailami & Mahlia, TMI 2014, 'Experimental investigation on melting heat transfer of paraffin wax-Al2O3 storage system', International Journal of Applied Engineering Research, vol. 9, no. 22, pp. 17903-17910.
© Research India Publications. Background: A systems ofLatent Heat Thermal Energy Storage (LHTES) based on paraffin wax (n-octadecane/C18 H18) have low heat transfer rates during either melting or freezing processes. To enhance paraffin wax thermal conductivity, alumina (Al2O3) as a material which high conductivity was employed. Parafin wax was dispersed with alumina homogenously with volume fraction 2%, 4%, 6%, 8% and 10%.Objective: This paper examines the thermal conductivity enhancement using paraffin wax as a heat storage material by mixed with alumina (Al2O3) particles.Results:At starting heat, paraffin wax absorbs sensible heat and then latent heat which takes place at a temperature nearly constant. Similarly, at the beginning of the heating process, temperature increases rapidly until paraffin reach its melting temperature and tend to increased constantly after the temperature reached 60°C. Conclusion: The addition of Al2O3 particles which have a high thermal conductivity could able to increase thermal conductivity of paraffin wax as a heat storage media. Adding amount of Al2O3 particles will reduce latent heat thermal of energy storage material. The conduction heat transfers dominantly during melting and freezing processes. Alumina particles is play significantly in the solidification process comparing to melting process. During freezing process, solid layer was formed on top surface of heat exchanger and remain stable. It can be concluded that by adding alumina particles could increase heat exctraction during solidification process. As a results, it produces low latent heat and high thermal conductivity.
Hanif, M, Mahlia, TMI, Zare, A, Saksandan, TJ & Metselaar, HSC 2014, 'Potential energy savings by radiative cooling system for a building in tropical climate', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 32, pp. 642-650.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M & Mahlia, TMI 2014, 'Genetic algorithm based optimization on modeling and design of hybrid renewable energy systems', ENERGY CONVERSION AND MANAGEMENT, vol. 85, pp. 120-130.View/Download from: Publisher's site
Latibari, ST, Mehrali, M, Mehrali, M, Mahlia, TMI & Metselaar, HSC 2014, 'Facile Preparation of Carbon Microcapsules Containing Phase-Change Material with Enhanced Thermal Properties', SCIENTIFIC WORLD JOURNAL.View/Download from: Publisher's site
Mahlia, TMI, Saktisandan, TJ, Jannifar, A, Hasan, MH & Matseelar, HSC 2014, 'A review of available methods and development on energy storage; technology update', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 33, pp. 532-545.View/Download from: Publisher's site
Mahlia, TMI, Wong, KV, Honnery, D & Hasan, MH 2014, 'Sensitivity analysis of potential fuel savings by implementation of fuel economy standards for motorcycle', CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY, vol. 16, no. 1, pp. 175-182.View/Download from: Publisher's site
Mehrali, M, Latibari, ST, Mehrali, M, Mahlia, TMI & Metselaar, HSC 2014, 'Effect of carbon nanospheres on shape stabilization and thermal behavior of phase change materials for thermal energy storage', ENERGY CONVERSION AND MANAGEMENT, vol. 88, pp. 206-213.View/Download from: Publisher's site
Mehrali, M, Latibari, ST, Mehrali, M, Mahlia, TMI, Sadeghinezhad, E & Metselaar, HSC 2014, 'Preparation of nitrogen-doped graphene/palmitic acid shape stabilized composite phase change material with remarkable thermal properties for thermal energy storage', APPLIED ENERGY, vol. 135, pp. 339-349.View/Download from: Publisher's site
Mohammadnejad, M, Ghazvini, M & Mahlia, TMI 2014, 'Fuel economy standards for light duty vehicles and their potential to aid Iran toward achieving fuel saving and emissions reduction', CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY, vol. 16, no. 3, pp. 661-666.View/Download from: Publisher's site
Ong, HC, Masjuki, HH, Mahlia, TMI, Silitonga, AS, Chong, WT & Leong, KY 2014, 'Optimization of biodiesel production and engine performance from high free fatty acid Calophyllum inophyllum oil in CI diesel engine', ENERGY CONVERSION AND MANAGEMENT, vol. 81, pp. 30-40.View/Download from: Publisher's site
Ong, HC, Masjuki, HH, Mahlia, TMI, Silitonga, AS, Chong, WT & Yusaf, T 2014, 'Engine performance and emissions using Jatropha curcas, Ceiba pentandra and Calophyllum inophyllum biodiesel in a CI diesel engine', ENERGY, vol. 69, pp. 427-445.View/Download from: Publisher's site
Shafie, SM, Masjuki, HH & Mahlia, TMI 2014, 'Rice straw supply chain for electricity generation in Malaysia: Economical and environmental assessment', APPLIED ENERGY, vol. 135, pp. 299-308.View/Download from: Publisher's site
Sharma, RK, Ganesan, P, Sahu, JN, Metselaar, HSC & Mahlia, TMI 2014, 'Numerical study for enhancement of solidification of phase change materials using trapezoidal cavity', POWDER TECHNOLOGY, vol. 268, pp. 38-47.View/Download from: Publisher's site
Silakhori, M, Metselaar, HSC, Mahlia, TMI & Fauzi, H 2014, 'Preparation and characterisation of microencapsulated paraffin wax with polyaniline-based polymer shells for thermal energy storage', MATERIALS RESEARCH INNOVATIONS, vol. 18, pp. 480-484.View/Download from: Publisher's site
Silakhori, M, Metselaar, HSC, Mahlia, TMI, Fauzi, H, Baradaran, S & Naghavi, MS 2014, 'Palmitic acid/polypyrrole composites as form-stable phase change materials for thermal energy storage', ENERGY CONVERSION AND MANAGEMENT, vol. 80, pp. 491-497.View/Download from: Publisher's site
Anisur, MR, Mahfuz, MH, Kibria, MA, Saidur, R, Metselaar, IHSC & Mahlia, TMI 2013, 'Curbing global warming with phase change materials for energy storage', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 18, pp. 23-30.View/Download from: Publisher's site
Atabani, AE, Badruddin, IA, Mahlia, TMI, Masjuki, HH, Mofijur, M, Lee, KT & Chong, WT 2013, 'Fuel Properties of Croton megalocarpus, Calophyllum inophyllum, and Cocos nucifera (coconut) Methyl Esters and their Performance in a Multicylinder Diesel Engine', ENERGY TECHNOLOGY, vol. 1, no. 11, pp. 685-694.View/Download from: Publisher's site
Atabani, AE, Badruddin, IA, Masjuki, HH, Chong, WT, Mahlia, TMI & Lee, KT 2013, 'Investigation of physical and chemical properties of potential edible and non-edible feedstocks for biodiesel production, a comparative analysis', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 21, pp. 749-755.View/Download from: Publisher's site
Atabani, AE, Mahlia, TMI, Masjuki, HH, Badruddin, IA, Yussof, HW, Chong, WT & Lee, KT 2013, 'A comparative evaluation of physical and chemical properties of biodiesel synthesized from edible and non-edible oils and study on the effect of biodiesel blending', ENERGY, vol. 58, pp. 296-304.View/Download from: Publisher's site
Atabani, AE, Silitonga, AS, Ong, HC, Mahlia, TMI, Masjuki, HH, Badruddin, IA & Fayaz, H 2013, 'Non-edible vegetable oils: A critical evaluation of oil extraction, fatty acid compositions, biodiesel production, characteristics, engine performance and emissions production', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 18, pp. 211-245.View/Download from: Publisher's site
Fauzi, H, Metselaar, HSC, Mahlia, TMI, Silakhori, M & Nur, H 2013, 'Phase change material: Optimizing the thermal properties and thermal conductivity of myristic acid/palmitic acid eutectic mixture with acid-based surfactants', APPLIED THERMAL ENGINEERING, vol. 60, no. 1-2, pp. 261-265.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M & Mahlia, TMI 2013, 'Analysis and evaluation of various aspects of solar radiation in the Palestinian territories', ENERGY CONVERSION AND MANAGEMENT, vol. 73, pp. 57-68.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M & Mahlia, TMI 2013, 'Characterization of PV panel and global optimization of its model parameters using genetic algorithm', ENERGY CONVERSION AND MANAGEMENT, vol. 73, pp. 10-25.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M & Mahlia, TMI 2013, 'Current utilization of microturbines as a part of a hybrid system in distributed generation technology', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 21, pp. 142-152.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M & Mahlia, TMI 2013, 'Design of an optimized photovoltaic and microturbine hybrid power system for a remote small community: Case study of Palestine', ENERGY CONVERSION AND MANAGEMENT, vol. 75, pp. 271-281.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M & Mahlia, TMI 2013, 'Energy trends in Palestinian territories of West Bank and Gaza Strip: Possibilities for reducing the reliance on external energy sources', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 28, pp. 117-129.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M & Mahlia, TMI 2013, 'Techno-economic analysis of an optimized photovoltaic and diesel generator hybrid power system for remote houses in a tropical climate', ENERGY CONVERSION AND MANAGEMENT, vol. 69, pp. 163-173.View/Download from: Publisher's site
Latibari, ST, Mehrali, M, Mehrali, M, Mahlia, TMI & Metselaar, HSC 2013, 'Synthesis, characterization and thermal properties of nanoencapsulated phase change materials via sol-gel method', ENERGY, vol. 61, pp. 664-672.View/Download from: Publisher's site
Mahlia, TMI, Tohno, S & Tezuka, T 2013, 'International experience on incentive program in support of fuel economy standards and labelling for motor vehicle: A comprehensive review', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 25, pp. 18-33.View/Download from: Publisher's site
Mehrali, M, Latibari, ST, Mehrali, M, Mahlia, TMI & Metselaar, HSC 2013, 'Preparation and properties of highly conductive palmitic acid/graphene oxide composites as thermal energy storage materials', ENERGY, vol. 58, pp. 628-634.View/Download from: Publisher's site
Mehrali, M, Latibari, ST, Mehrali, M, Mahlia, TMI, Metselaar, HSC, Naghavi, MS, Sadeghinezhad, E & Akhiani, AR 2013, 'Preparation and characterization of palmitic acid/graphene nanoplatelets composite with remarkable thermal conductivity as a novel shape-stabilized phase change material', APPLIED THERMAL ENGINEERING, vol. 61, no. 2, pp. 633-640.View/Download from: Publisher's site
Ong, HC, Silitonga, AS, Masjuki, HH, Mahlia, TMI, Chong, WT & Boosroh, MH 2013, 'Production and comparative fuel properties of biodiesel from non-edible oils: Jatropha curcas, Sterculia foetida and Ceiba pentandra', ENERGY CONVERSION AND MANAGEMENT, vol. 73, pp. 245-255.View/Download from: Publisher's site
Ran, NHM, Yuliati, L, Lee, SL, Mahlia, TMI & Nur, H 2013, 'Liquid-gas boundary catalysis by using gold/polystyrene-coated hollow titania', JOURNAL OF COLLOID AND INTERFACE SCIENCE, vol. 394, pp. 490-497.View/Download from: Publisher's site
Rismanchi, B, Saidur, R, Masjuki, HH & Mahlia, TMI 2013, 'Modeling and simulation to determine the potential energy savings by implementing cold thermal energy storage system in office buildings', ENERGY CONVERSION AND MANAGEMENT, vol. 75, pp. 152-161.View/Download from: Publisher's site
Shekarchian, M, Zarifi, F, Moghavvemi, M, Motasemi, F & Mahlia, TMI 2013, 'Energy, exergy, environmental and economic analysis of industrial fired heaters based on heat recovery and preheating techniques', ENERGY CONVERSION AND MANAGEMENT, vol. 71, pp. 51-61.View/Download from: Publisher's site
Silakhori, M, Naghavi, MS, Metselaar, HSC, Mahlia, TMI, Fauzi, H & Mehrali, M 2013, 'Accelerated Thermal Cycling Test of Microencapsulated Paraffin Wax/Polyaniline Made by Simple Preparation Method for Solar Thermal Energy Storage', MATERIALS, vol. 6, no. 5, pp. 1608-1620.View/Download from: Publisher's site
Silitonga, AS, Masjuki, HH, Mahlia, TMI, Ong, HC & Chong, WT 2013, 'Experimental study on performance and exhaust emissions of a diesel engine fuelled with Ceiba pentandra biodiesel blends', ENERGY CONVERSION AND MANAGEMENT, vol. 76, pp. 828-836.View/Download from: Publisher's site
Silitonga, AS, Masjuki, HH, Mahlia, TMI, Ong, HC, Atabani, AE & Chong, WT 2013, 'A global comparative review of biodiesel production from jatropha curcas using different homogeneous acid and alkaline catalysts: Study of physical and chemical properties', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 24, pp. 514-533.View/Download from: Publisher's site
Silitonga, AS, Masjuki, HH, Mahlia, TMI, Ong, HC, Chong, WT & Boosroh, MH 2013, 'Overview properties of biodiesel diesel blends from edible and non-edible feedstock', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 22, pp. 346-360.View/Download from: Publisher's site
Silitonga, AS, Ong, HC, Mahlia, TMI, Masjuki, HH & Chong, WT 2013, 'Characterization and production of Ceiba pentandra biodiesel and its blends', FUEL, vol. 108, pp. 855-858.View/Download from: Publisher's site
Silitonga, AS, Ong, HC, Masjuki, HH, Mahlia, TMI, Chong, WT & Yusaf, TF 2013, 'Production of biodiesel from Sterculia foetida and its process optimization', FUEL, vol. 111, pp. 478-484.View/Download from: Publisher's site
Zarifi, F, Mahlia, TMI, Motasemi, F, Shekarchian, M & Moghavvemi, M 2013, 'Current and future energy and exergy efficiencies in the Iran's transportation sector', ENERGY CONVERSION AND MANAGEMENT, vol. 74, pp. 24-34.View/Download from: Publisher's site
Adnan, R, Masjuki, HH & Mahlia, TMI 2012, 'Performance and emission analysis of hydrogen fueled compression ignition engine with variable water injection timing', ENERGY, vol. 43, no. 1, pp. 416-426.View/Download from: Publisher's site
Atabani, AE, Silitonga, AS & Mahlia, TMI 2012, 'Cost benefit analysis and environmental impact of fuel economy standards for passenger cars in Indonesia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 5, pp. 3547-3558.View/Download from: Publisher's site
Atabani, AE, Silitonga, AS, Badruddin, IA, Mahlia, TMI, Masjuki, HH & Mekhilef, S 2012, 'A comprehensive review on biodiesel as an alternative energy resource and its characteristics', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 4, pp. 2070-2093.View/Download from: Publisher's site
Hai, S 2012, 'Reduction Measure for 3-D structure During Near-Source Ground Motions', Energy Procedia, vol. 14, pp. 1613-1617.View/Download from: Publisher's site
Hasan, MH, Mahlia, TMI & Nur, H 2012, 'A review on energy scenario and sustainable energy in Indonesia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 4, pp. 2316-2328.View/Download from: Publisher's site
Hasan, MH, Muzammil, WK, Mahlia, TMI, Jannifar, A & Hasanuddin, I 2012, 'A review on the pattern of electricity generation and emission in Indonesia from 1987 to 2009', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 5, pp. 3206-3219.View/Download from: Publisher's site
Leong, KY, Saidur, R, Mahlia, TMI & Yau, YH 2012, 'Entropy generation analysis of nanofluid flow in a circular tube subjected to constant wall temperature', INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER, vol. 39, no. 8, pp. 1169-1175.View/Download from: Publisher's site
Leong, KY, Saidur, R, Mahlia, TMI & Yau, YH 2012, 'Modeling of shell and tube heat recovery exchanger operated with nanofluid based coolants', INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, vol. 55, no. 4, pp. 808-816.View/Download from: Publisher's site
Leong, KY, Saidur, R, Mahlia, TMI & Yau, YH 2012, 'Performance investigation of nanofluids as working fluid in a thermosyphon air preheater', INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER, vol. 39, no. 4, pp. 523-529.View/Download from: Publisher's site
Leong, KY, Saidur, R, Mahlia, TMI & Yau, YH 2012, 'Predicting size reduction of shell and tube heat recovery exchanger operated with nanofluids based coolants and its associated energy saving', ENERGY EDUCATION SCIENCE AND TECHNOLOGY PART A-ENERGY SCIENCE AND RESEARCH, vol. 30, no. 1, pp. 1-14.
Mahlia, TMI, Cheng, LW, Salikka, LCS, Lim, CL, Hasan, MH & Hamdani, U 2012, 'Drying garcinia atroviridis using waste heat from condenser of a split room air conditioner', International Journal of Mechanical and Materials Engineering, vol. 7, no. 2, pp. 171-176.
Garcinia Atroviridis which grows wildly in peninsular Malaysia are popular fruits in Southeast Asia and Northern states due to its economical and medical value. To preserve and increase economic value of the fruit, it usually dried or freeze. The paper discusses the experiment study of drying Garcinia Atroviridis using waste heat from condenser of a typical split air conditioner as a dryer. Test was conducted in a drying chamber housing the condensing unit, where the heat rejected by the condenser was used for drying the Garcinia Atroviridis. The experimental setup has been developed as an integrated air conditioner for drying purpose using waste heat from condenser. The study found that using waste heat from room air conditioner condenser for drying purpose is very reliable during raining day and efficient without additional electricity cost.
Mahlia, TMI, Ng, HM, Olofsson, T, Andriayana, A & Hasanuddin, I 2012, 'Energy and cost savings of optimal thickness for selected insulation materials and air gaps for building walls in tropical climate', ENERGY EDUCATION SCIENCE AND TECHNOLOGY PART A-ENERGY SCIENCE AND RESEARCH, vol. 29, no. 1, pp. 649-662.
Mahlia, TMI, Tohno, S & Tezuka, T 2012, 'A global review of success story on implementation of fuel economy standard for passenger cars: Lesson for other countries', ENERGY EDUCATION SCIENCE AND TECHNOLOGY PART A-ENERGY SCIENCE AND RESEARCH, vol. 29, no. 2, pp. 947-972.
Mahlia, TMI, Tohno, S & Tezuka, T 2012, 'A review on fuel economy test procedure for automobiles: Implementation possibilities in Malaysia and lessons for other countries', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 6, pp. 4029-4046.View/Download from: Publisher's site
Mahlia, TMI, Tohno, S & Tezuka, T 2012, 'History and current status of the motor vehicle energy labeling and its implementation possibilities in Malaysia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 4, pp. 1828-1844.View/Download from: Publisher's site
Mahlia, TMI, Yong, JH, Safari, A & Mekhilef, S 2012, 'Techno-economic analysis of palm oil mill wastes to generate power for grid-connected utilization', ENERGY EDUCATION SCIENCE AND TECHNOLOGY PART A-ENERGY SCIENCE AND RESEARCH, vol. 28, no. 2, pp. 1111-1130.
Nur, H, Kee, GL, Hamdan, H, Mahlia, TMI, Efendi, J & Metselaar, HSC 2012, 'Organosulfonic acid functionalized zeolite ZSM-5 as temperature tolerant proton conducting material', INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, vol. 37, no. 17, pp. 12513-12521.View/Download from: Publisher's site
Olofsson, T & Mahlia, TMI 2012, 'Modeling and simulation of the energy use in an occupied residential building in cold climate', APPLIED ENERGY, vol. 91, no. 1, pp. 432-438.View/Download from: Publisher's site
Ong, HC, Mahlia, TMI & Masjuki, HH 2012, 'A review on energy pattern and policy for transportation sector in Malaysia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 1, pp. 532-542.View/Download from: Publisher's site
Rismanchi, B, Saidur, R, Masjuki, HH & Mahlia, TMI 2012, 'Energetic, economic and environmental benefits of utilizing the ice thermal storage systems for office building applications', ENERGY AND BUILDINGS, vol. 50, pp. 347-354.View/Download from: Publisher's site
Rismanchi, B, Saidur, R, Masjuki, HH & Mahlia, TMI 2012, 'Thermodynamic evaluation of utilizing different ice thermal energy storage systems for cooling application in office buildings in Malaysia', ENERGY AND BUILDINGS, vol. 53, pp. 117-126.View/Download from: Publisher's site
Shafie, SM, Mahlia, TMI, Masjuki, HH & Ahmad-Yazid, A 2012, 'A review on electricity generation based on biomass residue in Malaysia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 8, pp. 5879-5889.View/Download from: Publisher's site
Shekarchian, M, Moghavvemi, M, Motasemi, F, Zarifi, F & Mahlia, TMI 2012, 'Energy and fuel consumption forecast by retrofitting absorption cooling in Malaysia from 2012 to 2025', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 8, pp. 6128-6141.View/Download from: Publisher's site
Shekarchian, M, Moghavvemi, M, Rismanchi, B, Mahlia, TMI & Olofsson, T 2012, 'The cost benefit analysis and potential emission reduction evaluation of applying wall insulation for buildings in Malaysia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 7, pp. 4708-4718.View/Download from: Publisher's site
Silitonga, AS, Atabani, AE & Mahlia, TMI 2012, 'Review on fuel economy standard and label for vehicle in selected ASEAN countries', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 16, no. 3, pp. 1683-1695.View/Download from: Publisher's site
Adnan, R, Masjuki, HH & Mahlia, TMI 2011, 'Mathematical modeling on the effect of equivalence ratio in emission characteristics of compression ignition engine with hydrogen substitution', APPLIED MATHEMATICS AND COMPUTATION, vol. 217, no. 13, pp. 6144-6158.View/Download from: Publisher's site
Chong, WT, Naghavi, MS, Poh, SC, Mahlia, TMI & Pan, KC 2011, 'Techno-economic analysis of a wind-solar hybrid renewable energy system with rainwater collection feature for urban high-rise application', APPLIED ENERGY, vol. 88, no. 11, pp. 4067-4077.View/Download from: Publisher's site
Husnawan, M, Masjuki, HH & Mahlia, TMI 2011, 'The interest of combining two additives with palm olein as selected lubricant components', INDUSTRIAL LUBRICATION AND TRIBOLOGY, vol. 63, no. 2-3, pp. 203-209.View/Download from: Publisher's site
Jayed, MH, Masjuki, HH, Kalam, MA, Mahlia, TMI, Husnawan, M & Liaquat, AM 2011, 'Prospects of dedicated biodiesel engine vehicles in Malaysia and Indonesia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 1, pp. 220-235.View/Download from: Publisher's site
Mahlia, TMI & Chan, PL 2011, 'Life cycle cost analysis of fuel cell based cogeneration system for residential application in Malaysia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 1, pp. 416-426.View/Download from: Publisher's site
Mahlia, TMI, Razak, HA & Nursahida, MA 2011, 'Life cycle cost analysis and payback period of lighting retrofit at the University of Malaya', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 2, pp. 1125-1132.View/Download from: Publisher's site
Mahlia, TMI, Saidur, R, Yanti, PAA & Masjuki, HH 2011, 'Role of energy guide labels in consumers purchase decision for household electrical appliances', ENERGY EDUCATION SCIENCE AND TECHNOLOGY PART A-ENERGY SCIENCE AND RESEARCH, vol. 27, no. 1, pp. 95-104.
Mahlia, TMI, Taufiq, BN, Ong, KP & Saidur, R 2011, 'Exergy analysis for day lighting, electric lighting and space cooling systems for a room space in a tropical climate', ENERGY AND BUILDINGS, vol. 43, no. 7, pp. 1676-1684.View/Download from: Publisher's site
Mazandarani, A, Mahlia, TMI, Chong, WT & Moghavvemi, M 2011, 'Fuel consumption and emission prediction by Iranian power plants until 2025', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 3, pp. 1575-1592.View/Download from: Publisher's site
Mohammadnejad, M, Ghazvini, M, Mahlia, TMI & Andriyana, A 2011, 'A review on energy scenario and sustainable energy in Iran', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 9, pp. 4652-4658.View/Download from: Publisher's site
Ong, HC, Mahlia, TMI & Masjuki, HH 2011, 'A review on emissions and mitigation strategies for road transport in Malaysia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 8, pp. 3516-3522.View/Download from: Publisher's site
Ong, HC, Mahlia, TMI & Masjuki, HH 2011, 'A review on energy scenario and sustainable energy in Malaysia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 1, pp. 639-647.View/Download from: Publisher's site
Ong, HC, Mahlia, TMI, Masjuki, HH & Norhasyima, RS 2011, 'Comparison of palm oil, Jatropha curcas and Calophyllum inophyllum for biodiesel: A review', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 8, pp. 3501-3515.View/Download from: Publisher's site
Saidur, R & Mahlia, TMI 2011, 'Impacts of energy efficiency standard on motor energy savings and emission reductions', CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY, vol. 13, no. 1, pp. 103-109.View/Download from: Publisher's site
Saidur, R, Hasanuzzaman, M, Mahlia, TMI, Rahim, NA & Mohammed, HA 2011, 'Chillers energy consumption, energy savings and emission analysis in an institutional buildings', ENERGY, vol. 36, no. 8, pp. 5233-5238.View/Download from: Publisher's site
Saidur, R, Mahlia, TMI & Hasanuzzaman, M 2011, 'Developing energy performance standard, label and test procedures and impacts analysis for commercial chillers', ENERGY EDUCATION SCIENCE AND TECHNOLOGY PART A-ENERGY SCIENCE AND RESEARCH, vol. 27, no. 1, pp. 175-190.
Shafie, SM, Mahlia, TMI, Masjuki, HH & Andriyana, A 2011, 'Current energy usage and sustainable energy in Malaysia: A review', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 9, pp. 4370-4377.View/Download from: Publisher's site
Shekarchian, M, Moghavvemi, M, Mahlia, TMI & Mazandarani, A 2011, 'A review on the pattern of electricity generation and emission in Malaysia from 1976 to 2008', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 6, pp. 2629-2642.View/Download from: Publisher's site
Shekarchian, M, Moghavvemi, M, Motasemi, F & Mahlia, TMI 2011, 'Energy savings and cost-benefit analysis of using compression and absorption chillers for air conditioners in Iran', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 4, pp. 1950-1960.View/Download from: Publisher's site
Silitonga, AS, Atabani, AE, Mahlia, TMI & Sebayang, AH 2011, 'Techno-economic analysis and environmental impact of fuel economy labels for passenger cars in Indonesia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 9, pp. 5212-5217.View/Download from: Publisher's site
Silitonga, AS, Atabani, AE, Mahlia, TMI, Masjuki, HH, Badruddin, IA & Mekhilef, S 2011, 'A review on prospect of Jatropha curcas for biodiesel in Indonesia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 15, no. 8, pp. 3733-3756.View/Download from: Publisher's site
Adnan, R, Masjuki, HH & Mahlia, TMI 2010, 'Computational simulation on emissions of hydrogen fueled compression ignition engine with variable combustion temperature', International Journal of Mechanical and Materials Engineering, vol. 5, no. 2, pp. 251-259.
In this paper, computational simulation on the effect of combustion temperature on emissions characteristics of hydrogen-fuelled compression ignition engine was performed. Combustion process was modeled based on Equilibrium Constant Method (ECM) and programmed using MATLAB program in order to calculate mole fractions of 18 combustion products when hydrogendiesel fuels blends is burnt at variable combustion temperatures. It is observed that throughout all equivalence ratios, higher temperature increases H2, CO, HCN, atoms C, O and H, NO, OH, NO2 and O3 emissions and decreases CO2, H2O, NH3 and CH4, N2, O2 and HNO3 emissions. The highest H 2O emission occurs during stoichiometric combustion and decrease in combustion temperature causes insignificant changes in atom N emission.
Adnan, R, Masjuki, HH & Mahlia, TMI 2010, 'Experimental investigation on in-cylinder pressure and emissions of diesel engine with port injection hydrogen system', International Journal of Mechanical and Materials Engineering, vol. 5, no. 2, pp. 136-141.
Towards the efforts of increasing the performance and reducing pollutant emissions of diesel engine, port injection gaseous fuel system is one of the solutions and it is applicable for dual fuel combustion engines. In this study, series of experiments were carried out to study the effect of continuous port injection hydrogen gas on in-cylinder pressure and emissions of unmodified single cylinder diesel engine. Injection of hydrogen results an increase in in-cylinder peak pressure in the range of 5 to 23 bars and exhaust gas temperature in the range of 3.1% to 10.2% throughout all engine speeds. There were also increases in NOx, CO and CO2 emissions due to presence of hydrogen ranges between 50 to 200 ppm, 420 to 760 ppm and 1.1% to 4.2% (by volume), respectively. On the other hand, continuous port injection hydrogen addition in diesel engine showed reduction of hydrocarbon (HC) at the average of 15 ppm and O2 emissions at the average of 6% (by volume).
Aizura, AB, Mahlia, TMI & Masjuki, HH 2010, 'Potential fuel savings and emissions reduction from fuel economy standards implementation for motor-vehicles', CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY, vol. 12, no. 3, pp. 255-263.View/Download from: Publisher's site
Aljibori, HSS, Chong, WP, Mahlia, TMI, Chong, WT, Edi, P, Al-qrimli, H, Anjum, I & Zahari, R 2010, 'Load-displacement behavior of glass fiber/epoxy composite plates with circular cut-outs subjected to compressive load', MATERIALS & DESIGN, vol. 31, no. 1, pp. 466-474.View/Download from: Publisher's site
Mahlia, TMI & Iqbal, A 2010, 'Cost benefits analysis and emission reductions of optimum thickness and air gaps for selected insulation materials for building walls in Maldives', ENERGY, vol. 35, no. 5, pp. 2242-2250.View/Download from: Publisher's site
Mahlia, TMI & Saidur, R 2010, 'A review on test procedure, energy efficiency standards and energy labels for room air conditioners and refrigerator-freezers', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 14, no. 7, pp. 1888-1900.View/Download from: Publisher's site
Mahlia, TMI & Yanti, PAA 2010, 'Cost efficiency analysis and emission reduction by implementation of energy efficiency standards for electric motors', JOURNAL OF CLEANER PRODUCTION, vol. 18, no. 4, pp. 365-374.View/Download from: Publisher's site
Mahlia, TMI, Hor, CG, Masjuki, HH, Husnawan, M, Varman, M & Mekhilef, S 2010, 'CLOTHES DRYING FROM ROOM AIR CONDITIONING WASTE HEAT: THERMODYNAMICS INVESTIGATION', ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING, vol. 35, no. 1B, pp. 339-351.
Mahlia, TMI, Hor, CG, Masjuki, HH, Husnawan, M, Varman, M & Mekhilef, S 2010, 'Clothes drying from room air conditioning waste heat: Thermodynamics investigation', Arabian Journal for Science and Engineering, vol. 35, no. 1, pp. 339-351.
This paper discusses an experimental study for using heat wasted from a split-type room air conditioner for clothes drying. The study compares the effectiveness of this drying system to a conventional one in terms of duration required to dry the clothes and energy consumption. The objectives of the study are to analyze performance of a room air-conditioner as clothes dryer and to evaluate the effectiveness of its heat waste for a drying system. The experiment is conducted for three drying conditions, namely, outdoor natural drying at midday, indoor natural drying, and drying using air-conditioner waste heat. The study found that using room air-conditioner waste heat for clothes drying is very reliable, especially in congested high-rise residential areas, without additional electricity cost. © 2008 by King Fahd University of Petroleum & Minerals (KFUPM).
Mahlia, TMI, Saidur, R, Husnawan, M, Masjuki, HH & Kalam, MA 2010, 'An approach to estimate the life-cycle cost of energy efficiency improvement of room air conditioners', ENERGY EDUCATION SCIENCE AND TECHNOLOGY PART A-ENERGY SCIENCE AND RESEARCH, vol. 26, no. 1, pp. 1-11.
Mahlia, TMI, Saidur, R, Memon, LA, Zulkifli, NWM & Masjuki, HH 2010, 'A review on fuel economy standard for motor vehicles with the implementation possibilities in Malaysia', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 14, no. 9, pp. 3092-3099.View/Download from: Publisher's site
Mazandarani, A, Mahlia, TMI, Chong, WT & Moghavvemi, M 2010, 'A review on the pattern of electricity generation and emission in Iran from 1967 to 2008', RENEWABLE & SUSTAINABLE ENERGY REVIEWS, vol. 14, no. 7, pp. 1814-1829.View/Download from: Publisher's site
Saidur, R & Mahlia, TMI 2010, 'Energy, economic and environmental benefits of using high-efficiency motors to replace standard motors for the Malaysian industries', ENERGY POLICY, vol. 38, no. 8, pp. 4617-4625.View/Download from: Publisher's site
Yusuf, K, Nukman, Y, Yusof, TM, Dawal, SZ, Yang, HQ, Mahlia, TMI & Tamrin, KF 2010, 'Effect of cutting parameters on the surface roughness of titanium alloys using end milling process', SCIENTIFIC RESEARCH AND ESSAYS, vol. 5, no. 11, pp. 1284-1293.
Hassan, MH, Kalam, MA, Mahlia, TMI, Aris, I, Nizam, MK, Abdullah, S & Ali, Y 2009, 'Experimental Test of a New Compressed Natural Gas Direct Injection Engine', ENERGY & FUELS, vol. 23, no. 10, pp. 4981-4987.View/Download from: Publisher's site
Husnawan, M, Masjuki, HH, Mahlia, TMI & Saifullah, MG 2009, 'Thermal analysis of cylinder head carbon deposits from single cylinder diesel engine fueled by palm oil-diesel fuel emulsions', APPLIED ENERGY, vol. 86, no. 10, pp. 2107-2113.View/Download from: Publisher's site
Husnawan, M, Masjuki, HH, Mahlia, TMI, Mekhilef, S & Saifullah, MG 2009, 'Use of post flame metal-based and oxygenated additive combination for biodiesel-diesel blends', JOURNAL OF SCIENTIFIC & INDUSTRIAL RESEARCH, vol. 68, no. 12, pp. 1049-1052.
Kalam, MA, Masjuki, HH, Redzuan, M, Mahlia, TMI, Fuad, MA, Mohibah, M, Halim, KH, Ishak, A, Khair, M, Shahrir, A & Yusoff, A 2009, 'Development and test of a new catalytic converter for natural gas fuelled engine', SADHANA-ACADEMY PROCEEDINGS IN ENGINEERING SCIENCES, vol. 34, no. 3, pp. 467-481.View/Download from: Publisher's site
Yanti, PAA & Mahlia, TM 2009, 'Market transformation due to implementation of energy efficiency standards and labels implementation for electric motor', Journal of Applied Sciences, vol. 9, no. 14, pp. 2630-2634.View/Download from: Publisher's site
This study attempts to investigate about the market transformation of electric motor due to implementation of minimum energy efficiency standards and energy labels. The study found that efficiency of electric motor will increase from 90.0 to 92.5% due to implementation of standards and will increase further to 93.5% due to energy labels, this study is only investigate electric motor, however the method is also applicable for predicting market transformation for other product without major modification. © 2009 Asian Network for Scientific Information.
Yanti, PAA & Mahlia, TMI 2009, 'Considerations for the selection of an applicable energy efficiency test procedure for electric motors in Malaysia: Lessons for other developing countries', ENERGY POLICY, vol. 37, no. 9, pp. 3467-3474.View/Download from: Publisher's site
Kalam, MA, Saifullah, MG, Masjuki, HH, Husnawan, M & Mahlia, TMI 2008, 'PAH and other emissions from coconut oil blended fuels', JOURNAL OF SCIENTIFIC & INDUSTRIAL RESEARCH, vol. 67, no. 11, pp. 1031-1035.
Mahlia, TMI 2008, 'η3e Efficiency (energy, economic and environmental) for performance analysis of an engineering system', International Journal of Mechanical and Materials Engineering, vol. 3, no. 1, pp. 105-107.
Environmental consciousness has changed the methods of analyzing of an engineering system. For long time an efficiency of an engineering system has been analyzed according to its energy and economic efficiency. This paper attempts to introduce an approach to evaluate the efficiency which call η3e (triple e efficiency). The η3e efficiency is a method of describing efficiency for energy conversion and energy consumption of an engineering system. The η3e is based on energy, economic and environment efficiency of a system. This method encourages a fair treatment for all energy conversion and consumption systems.
Saidur, R, Masjuki, HH, Hasanuzzaman, M, Mahlia, TMI, Tan, CY, Ooi, JK & Yoon, PH 2008, 'Performance investigation of a solar powered thermoelectric refrigerator', International Journal of Mechanical and Materials Engineering, vol. 3, no. 1, pp. 7-16.
This paper describes the development stages and performance of a solar powered thermoelectric refrigerator. It is carried out by installing a conventional thermoelectric refrigerator in a stand alone photovoltaic system for household usage. This photovoltaic driven refrigerator is powered by a field of solar panels, a battery bank, a solar charge controller, and an inverter. In this project, the output power of the photovoltaic system and the capability of the battery bank are determined. A compact thermoelectric refrigerator of 22 watts is applied to be investigated in respect to cooling effect produced. To make the device portable, daytime use and nighttime use of the refrigerator are treated in different ways. The effect of door-opening upon the cooling temperature produced by the photovoltaic driven thermoelectric refrigerator is investigated too. In order to efficiently operate this solar powered refrigerator, the sizing of this stand-alone photovoltaic system and the optimum tilt angle of the photovoltaic array must firstly be determined to maximize the electricity generation for matching the load requirement.
Yanti, PAA & Mahlia, TMI 2008, 'Methodology of implementing energy efficiency standards for electric motor', European Journal of Scientific Research, vol. 24, no. 1, pp. 134-147.
Interests in establishing appliance standards are spreading from North America and Europe to many other countries around the world. The methodology of electric motor efficiency standards is still being developed, and therefore, no single methodology is available for establishing standards for electric motor. This paper discusses the methodology involved in developing energy efficiency standards for electric motor. The initial step of setting a standard is proposing a test procedure, then the energy efficiency standards can be implemented based upon energy test procedure, then followed by proposing suitable energy labels and incentive programs for the appliances. The equations to calculate energy savings and the economic and environmental impact of the standards are also discussed. The methodology presented in this study is suitable for a developing country that lack of available data. Using this approach may shorten the time required for developing standards. © EuroJournals Publishing, Inc. 2008.
Yanti, PAA & Mahlia, TMI 2008, 'Technical note: Life cycle cost analysis of design options selection for energy efficiency improvement of electric motor', International Journal of Mechanical and Materials Engineering, vol. 3, no. 2, pp. 206-211.
Literature on energy efficiency standards and labels for electric motor are widely available. However, very limited articles discussed about the method to calculate life-cycle cost analysis of potential energy efficiency improvement for electric motor. This paper presents the life-cycle cost analysis of energy efficiency improvement of electric motor based on engineering/economic analysis. The least efficient model from a survey in the market was selected as a baseline model. The method includes the selection of design options that will increase efficiency and calculate its life cycle cost (LCC) analysis and payback period. LCC was calculated as a function of several design options based on potential efficiency improvement. The study found that, efficiency improvement can be achieved, if manufacturers willing to adopt more efficient design options with a little additional investment for the product. Furthermore, the method can be used for other product without major modification.
Mahlia, TMI, Taufiq, BN, Ismail & Masjuki, HH 2007, 'Correlation between thermal conductivity and the thickness of selected insulation materials for building wall', ENERGY AND BUILDINGS, vol. 39, no. 2, pp. 182-187.View/Download from: Publisher's site
Memon, LA, Mahlia, TMI & Masjuki, HH 2007, 'A review on fuel economy standards and labels for motor vehicles: Implementation possibility in Pakistan', Journal of Applied Sciences, vol. 7, no. 4, pp. 626-632.View/Download from: Publisher's site
This research investigates the possibilities of potential savings and reduction in Green House Gas (GHG) emissions caused by road transport in general and private cars in particular. Private cars use a large share of the transport fuel, thus these are the major and ever increasing contributor to the GHG emissions. An extensive review of international experiences on fuel economy standards and labels, in order to encounter the problem, is carried. The possibilities of the implementation of fuel economy standards and labels for motor vehicles in Pakistan are examined. Based on the studies carried out in developed countries, results have shown that the implementation of fuel economy standards and labels for motor vehicles in developing countries like Pakistan would be beneficial for the society, government as well as environment. © 2007 Asian Network for Scientific Information.
Taufiq, BN, Masjuki, HH, Mahlia, TMI, Amalina, MA, Faizul, MS & Saidur, R 2007, 'Exergy analysis of evaporative cooling for reducing energy use in a Malaysian building', DESALINATION, vol. 209, no. 1-3, pp. 238-243.View/Download from: Publisher's site
Taufiq, BN, Masjuki, HH, Mahlia, TMI, Saidur, R, Faizul, MS & Mohamad, EN 2007, 'Second law analysis for optimal thermal design of radial fin geometry by convection', APPLIED THERMAL ENGINEERING, vol. 27, no. 8-9, pp. 1363-1370.View/Download from: Publisher's site
Aslam, MU, Masjuki, HH, Kalam, MA, Abdesselam, H, Mahlia, TMI & Amalina, MA 2006, 'An experimental investigation of CNG as an alternative fuel for a retrofitted gasoline vehicle', FUEL, vol. 85, no. 5-6, pp. 717-724.View/Download from: Publisher's site
Hendra, R, Hamdani, Mahlia, TMI & Masjuki, HH 2005, 'Thermal and melting heat transfer characteristics in a latent heat storage system using Mikro', APPLIED THERMAL ENGINEERING, vol. 25, no. 10, pp. 1503-1515.View/Download from: Publisher's site
Kalam, MA, Masjuki, HH, Amalina, MA, Abdesselam, H & Mahlia, TMI 2005, 'Co, hc and nox emissions characteristics of a retrofitted bi-fuel natural gas engine', HKIE Transactions Hong Kong Institution of Engineers, vol. 12, no. 3, pp. 25-30.View/Download from: Publisher's site
This paper presents the experimental results carried out to evaluate CO, HC and NOx exhaust emissions and performance characteristics of a computer integrated bi-fuel spark ignition engine that has been retrofitted for two fuels namely, gasoline and compressed natural gas (CNG). The ignition point was optimised for CNG through the external device so that the maximum cylinder pressure occurred at similar as gasoline fuel such as between 10 to 10.50 deg crank angles after top dead centre (TDC). The used engine is a 4-cylinder spark ignition engine that has been operated with steady state condition using engine operating software and data acquisition system called CADET6. An eddy current dynamometer was used to measure engine performance characteristics such as engine brake power and fuel consumption and to give load on engine during measuring emission characteristics. Bosch and Bacharach exhaust gas analysers were used to measure emissions gases such as CO, HC and NOx. The performance test was done with full throttle condition and corresponding air-fuel (AFR) was evaluated. The emissions test was done with fixed load condition for both the fuels. The results show that CNG reduces 15% brake power with 15% to 18% reduction in specific fuel consumption (SFC) as compared to gasoline fuel. This is mainly due to the gases nature of CNG fuel. The emissions results show that CNG reduces CO and HC emissions but increases NOx emissions. The details about the emissions and performance results with three way catalytic (TWC) converter have been presented and discussed. The results of this experiment will be used to develop of new dedicated natural gas engines. © 2005 Taylor & Francis Group, LLC.
Mahlia, TMI, Said, MFM, Masjuki, HH & Tamjis, MR 2005, 'Cost-benefit analysis and emission reduction of lighting retrofits in residential sector', ENERGY AND BUILDINGS, vol. 37, no. 6, pp. 573-578.View/Download from: Publisher's site
Varman, M, Masjuki, HH & Mahlia, TMI 2005, 'Electricity savings from implementation of minimum energy efficiency standard for TVs in Malaysia', ENERGY AND BUILDINGS, vol. 37, no. 6, pp. 685-689.View/Download from: Publisher's site
Varman, M, Masjuki, HH & Mahlia, TMI 2005, 'One-watt TV label implementation in Malaysia', International Journal of Regulation and Governance, vol. 5, no. 1, pp. 1-12.View/Download from: Publisher's site
Many countries, from the US to Australia, are now interested in implementing stand-by power energy label for household appliances, in stages, until the 1-W (watt) target is achieved. TV sets consuming 1-W power are widely available in the developed nations. In a developing country like Malaysia, however, the penetration of 1-W stand-by power TV is very low and unless a mandatory label programme is introduced, the degree of penetration is not likely to rise. This paper attempts to calculate the emission pollutants reduction and the energy savings by implementing the 1-W stand-by power label for TV sets in Malaysia. It is estimated that this effort will enable CO2 (carbon dioxide) emissions reduction of 1477.7 kT (kilo tonnes), NOx (oxides of nitrogen) reduction of 4673.0 tonnes, and CO (carbon monoxide) reduction of 763.7 tonnes in the country during the energy label period of 20 years. Additionally, Malaysia will benefit from energy savings of approximately, 2794.9 GWh (gigawatt hours). © 2005, IOS Press. All rights reserved.
Mahlia, TMI 2004, 'Methodology for predicting market transformation due to implementation of energy efficiency standards and labels', ENERGY CONVERSION AND MANAGEMENT, vol. 45, no. 11-12, pp. 1785-1793.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH, Saidur, R & Amalina, MA 2004, 'Cost-benefit analysis of implementing minimum energy efficiency standards for household refrigerator-freezers in Malaysia', ENERGY POLICY, vol. 32, no. 16, pp. 1819-1824.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH, Saidur, R & Amalina, MA 2004, 'Mitigation of emissions through energy efficiency standards for room air conditioners in Malaysia', ENERGY POLICY, vol. 32, no. 16, pp. 1783-1787.View/Download from: Publisher's site
Saidur, R, Nasrudin, AR, Masjuki, HH, Choudhury, IA, Mahlia, TMI & Husnawan, M 2004, 'Development of energy test procedure for household refrigerator-freezers in Malaysia', International Journal of Power and Energy Systems, vol. 24, no. 1, pp. 46-55.
Refrigerator-freezer energy consumption is greatly influenced by room temperature, thermostat setting positions, and door openings. To develop a realistic test procedure with respect to climatic conditions and usage patterns prevailing in a given country, the effect of these parameters on refrigerator-freezer energy consumption has to be taken into consideration. In order to do so, we have tested six household refrigerator-freezers of different capacities and brands in the laboratory. Using response surface methodology (RSM), we developed a mathematical model to co-relate energy consumption as a function of room temperature, thermostat setting positions, and door opening. Finally, modelled energy consumption was compared with the ISO specified standard energy consumption and field energy consumption to justify the possibilities of introducing ISO refrigerator-freezer energy test procedure in Malaysia. Based on the above comparison, we observed that ISO test standards can be adopted for testing and rating of these appliances in Malaysia.
Varman, M, Masjuki, HH & Mahlia, TMI 2004, 'Emission mitigation from implementation of minimum energy performance standard (MEPS) for TVs in Malaysia', Clean Technologies and Environmental Policy, vol. 6, no. 4, pp. 282-287.View/Download from: Publisher's site
Mahlia, TMI, Abdulmuin, MZ, Alamsyah, TMI & Mukhlishien, D 2003, 'Dynamic modeling and simulation of a palm wastes boiler', RENEWABLE ENERGY, vol. 28, no. 8, pp. 1235-1256.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH, Saidur, R, Choudhury, IA & NoorLeha, AR 2003, 'Projected electricity savings from implementing minimum energy efficiency standard for household refrigerators in Malaysia', ENERGY, vol. 28, no. 7, pp. 751-754.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH & Choudhury, IA 2002, 'Development of energy labels for room air conditioner in Malaysia: methodology and results', ENERGY CONVERSION AND MANAGEMENT, vol. 43, no. 15, pp. 1985-1997.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH & Choudhury, IA 2002, 'Potential electricity savings by implementing energy labels for room air conditioner in Malaysia', ENERGY CONVERSION AND MANAGEMENT, vol. 43, no. 16, pp. 2225-2233.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH, Choudhury, IA & Ghazali, NNN 2002, 'Economical and environmental impact of room air conditioners energy labels in Malaysia', ENERGY CONVERSION AND MANAGEMENT, vol. 43, no. 18, pp. 2509-2520.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH, Choudhury, IA & Saidur, R 2002, 'Testing and rating non-ducted air conditioners in Malaysia: The applicability of ISO standard 5151', International Journal of Power and Energy Systems, vol. 22, no. 2, pp. 80-84.
Air conditioners are one of the major energy-consuming appliances in the Malaysian domestic sector. According to a load survey, air conditioners account for around 8.3% of the total residential electricity consumption in Malaysia. To reduce the energy consumption in this sector, Malaysia Energy Center is considering implementing minimum energy efficiency standards for room air conditioners sometime in the coming year. The first step towards adopting energy efficiency standards is to create a test procedure for rating and testing this appliance. An energy test procedure is the technical foundation for alt energy efficiency standards, energy labels, and other related programs. As room air conditioners are a climate-dependent appliance, the climatic condition for a particular country or region is an important determinant in developing the test conditions. Therefore, before setting the test conditions, the requirements for a specific country and region must be clarified. This article is an analysis of the applicability of ISO 5151 nonducted air conditioner test conditions, based on the climatic conditions in Malaysia. International adoption of ISO 5151 by several countries is also discussed. There is a trend towards international harmonization of appliance test standards; this work can be considered as support to that end.
Masjuki, HH, Mahlia, TMI, Choudhury, IA & Saidur, R 2002, 'Potential CO2 reduction by fuel substitution to generate electricity in Malaysia', ENERGY CONVERSION AND MANAGEMENT, vol. 43, no. 6, pp. 763-770.View/Download from: Publisher's site
Mahlia, TMI, Abdulmuin, MZ, Alamsyah, TMI & Mukhlishien, D 2001, 'An alternative energy source from palm wastes industry for Malaysia and Indonesia', ENERGY CONVERSION AND MANAGEMENT, vol. 42, no. 18, pp. 2109-2118.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH, Choudhury, IA & Saidur, R 2001, 'Potential CO2 reduction by implementing energy efficiency standard for room air conditioner in Malaysia', ENERGY CONVERSION AND MANAGEMENT, vol. 42, no. 14, pp. 1673-1685.View/Download from: Publisher's site
Masjuki, HH, Mahlia, TMI & Choudhury, IA 2001, 'Potential electricity savings by implementing minimum energy efficiency standards for room air conditioners in Malaysia', ENERGY CONVERSION AND MANAGEMENT, vol. 42, no. 4, pp. 439-450.View/Download from: Publisher's site
Masjuki, HH, Saidur, R, Choudhury, IA, Mahlia, TMI, Ghani, AK & Maleque, MA 2001, 'The applicability of ISO household refrigerator-freezer energy test specifications in Malaysia', ENERGY, vol. 26, no. 7, pp. 723-737.View/Download from: Publisher's site
Farizal, F, Aji, R, Rachman, A, Nasruddin, N & Mahlia, TMI, 'Indonesia's Municipal Solid Waste 3R and Waste to Energy Programs', Makara Journal of Technology, vol. 21, no. 3, pp. 153-153.View/Download from: Publisher's site
Farizal, F, Eka Septia, W, Rachman, A, Nasruddin, N & Indra Mahlia, TM, 'Optimization of Electricity Generation Schemes in the Java-Bali Grid System with Co2 Reduction Consideration', Makara Journal of Technology, vol. 20, no. 2, pp. 49-49.View/Download from: Publisher's site
Gunawan, Y, Putra, N, Hakim, II, Agustina, D & Mahlia, TMI, 'Withering of tea leaves using heat pipe heat exchanger by utilizing low-temperature geothermal energy', International Journal of Low-Carbon Technologies.View/Download from: Publisher's site
The volume of Indonesian tea exports to the European Union (EU) decreased by 43% in 2014 because of the EU setting a maximum residue limit of anthraquinone (AQ) for tea as 0.02 mg/kg. The content of AQ in tea leaves increases when there is incomplete combustion in the combustion of firewood for the energy source of withering and drying of tea leaves. This study aims to develop and test a new concept for the direct use of low-temperature geothermal energy with a heat pipe heat exchanger (HPHE) for the withering of tea leaves as a solution for energy sources free from AQ. The geothermal fluid simulators use water, which is heated by heater and flowed by a pump. The HPHE used consists of 42 heat pipes and 181 fins. The heat pipe used has a length of 700 mm with an outer diameter of 10 mm. Each fin is made of aluminum with a thickness of 0.105 mm and a size of 76 × 345 mm2. The results show that the effectiveness of the HPHE varies from 66% to 79.59%. For 100 g of fresh tea leaves, the heating energy produced ranges from 15.21 W to 45.07 W, meaning it can wither tea leaves from 80% (w.b.) to 54% (w.b.) in a variety of 11 h 56 min to only 49.6 min. The Page mathematical model is the best model to represent the behavior of the tea leaves with this HPHE system.
Mahidin, M, Gani, A, Hani, MR, Syukur, M, Hamdani, H, Khairil, K, Rizal, S, Hadi, A & Mahlia, TMI, 'Use of Green Mussel Shell as a Desulfurizer in the Blending of Low Rank Coal-Biomass Briquette Combustion', Makara Journal of Technology, vol. 20, no. 2, pp. 97-97.View/Download from: Publisher's site
Mahlia, TMI, Masjuki, HH, Choudhury, IA & R. Saidur, ARS, 'A review on energy efficiency standards and labels: present status and implementation possibilities in malaysia', ASEAN Journal on Science and Technology for Development, vol. 18, no. 1, pp. 71-84.View/Download from: Publisher's site
This article is a review on energy efficiency standards and labels for household electrical appliances around the world. Through the review of other country experiences on energy efficiency standards and labels, we attempt to identify savings possibilities in Malaysian households. The implementation possibilities of standards and labels for various household electrical appliances in Malaysia are also examined. It is found that various household appliances in Malaysia offer some potential in reducing electricity consumption. Finally, it is concluded that there are many advantages for Malaysia to implement the standards and labels for household electrical appliances as soon as possible in order to reduce electricity bills and energy consumption in Malaysian households.
Safira, L, Putra, N, Trisnadewi, T, Kusrini, E & Mahlia, TMI, 'Thermal properties of sonicated graphene in coconut oil as a phase change material for energy storage in building applications1', International Journal of Low-Carbon Technologies.View/Download from: Publisher's site
This study aims to investigate the thermal properties of a phase change material (PCM) based on coconut oil for building energy storage applications. Coconut oil is classified as an organic PCM composed of fatty acids made from renewable feedstock. However, low thermal conductivity is one of the major drawbacks of organic PCMs that must be improved. Graphene could be an effective material to enhance the thermal performance of organic PCMs. In this study, coconut oil with a latent heat capacity of 114.6 J/g and a melting point of 17.38°C was used. PCMs were prepared by sonicating graphene into coconut oil, as a supporting material. The mass fractions of the prepared PCMs were 0, 0.1, 0.2, 0.3, 0.4 and 0.5. Thermal conductivity tests were performed using a KD2 thermal property analyser under different ambient temperatures of 5, 10, 15, 20 and 25°C simulated with a circulating thermostatic bath. The latent heat, melting point and freezing point were determined through differential scanning calorimetry, the thermal stability was determined using thermogravimetric analysis (TGA) and the morphology and chemical structure were examined using transmission electron microscopy and Fourier-transform infrared spectroscopy, respectively. The results of this study showed that graphene addition to coconut oil improved the thermal performance, with the highest improvement seen in a 0.3 wt% sample at 20°C. The latent heat decreased by 11% owing to molecular movements within the PCM. However, TGA revealed that the composite PCMs showed good thermal stability in ambient building temperature ranges.
Saidur, RS, Masjuki, HH, Mahlia, TMI & Nasrudin, AR, 'FACTORS AFFECTING REFRIGERATOR-FREEZERS ENERGY CONSUMPTION', ASEAN Journal on Science and Technology for Development, vol. 19, no. 2, pp. 57-67.View/Download from: Publisher's site
Two frost-free household refrigerator-freezers, one with 492 liter capacity and one with 460 liter capacity were tested in the laboratory to determine the sensitivity of several variables those influence consumption refrigerator-freezers energy consumption greatly. The effects of single variables such as room temperature, thermostat setting positions, and door openings on the energy consumption were investigated. Using Response Surface Methodology (RSM), a mathematical model has been developed to investigate the combined effect of room temperature, thermostat setting positions, and door opening on the energy consumption of refrigerator-freezers. From the mathematical model, it has been observed that room-temperature has the highest effect on the energy consumption followed by the thermostat setting position. The door opening has lowest on the energy consumption. More detailed tests were performed under different room temperature, thermostat setting positions, and door opening conditions and presented in this paper.
Sukarno, R, Putra, N, Hakim, II, Rachman, FF & Mahlia, TMI, 'Multi-stage heat-pipe heat exchanger for improving energy efficiency of the HVAC system in a hospital operating room1', International Journal of Low-Carbon Technologies.View/Download from: Publisher's site
The demands of specific requirements related to thermal comforts, such as temperature, relative humidity, inside air exchange and other factors required in a hospital operating rooms, have necessitated the development of energy-efficient heating, ventilation and air conditioning (HVAC) systems and efficient heat-recovery system using a heat-pipe heat exchanger (HPHE). The experiment was conducted by using HPHEs having three, six and nine rows, with four heat pipes in each row, arranged in a staggered configuration with a variation of fresh-air inlet temperature and velocity. The theoretical analysis was conducted using the ε-NTU method for predicting the effectiveness, outlet temperature of the evaporator side and energy recovery of the HPHE. The experimental results indicated that increasing the air-inlet temperature in the evaporator section and the number of rows increased the HPHE effectiveness but increasing the air-inlet velocity reduced the effectiveness. The highest effectiveness of 62.6% was obtained at an air-inlet temperature of 45°C with an air-inlet velocity of 2 m/s and a 9-row HPHE. The energy recovery of the HPHE increased with the number of rows, air-inlet temperature and air velocity in the evaporator section. The ε-NTU method can be used as a comparison method in the analysis of heat-recovery systems that apply HPHE air conditioning systems. Heat pipes that utilize cold-air exhaust from a room in an HVAC system can enhance efficiency and reduce emissions.
Rahman, MM, Mahlia, TMI & Uddin, MN 2020, 'Energy Efficiency Analysis in Building Walls in Tropical Climate Using Thermal Insulation System' in Encyclopedia of Renewable and Sustainable Materials, Elsevier, The Netherlands, pp. 255-261.View/Download from: Publisher's site
Thermal comfort is essential in a tropical climate and air conditioning system in buildings offers better thermal comfort compared to other systems. But the air conditioning system in the building consumes a lot of energy to fulfil the thermal comfort needs in a tropical climate. An efficient thermal insulation system in the building can increase the energy efficiency by lowering the consumption for cooling systems. Thus, this research aims to study the effectiveness of different thermal insulation material on energy saving for building walls in Malaysia. The energy savings and the life-cycle cost of using ten thermal insulation materials in Malaysian building walls have been evaluated. In addition, the energy savings due to the air gap in the wall construction has been investigated for the selected insulation material. The findings indicated that the life-cycle cost and energy savings are varying from 73% to 85%/m2 wall and 85% to 92%/m2 wall respectively depending on the optimal thickness of insulation material. Among the insulation materials, styropor insulation showed better economic benefits. It was also found that 6 cm gap in the wall construction can save additional 0.64%/m2 wall life cycle cost by improving the insulation effect by retarding the heat flow into the building.
Fauzi, H, Metselaar, HSC, Mahlia, TMI, Silakhori, M & Ong, HC 2018, 'Investigation of thermal characteristic of eutectic fatty acid/damar gum as a composite phase change material (CPCM)' in Exergy for a Better Environment amd Improved Sustainability 2: Applications (Green Energy and Technology), Springer, Switzerland, pp. 607-616.View/Download from: Publisher's site
© 2018, Springer International Publishing AG, part of Springer Nature. A composite phase change material (CPCM) of myristic acid/palmitic acid/sodium myristate (MA/PA/SM) has been proposed by impregnating a porous material of purified damar gum, also called Shorea javanica (SJ), to improve the thermal conductivity of CPCM. The thermal properties, thermal conductivity and thermal stability, of CPCM were measured using differential scanning calorimetry (DSC) thermal analysis, hot-disc thermal conductivity analyzer, and simultaneous thermal analyzer (STA). Moreover, a chemical reaction between fatty acid binary mixture and SJ in CPCM was evaluated by Fourier transform infra-red (FT-IR) spectrophotometer. The results of this study showed that the thermal conductivity of MA/PA/SM/SJ composite phase change material (CPCM) was improved by addition of 3 wt.% of Shorea javanica into MA/PA/SM eutectic mixture without showing a significant change in the thermophysical properties of CPCM. Moreover, the eutectic CPCM also does not show occurrence of chemical reaction between MA/PA/SM and SJ, and it has a good thermal performance and thermal stability. Therefore, the MA/PA/SM/SJ CPCM proposed in this study can be recommended as a new novelty material for thermal energy storage application.
Idris, MA, Mahlia, TMI, Om, NI, Hussein, I & Jamil, MR 2016, 'Effectiveness of Computerized Homework Implementation in Thermodynamics: Correlation Between Doing the Homework and the Grade' in 7th International Conference on University Learning and Teaching (InCULT 2014) Proceedings, Springer Singapore, pp. 627-637.View/Download from: Publisher's site
Kalam, MA, Hassan, MH, Hajar, RB, Yusuf, MSB, Umar, MRB & Mahlia, I 2008, 'Palm oil diesel production and its experimental test on a diesel engine' in Handbook of Plant-Based Biofuels, pp. 225-240.View/Download from: Publisher's site
© 2009 by Taylor & Francis Group, LLC. This chapter presents the status of palm oil diesel (POD) production and its experimental test on a multicylinder diesel engine. The test results obtained are brake power, specific fuel consumption (SFC), exhaust emissions, anti-wear characteristics of fuel-contaminated lubricants, and fuel Rancimat test characteristics. It was found that B20X fuel showed better overall performance such as improved brake power, reduced exhaust emissions and shows better lube oil quality as compared to other tested fuels. The specific objective of this investigation is to improve the performance of B20 fuel using an antioxidant additive.
Tan, ES, Kumaran, P, Indra, TMI, Tokimatsu, K & Yoshikawa, K 2018, 'Impact of biodiesel application on fuel savings and emission reduction for power generation in Malaysia', INNOVATIVE SOLUTIONS FOR ENERGY TRANSITIONS, 10th International Conference on Applied Energy (ICAE), ELSEVIER SCIENCE BV, Hong Kong, HONG KONG, pp. 3325-3330.View/Download from: Publisher's site
Mojaddadi Rizeei, H, Pradhan, B & Mahlia, TM 2018, 'GIS-Based Suitability Analysis on Hybrid Renewal Energy Site Allocation Using integrated MODIS and ASTER Satellite Imageries in Peninsular Malaysia', 39th ACRS 2018 PROCEEDING, Asian Conference on Remote Sensing, ACRS, Kuala Lumpur, pp. 358-368.
This study attempts to find the most suitable place to establish a hybrid renewable energy site in Malaysia where richly endowed with resources such as a diverse form of biomass and solar energy. We used Satellite-derived solar irradiance estimation which is a useful and accurate approach for solar resource calculation. To do so, MODIS Terra and Aqua satellite were assessed to extract values of Aerosol Optical Depth (AOD) at 550 nm. Subsequently, other topographic contribution factors were derived from ASTER satellite imagery. MODIS satellite imagery was also classified by support vector machine to extract land use/land cover. Additionally, sixteen different metrological stations were utilized to calibrate the solar irradiances achieved from MODIS satellite and provide daily wind data over the entire Peninsular Malaysia. Finally, simple additive weighting method was implemented in a geographical information system platform to develop the hybrid RE suitability model. MODIS solar radiation result showed a high coloration with field observation. The result of hybrid renewable energy suitability analysis revealed that coastal areas of Hulu Terengganu, have a high potential for allocating sites. This country scale research can be used as a guidance/preliminary assessment to narrow down the scope of new potential hybrid RE in regional scale.
Abdullah, K, Saepul Uyun, A, Muhammad Nur, S, Bamahry, A, Imanda, R & Meurah Indra Mahlia, T 2017, 'Experimental Investigation of Air Conditioner using the Desiccant Cooling System in Equatorial Climates', MATEC Web of Conferences, International Conference on Electrical Systems, Technology and Information, Bali, Indonesia.View/Download from: Publisher's site
© The Authors, published by EDP Sciences, 2018. Indonesia lies in the tropical climate which requires air conditioning to increase working productivity of the people. Up to now people are still using the compressive cooling system which uses Freon as the refrigerant, which have been known to have a negative environmental impact. Therefore, new cooling system which is environmentally friendly is now needed. Desiccant cooling system manipulates the humidity condition of outside air in such a way so that the final temperature should become at 25 °C and RH of 65 %. Since it does not require refrigerant, a desiccant cooling has the potential to be developed in a tropical country like Indonesia. In this study an experimental desiccant cooling system has been designed and constructed and tested under laboratory condition. Experimental results have shown that the resulting air temperature was 26.1 °C with RH of 55.6 %, and average cooling capacity was 0.425 kW. The COP was found to be 0.44.
Khairil, Rizki, A, Iskandar, Jalaluddin, Silitonga, AS, Masjuki, HH & Mahlia, TMI 2017, 'The potential biodiesel production from Cerbera odollam oil (Bintaro) in Aceh', MATEC Web of Conferences, The 2nd International Joint Conference on Advanced Engineering and Technology, Bali, Indonesia.View/Download from: Publisher's site
© The Authors, published by EDP Sciences, 2018. Biodiesel production from non-edible vegetable oils is an effective way to conquer the linked problems with edible oils such as food versus fuel and other environmental impacts. Cerbera odollam oil is one of these possible non-edible feed stocks for future biodiesel production. This study evaluated the potential biodiesel production from cerbera odollam. The seed was collected and extracted from Aceh, Indonesia. Moreover, biodiesel has been produced using degummed (H3PO4) and two step acid catalyst (HCl) and alkaline catalyst (KOH). The results of properties of the cerbera odollam methyl esters show that such as viscosity was about 847.9 mm 2 /s, density was 3.1578 kg/m 3 , flash point was 214.0°C, acid value was 0.4 mg KOH/g, oxidation stability was 6.35 h, FAME content was 97.77 % w/w and heating value was 40.49 MJ/kg. After analysing these properties, it has been found that there is a huge chance to produce biodiesel from this seed which complies with the limits of ASTM 6751 and EN 14214 specifications and therefore it can boost the future production of biodiesel from non-edible sources.
Susanto, H, Abdullah, K, Saepul Uyun, A, Muhammad Nur, S & Meurah Indra Mahlia, T 2017, 'Turbine Design for Low Heat Organic Rankine Cycle Power Generation using Renewable Energy Sources', MATEC Web of Conferences, Bali, Indonesia.View/Download from: Publisher's site
© The Authors, published by EDP Sciences, 2018. In recent years, due to its feasibility and reliability, the organic rankine cycle has become a widespread concern and is the subject of research. In the organic rankine cycle system, the radial turbine component is a highly influential component of the high low performance resulting. This paper discusses the design of radial turbines for organic rankine cycle systems. The design stage consists of preliminary design and detail design with parametric methods on the working fluid R22 to determine the geometry and initial estimation of the performance of the radial turbine. After that, a numerical study of the fluid flow region in the radial turbine with R22 as the working fluid was performed. The analysis was performed using computational fluid dynamics of Autodesk Computational Fluid Dynamics Motion software on two models of real gas, k-epsilon and shear stress transport. From the results of this analysis, there is pressure, velocity and temperature distribution along the radial turbine blades and estimated performance under various operating conditions. Comparison between parametric and computational fluid dynamics analysis results show different performance. The difference is due to the computational fluid dynamics analysis already involving the real gas shear stress transport model.
Thaib, R, Fauzi, H, Ong, HC, Rizal, S, Mahlia, TMI & Riza, M 2017, 'Thermal characteristic investigation of eutectic composite fatty acid as heat storage material for solar heating and cooling application', IOP Conference Series: Materials Science and Engineering, International Conference on Chemical Engineering Sciences and Applications, Ulee Kareng, Indonesia.View/Download from: Publisher's site
© Published under licence by IOP Publishing Ltd. A composite phase change material (CPCM) of myristic acid/palmitic acid/sodium myristate (MA/PA/SM) and of myristic acid/palmitic acid/sodium laurate (MA/PA/SL) were impregnated with purified damar gum as called Shorea Javanica (SJ) to improve the thermal conductivity of CPCM. The thermal properties, thermal conductivity, and thermal stability of both CPCM have investigated by using a Differential Scanning Calorimetry (DSC) thermal analysis, hot disc thermal conductivity analyzer, and Simultaneous Thermal Analyzer (STA), simultaneously. However, a chemical compatibility between both fatty acid eutectic mixtures and SJ in composite mixtures measured by Fourier Transform Infra-Red (FT-IR) spectrophotometer. The results were obtained that the thermal conductivity of MA/PA/SM/SJ and MA/PA/SL/SJ eutectic composite phase change material (CPCM) were improved by addition 3 wt.% and 2 wt.% of Shorea javanica (SJ), respectively, without occur a significant change on thermal properties of CPCM. Moreover, the absorbance spectrum of FT-IR shows the good compatibility of SJ with both MA/PA/SM and MA/PA/SL eutectic mixtures, the composite PCM also present good thermal performance and good thermal stability. Therefore, it can be noted that the purified Shorea Javanica proposed, the as high conductive material in this study was able to improve the thermal conductivity of eutectic PCM without any significant reduction on its thermo-physical and chemical properties and can be recommended as novelty composite phase change material for thermal energy storage application.
Thaib, R, Rizal, S, Riza, M, Mahlia, TMI & Rizal, TA 2017, 'Beeswax as phase change material to improve solar panel's performance', IOP Conference Series: Materials Science and Engineering, International Conference Numerical Analysis in Engineering, Banda Aceh.View/Download from: Publisher's site
© 2018 Institute of Physics Publishing. All rights reserved. One of the main obstacles faced during the operation of photovoltaic (PV) panels was overheating due to excessive solar radiation and high ambient temperatures. In this research, investigates the use of beeswax phase change materials (PCM) to maintain the temperature of the panels close to ambient. Solar panels used in this study has 839 mm length, 537 mm wide, and 50 mm thick, with maximum output power at 50 W. During the study, there were two solar panels was evaluated, one without phase change material while the other one was using beeswax phase change material. Solar panels were mounted at 15° slope. Variables observed was the temperature of solar panel's surface, output voltage and current that produced by PV panels, wind speed around solar panels, and solar radiation. The observation was started at 07:00 am and ended at 06:00 pm. The research shows that maximum temperature of solar panels surface without phase change material is ranging between 46-49 °C, and electrical efficiency is about 7.2-8.8%. Meanwhile, for solar panels with beeswax phase change material, the maximum temperature solar panels surface is relatively low ranging between 33-34 °C, and its electrical efficiency seems to increase about 9.1-9.3%.
Fareeza, N, Tan, ES, Kumaran, P, Indra, TM, Fadzilah, N & Yoshikawa, K 2016, 'Evaluating the Effect of Syngas Composition on Micro gas turbine Performance', INTERNATIONAL CONFERENCE ON ADVANCES IN RENEWABLE ENERGY AND TECHNOLOGIES (ICARET 2016), 2nd International Conference on Advances in Renewable Energy and Technologies (ICARET), IOP PUBLISHING LTD, Putrajaya, MALAYSIA.View/Download from: Publisher's site
Ghazali, KA, Salleh, SF, Riayatsyah, TMI, Aditiya, HB & Mahlia, TMI 2016, 'The effect of dilute acid pre-treatment process in bioethanol production from durian (durio zibethinus) seeds waste', INTERNATIONAL CONFERENCE ON ADVANCES IN RENEWABLE ENERGY AND TECHNOLOGIES (ICARET 2016), 2nd International Conference on Advances in Renewable Energy and Technologies (ICARET), IOP PUBLISHING LTD, Putrajaya, MALAYSIA.View/Download from: Publisher's site
Hidayat, MHM, Salleh, SF, Riayatsyah, TMI, Aditiya, HB, Mahlia, TMI & Shamsuddin, AH 2016, 'Techno-economic analysis of bioethanol production from rice straw by liquid-state fermentation', INTERNATIONAL CONFERENCE ON ADVANCES IN RENEWABLE ENERGY AND TECHNOLOGIES (ICARET 2016), 2nd International Conference on Advances in Renewable Energy and Technologies (ICARET), IOP PUBLISHING LTD, Putrajaya, MALAYSIA.View/Download from: Publisher's site
Rahman, MM, Rahman, HY, Mahila, TMI & Sheng, JLY 2016, 'Liquid cooled plate heat exchanger for battery cooling of an electric vehicle (EV)', INTERNATIONAL CONFERENCE ON ADVANCES IN RENEWABLE ENERGY AND TECHNOLOGIES (ICARET 2016), 2nd International Conference on Advances in Renewable Energy and Technologies (ICARET), IOP PUBLISHING LTD, Putrajaya, MALAYSIA.View/Download from: Publisher's site
Silitonga, AS, Masjuki, HH, Ong, HC, How, HG, Kusumo, F, Teoh, YH & Mahlia, TMI 2015, 'Engine Performance, Emission and Combustion in Common Rail Turbocharged Diesel Engine from Jatropha Curcas Using Artificial Neural Network', SAE Technical Papers.
Copyright © 2015 SAE Japan and Copyright © 2015 SAE International. This paper investigates the performance, emission and combustion of a four cylinder common-rail turbocharged diesel engine using jatropha curcas biodiesel blends (JCB). The test was performed with various ratios of jatropha curcas methyl ester (JCME) in the blends (JCB10, JCB20, JCB30, and JCB50). An artificial neural networks (ANN) model based on standard back-propagation algorithm was used to predict combustion, performance and emissions characteristics of the engine using MATLAB. To acquire data for training and testing of the proposed ANN, the different engine speeds (1500-3500 rpm) was selected as the input parameter, whereas combustion, performance and emissions were chosen as the output parameters for ANN modeling of a common-rail turbocharged diesel engine. The performance, emissions and combustion of the ANN were validated by comparing the prediction dataset with the experimental results. The results show that the correlation coefficient was successfully controlled within the range 0.9798-0.9999 for the ANN model and test data. The value of MAPE (Mean Absolute Percentage Error) was within the range 1.2373-6.4217 and the Root Mean Square (RSME) value was below 0.05 by the model, which is acceptable. This study shows that modeling techniques as an approach in alternative energy can give improvement advantage of reliability in the prediction of performance and emission of internal combustion engines.
Fauzi, H, Metselaar, HSC, Mahlia, TMI & Silakhori, M 2014, 'Thermal reliability of myristic acid/palmitic acid/sodium laurate eutectic mixture: a feasibility study of accelerated aging for thermal energy storage application', INTERNATIONAL CONFERENCE ON APPLIED ENERGY, ICAE2014, 6th International Conference on Applied Energy (ICAE), ELSEVIER SCIENCE BV, Taipei, TAIWAN, pp. 49-54.View/Download from: Publisher's site
Ong, HC, Silitonga, AS, Mahlia, TMI, Masjuki, HH & Chong, WT 2014, 'Investigation of Biodiesel Production from Cerbera Manghas Biofuel Sources', INTERNATIONAL CONFERENCE ON APPLIED ENERGY, ICAE2014, 6th International Conference on Applied Energy (ICAE), ELSEVIER SCIENCE BV, Taipei, TAIWAN, pp. 436-439.View/Download from: Publisher's site
Silakhori, M, McTselaar, HSC, Mahlia, TMUI & Fauzi, H 2014, 'Preparation, characterization and thermal reliability of form-stable Myristic acid/Polypyrrole composites as phase change materials for thermal energy storage', Materials Science and Technology Conference and Exhibition 2014, MS and T 2014, pp. 1643-1650.
Copyright © 2014 MS & T14®. A novel form-stable Myristic acid (MA)/Polypyrrole (PPy) phase change materials (PCMs) were readily synthesized by in-situ polymerization method. MA and PPy were used as thermal energy storage material and supporting material, respectively. SEM (Scanning electron microscopy) and FTIR (Fourier transform infrared spectrometer) were illustrated MA Particles were wrapped by PPy particles. Differential scanning calorimetry(DSC) were used for investigating thermal energy storage properties of prepared form-stable PCMs. The form-stable PCMs were considered as the highest loading PCM with desirable latent heat storage and good thermal stability. Thermal cycling tests were done up to 2500 cycles which showed form-stable PCMs had a favorable thermal reliability. Thanks to favorable thermal properties, thermal stability and chemical stability, the new type of form stable PCMs can be considered for low temperature thermal energy storage applications.
Silitonga, AS, Ong, HC, Mahlia, TMI, Masjuki, HH & Chong, WT 2014, 'Biodiesel conversion from high FFA crude jatropha curcas, calophyllum inophyllum and ceiba pentandra oil', INTERNATIONAL CONFERENCE ON APPLIED ENERGY, ICAE2014, 6th International Conference on Applied Energy (ICAE), ELSEVIER SCIENCE BV, Taipei, TAIWAN, pp. 480-483.View/Download from: Publisher's site
Ismail, MS, Moghavvemi, M & Mahlia, TMI 2013, 'Optimization of a PV/microturbine hybrid system for tropical climates', 2013 3RD INTERNATIONAL CONFERENCE ON ELECTRIC POWER AND ENERGY CONVERSION SYSTEMS (EPECS), 3rd International Conference on Electric Power and Energy Conversion Systems (EPECS), IEEE, Yildiz Tech Univ, Davutpasa Campus, Istanbul, TURKEY.
Shafie, SM, Mahlia, TMI & Masjuki, HH 2013, 'The Environmental Analysis of Rice Straw, Preparation As Feedstock into Electricity Generation Using Life Cycle Assessment, LCA: Malaysia', INTERNATIONAL CONFERENCE ON FRONTIERS OF ENERGY, ENVIRONMENTAL MATERIALS AND CIVIL ENGINEERING (FEEMCE 2013), International Conference on Frontiers of Energy, Environmental Materials and Civil Engineering (FEEMCE), DESTECH PUBLICATIONS, INC, Shanghai, PEOPLES R CHINA, pp. 612-617.
Atabani, AE, Saidur, R, Silitonga, AS & Mahlia, TMI 2011, 'Energy Economical and Environmental Analysis of Industrial Boilers using VSD', MECHANICAL AND AEROSPACE ENGINEERING, PTS 1-7, 2nd International Conference on Mechnaical and Aerospace Engineering (ICMAE 2011), TRANS TECH PUBLICATIONS LTD, Bangkok, THAILAND, pp. 3223-3233.View/Download from: Publisher's site
Hamdani, Irwansyah & Mahlia, TMI 2012, 'INVESTIGATION OF MELTING HEAT TRANSFER CHARACTERISTICS OF LATENT HEAT THERMAL STORAGE UNIT WITH FINNED TUBE', INTERNATIONAL CONFERENCE ON ADVANCES SCIENCE AND CONTEMPORARY ENGINEERING 2012, International Conference on Advances Science and Contemporary Engineering (ICASCE), ELSEVIER SCIENCE BV, Jakarta, INDONESIA, pp. 122-128.View/Download from: Publisher's site
Khosravi, S, Yau, YH, Mahlia, TMI & Saidi, MH 2011, 'A New Approach to Exergy Analyses of a Hybrid Desiccant Cooling System Compares to a Vapor Compression System', MECHANICAL AND AEROSPACE ENGINEERING, PTS 1-7, 2nd International Conference on Mechanical and Aerospace Engineering (ICMAE 2011), TRANS TECH PUBLICATIONS LTD, Bangkok, THAILAND, pp. 2163-+.View/Download from: Publisher's site
Rismanchi, B, Saidur, R, Masjuki, HH & Mahlia, TMI 2011, 'Cost-benefit analysis of using cold thermal energy storage systems in building applications', 2011 2ND INTERNATIONAL CONFERENCE ON ADVANCES IN ENERGY ENGINEERING (ICAEE), 2nd International Conference on Advances in Energy Engineering (ICAEE), ELSEVIER SCIENCE BV, Bangkok, THAILAND, pp. 493-498.View/Download from: Publisher's site
Shafie, SM, Mahlia, TMI, Masjuki, HH & Rismanchi, B 2011, 'Life cycle assessment (LCA) of electricity generation from rice husk in Malaysia', 2011 2ND INTERNATIONAL CONFERENCE ON ADVANCES IN ENERGY ENGINEERING (ICAEE), 2nd International Conference on Advances in Energy Engineering (ICAEE), ELSEVIER SCIENCE BV, Bangkok, THAILAND, pp. 499-504.View/Download from: Publisher's site
Shekarchian, M, Moghavvemi, M, Motasemi, F & Mahlia, TMI 2011, 'Cost Benefit Analysis and Energy Savings of Using Compression and Absorption Chillers for Air Conditioners in Hot and Humid Climates', 4TH INTERNATIONAL MEETING OF ADVANCES IN THERMOFLUIDS (IMAT 2011), PT 1 AND 2, 4th International Meeting of Advances in Thermofluids (IMAT), AMER INST PHYSICS, Melaka, MALAYSIA, pp. 521-531.View/Download from: Publisher's site
Zhao, X, Ma, C & Gu, P 2011, 'Energy Saving Methods and Results Analysis in the Hotel', 2011 2ND INTERNATIONAL CONFERENCE ON ADVANCES IN ENERGY ENGINEERING (ICAEE), 2nd International Conference on Advances in Energy Engineering (ICAEE), ELSEVIER SCIENCE BV, Bangkok, THAILAND, pp. 1523-1527.View/Download from: Publisher's site
Khosravi, S, Mahlia, TMI & Yau, YH 2010, 'Feasibility Study of Hybrid Wheel Desiccant Dehumidification Cooling Systems in Malaysia', ASHRAE TRANSACTIONS 2010, VOL 116, PT 1, ASHRAE Winter Conference, AMER SOC HEATING, REFRIGERATING AND AIR-CONDITIONING ENGS, Orlando, FL, pp. 392-397.
Adnan, R, Masjuki, HH & Mahlia, TMI 2009, 'An experimental investigation of unmodified di diesel engine with hydrogen addition', ICEE 2009 - Proceeding 2009 3rd International Conference on Energy and Environment: Advancement Towards Global Sustainability, pp. 45-49.View/Download from: Publisher's site
The consumption of fossil fuels spawns environmental considerations in addition to issues of energy demand, national security and resource availability. At global level, scientists warn that the combustion of fossil fuels is significantly changing the world's climate system. Local or regional concerns include smog, acid rain, and health implications of urban air pollution. Due to stringent emission norms and depletion of petroleum resources there has been a continuous effort to use alternative fuels such as hydrogen. It has its own benefits and limitations if it is used in conjunction with conventional fuel in diesel engine. The purpose of this article was to investigate the effect of hydrogen addition on performance and exhaust gas emission of stationary diesel engine. In this study, hydrogen was used as secondary fuel in a single cylinder 406 c.c. diesel engine. The hydrogen was injected through intake manifold and diesel was injected directly inside the combustion chamber. Series of experiments were conducted and it can be seen the effect of hydrogen addition in the increase of peak pressure from 5 bar to a maximum 21 bar, IMEP from 1.0 to 1.7 bar , indicated power from 4%-16%. There were also increases in NOx and CO emissions from 48-197 ppm and 423-758 ppm, respectively. Hydrogen addition causes increase in exhaust gas temperature from 3.1% to 10.2% particularly at 2500 rpm and reduction in O 2 emissions from 3.9% to 7.6% (by volume) throughout all engine speeds. ©2009 IEEE.
Husnawan, M, Masjuki, HH, Mahlia, TMI, Saifullah, MG & Kalam, MA 2009, 'The use of dihydroxy fatty acid and palm-based polyol as selected components of envo-diesel fuel blends to reduce C.I. engine gaseous emissions and carbon deposits', SAE Technical Papers.View/Download from: Publisher's site
Nowadays, engine problems such as higher NOx, increase in smoke content and low brake power output due to biofuel fueled engine have been reduced by several improvements by using additives or modifications on engine itself. This paper presents a type of compositions and proper combination of selected chemical components which may be used in palm olein-diesel blends namely "Envo-Diesel". The blended component was designed as an additive package which was blended with diesel-biofuel at 99:1 up to 95:5 percent ratios. Blended fuels with additive have been used in the single cylinder engine which operated under 2000 rpm for 100 hours. Engine performance and emissions tests were conducted as well as engine deposit analysis was done after 100 hours engine operation time. The result was found that by using combined additive engine fuel consumption was decreased about 5%, NOx and SO x emission also reduced about 10% and carbon deposit was found less compared to other fuels especially for higher percentage of additive. Other results such as engine power and CO emission were found quite similar with 100% diesel fuel. These phenomena was shown that by using selected additive in certain amount found to be suitable to reduce diesel engine consumption and exhaust emissions as well as minimizing carbon deposit. Copyright © 2009 SAE International.
Husnawan, M, Masjuki, HH, Mahlia, TMI, Saifullah, MG & Mohammad, EN 2009, 'The use of renewable basestock lubricant containing metal-free additive and their effects on triboproperties and diesel engine CO2 emission', World Tribology Congress 2009 - Proceedings, p. 576.
In every IC engine, there will be a certain amount of unburned fuel that passes through piston rings and enters the lubricating oil that affects lubricant degradation trough reactions with chemical species and will cause greater wear in the engine as well as influencing the combustion efficiency indefinitely. Renewable based-lubricant with the presence of non-metallic additive reduce wear rate. There is a significant material weight loss and lower friction coefficient. The renewable based lube oil with additive also succeeds in reducing CO2 emission ∼ 5% compared to the mineral based. This is an abstract of a paper presented at the 2009 World Tribology Congress (Kyoto, Japan 9/6-11/2009).
Kalam, MA, Masjuki, HH, Mahlia, TMI, Fuad, MA, Halim, K, Ishak, A, Khair, M, Yusoff, A & Shahrir, A 2009, 'Experimental test of a new compressed natural gas engine with direct injection', SAE Technical Papers.View/Download from: Publisher's site
This paper presents experimental test results of a new compressed natural gas direct injection (CNG-DI) engine that has been developed from modification of a multi cylinder gasoline port injection (PI) engine. The major modifications done are (1) the injection system has been modified to gas direct injection using new high pressure gas injectors, (2) compression ratio has been changed from 10 to 14 through modification of piston and cylinder head, and (3) new spark plugs with long edge were used to ignite the CNG fuel. The CNG pressure at common rail was kept at 20 bar to be injected into engine cylinder. The engine has been operated with full throttle conditions to compare all the results with original base engine such as gasoline port injection engine and the CNG bi-fuel engine where the base engine has been converted to bi-fuel injection system to be operated with gasoline and CNG fuels. Hence, it can be mentioned that the original gasoline port injection engine has been modified to CNG bi-fuel and CNG-DI systems. The bi-fuel injection was developed using a gas conversion kit with gas port injection injectors. The test results obtained from CNG fuel using two different systems (i.e. bi-fuel and DI) will be investigated and compared with original gasoline engine. The test was conducted with computer controlled dynamometer to measure brake power, specific fuel consumption (SFC), exhaust emissions such as carbon monoxide (CO), oxides of nitrogen (NOx), and unburned hydrocarbon (HC). The objective of this investigation is to compare the test results between "CNG-DI", with "CNG-BI" and "gasoline - PI" engines with the same displacement volume. It was found that the CNG-DI engine produces 4% higher brake power at 6000 rpm as compared to original gasoline fueled engine. The CNG-BI engine produces maximum power of 57 kW at 5500 rpm which is 23% lower than CNG-DI engine's peak power (at 6000 rpm). The average BSFC of CNG-DI engine was 0.28% and 8% lower than gasoline-P...
Mahlia, TMI, Husnawan, M, Masjuki, HH, Chow, KV, Low, TS & Liaw, AWJ 2008, 'ENERGY ANALYSIS OF COOLING PUMP IN INTERNAL COMBUSTION ENGINE', IMECE 2008: PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION - 2008, VOL 8, ASME International Mechanical Engineering Congress and Exposition, AMER SOC MECHANICAL ENGINEERS, Boston, MA, pp. 249-253.
Mahlia, TMI, Husnawan, M, Masjuki, HH, Remuslara, L & Saidur, R 2008, 'ENERGY SAVINGS POTENTIAL BY SUBSTITUTING DRIVING WITH WALKING AND CYCLING FOR SHORT DISTANCE', IMECE 2008: PROCEEDINGS OF THE ASME INTERNATIONAL MECHANICAL ENGINEERING CONGRESS AND EXPOSITION, VOL 7, ASME International Mechanical Engineering Congress and Exposition, AMER SOC MECHANICAL ENGINEERS, Boston, MA, pp. 3-7.
Kalam, MA, Masjuki, HH, Redzuan, M, Mahlia, TMI, Fuad, MA, Mohibah, M, Halim, K, Ishak, A, Khair, M, Shahrir, A & Yusof, A 2008, 'Development and test of a new catalytic converter for natural gas fueled engine', SAE Technical Papers.View/Download from: Publisher's site
This paper presents exhaust gas emissions characteristcs of a new direct injection (DI) compressed natural gas (CNG) engine using a low cost catalytic conveter (Catco). The pollutants exhaust gas emissions measured were CO, HC and NOx with and without Catco. The Catco was developed based on catalyst materials consisting of metal oxides such as titanium dioxide (TiO2) and cobalt oxide (CoO) with wiremesh substrate. Both of the catalyst materials (such as TiO2 and CoO) are inexpensive in comparison to conventional catalysts (noble metals) such as palladium or platinum. In addition, the noble metals such as platinum group metal are now indentified as human health risk due to their rapid emissions in the environment from various resources like conventional catalytic converter, jewelers and other medical usages. It can be mentioned that both the CNG-DI engine and TiO2/CoO based catalytic converter were developed under a research collaboration program. The original engine manufacture catalytic conveter (OEM Catco) was tested for comparison purposes. The OEM Catco was based on noble metal catalyst with honeycomb ceramic substrate. It is experimentally found that the conversion efficiencies of TiO2/CoO based catalytic converter are 93%, 89% and 82% for NO x, CO and HC emissions respectively. It is calculated that the TiO2/CoO based catalytic converter reduces 24%,41% and 40% higher NOx, CO and HC emissions in comparison to OEM Catco respectively. The objective of this paper is to develop a low cost three way catalytic converter to be used with the newly developed CNG-DI engine. Detailed review on catalytic converter, low cost catalytic converter development characteristics and CNG-DI engine test results have been presented with discussions. © 2008 SAE International.
Kalam, MA, Masjuki, HH, Syazly, M, Redzuan, M, Ramang, H & Mahlia, TMI 2006, 'Fuel additive that cuts emission and increases brake power in a small bio-fuel diesel engine', SAE Technical Papers.View/Download from: Publisher's site
Copyright © 2006 SAE International and Copyright © 2006 SAE Japan. This paper presents experimental test results of a diesel engine using additive added bio Diesel oil obtained from palm oil. The test results obtained are brake power, specific fuel consumption (SFC) and exhaust emissions. In addition, antiwear characteristics of fuel's contaminated lubricants were observed using a tribometer test. A computer control dynamometer-engine test bed was used to measure engine brake power and SFC at half throttle condition with speed range of 1000 rpm to 4000 rpm. The emission test was done with dynamometer fixed load of 50 Nm and constant engine speed of 2250 rpm. A total of three fuels or 100% diesel fuel (B0); 20% palm oil diesel (POD) and 80% B0 (B20); and B20 with X% additive (B20X) were selected for this investigation. The B20X is the additive added bio Diesel oil where X is the percentage (in this investigation X=1% of B20) of additive in B20 fuel. Anti wear characteristics in terms of coefficient of friction, wear scar diameter and flash temperature parameter (FTP) of fuel's contaminated lubricants were measured using a tribometer test. It was found that B20X fuel showed better overall performance such as cut emissions and increased engine brake power as well as increased anti-wear characteristics as compared to other test fuels. The specific objective of this investigation is to improve the performance of B20 fuel with an antioxidant additive. Detailed results have been presented with discussions.
Masjuki, HH, Kalam, MA, Syazly, M, Mahlia, TMI, Rahman, AH, Redzuan, M, Varman, M, Saidur, R & Yau, YH 2006, 'Experimental evaluation of an unmodified diesel engine using biodiesel with fuel additive', IFOST 2006: 1ST INTERNATIONAL FORUM ON STRATEGIC TECHNOLOGY, PROCEEDINGS, 1st International Forum on Strategic Technology (IFOST 2006), IEEE, Ulsan, SOUTH KOREA, pp. 96-+.View/Download from: Publisher's site
Kalam, MA, Hassan, MH, Hamlaoui, A, Afifi, ABM, Mahlia, TMI & Uddin, MA 2005, 'Development of co-relation between vehicle and stationary dynamometer-engine emissions', Proceedings of the 2005 Spring Technical Conference of the ASME Internal Combustion Engine Division, Spring Technical Conference of the ASME-Internal-Combustion-Engine-Division, AMER SOC MECHANICAL ENGINEERS, Chicago, IL, pp. 101-106.
Kalam, MA, Masjuki, HH, Amalina, MA, Abdesselam, H, Mahlia, TMI & Aslam, MU 2005, 'Emission characteristics of a modified CNG gasoline-cycle engine', 2005 SPE Asia Pacific Oil and Gas Conference and Exhibition - Proceedings, pp. 549-557.
Taufiq, BN, Mahlia, TMI, Masjuki, HH, Faizul, MS & Mohamad, EN 2005, 'Optimization of radial convective radiating fin geometry for single cylinder internal combustion engine (ICE): Entropy generation minimization', PROCEEDINGS OF THE 2005 SPRING TECHNICAL CONFERENCE OF THE ASME INTERNAL COMBUSTION ENGINE DIVISION, Spring Technical Conference of the ASME-Internal-Combustion-Engine-Division, AMER SOC MECHANICAL ENGINEERS, Long Beach, CA, pp. 405-413.
Varman, M, Faizul, MS, Masjuki, HH, Kalam, MA & Mahlia, TMI 2005, 'Study of lubricant viscosity from a diesel engine operating on various percentages of coconut oil blended fuel', Proceedings of the World Tribology Congress III - 2005, pp. 861-862.
In this study, the lubricant viscosity from a diesel engine operating on various percentages of coconut oil blended fuel is investigated to determine the suitable mixture appropriate for a diesel engine. The coconut oil was blended with conventional diesel fuel at an amount varying from ten to fifty percent. The lubricant used in this study is the conventional commercially available lubricant (SAE 40). After proper blending of diesel with coconut oil, the blended fuels are loaded into the fuel tank. The engine is operated at half throttle setting running at 1600 rpm for 100 hours. At every ten hour interval, one lubricant sample was collected and analyzed using a viscometer at 100 °C and 40 °C. The results show that the viscosity for all the blended fuel remain about constant throughout the 100 hours test. However, fifty percent coconut oil blended fuel at 40 °C shows slightly lower viscosity level in comparison to other percentages of blended fuel system. It is expected this is due to high fuel dilution in lube oil. As a result, ten to thirty percent coconut oil blended fuels seems suitable for diesel engine because it's able to prolong lubricant life span by maintaining its viscosity. Copyright © 2005 by ASME.
Varman, M, Faizul, MS, Masjuki, HH, Kalam, MA & Mahlia, TMI 2005, 'Study of lubricant viscosity from a diesel engine operating on various percentages of coconut oil blended fuel', Proceedings of the World Tribology Congress III - WTC 2005.
The lubricant viscosity from a diesel engine operating on various percentages of coconut oil blended fuel was studied to determine the suitable mixture appropriate for a diesel engine. The coconut oil was blended with conventional diesel fuel at an amount varying from 10 to 50%. The lubricant used was the conventional commercially available lubricant (SAE 40). The viscosity for all the blended fuel remained about constant throughout the 100 hr test. However, 50% coconut oil blended fuel at 40°C showed slightly lower viscosity level in comparison to other percentages of blended fuel system. Lubricant viscosity has an initial drop between zero and 10 hr running time. There were fluctuations in viscosity level occurring, especially in the upper curves. An increase in lubricant viscosity was usually caused by the formation of sludge and the presence of wear debris. This is an abstract of a paper presented at the World Tribology Congress III (Washington, DC 9/12-16/2005).
Kalam, MA, Masjuki, HH, Maleque, MA, Amalina, MA, Abdesselam, H & Mahlia, TMI 2004, 'Air-fuel ratio calculation for a natural gas fuelled spark ignition engine', SAE Technical Papers.View/Download from: Publisher's site
Air-fuel ratio (AFR) is a crucial parameter for combustion controls in internal combustion engines. An incorrect AFR metering for reciprocating internal combustion engine causes high toxic gases emissions formulation, serious fuel consumption problems and unbearable combustion noise and combustion deterioration. Traditionally, the AFR is obtained by direct measurement of intake air and the fuel either injected into the combustion chamber or pre-mixed at the carburetor. However, the accurate AFR obtained from direct measurement is difficult due to measuring equipments resolution prone to errors. This paper describes a method for accurate determination of air-fuel ratio based on exhaust emission gas analysis as an additional tool used to be validated the conventional direct air fuel flow rates measurement. This method explains all the possible parameters that may affect the accuracy of air-fuel ratio measurement which includes the instrument error, ambient conditions, the assumed water-gas shift reaction constant, the humidity of the atmospheric air and the inclusion of nitrogen in the air-fuel ratio model. Results show that four essential exhaust gas emission concentrations, namely carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2) and unburn hydrocarbons (HCs) are adequate for obtaining an accurate air-fuel ratio. The fuel type and the range of parameters that may affect the accuracy of air-fuel ratio are properly defined. This paper will also present experimental results of a bi-fuel natural gas spark ignition engine to be compared with computational results. The results of this investigation will be used to develop a new dedicated natural gas engine. Copyright © 2004 SAE International.
Saidur, R, Masjuki, HH, Choudhury, IA & Mahlia, TMI 2000, 'The effect of usage condition on energy consumption of two household refrigerator freezer', ADVANCES IN MALAYSIAN ENERGY RESEARCH 2000, Seminar on Advances in Malaysian Energy Research 2000, INST TENAGA MALAYSIA, SHAH ALAM, MALAYSIA, pp. 297-306.
Masjuki, HH, Mahlia, TMI, Choudhury, IA & Saidur, R 2000, 'A literature review on energy efficiency standards and labels for household electrical appliances', IEEE 2000 TENCON PROCEEDINGS, VOLS I-III, 10th International IEEE Tencon Conference, IEEE, KUALA LUMPUR, MALAYSIA, pp. A103-A107.
Masjuki, HH, Saidur, R, Choudhury, IA & Mahlia, TMI 2000, 'Factors effecting energy consumption of household refrigerator-freezers', IEEE 2000 TENCON PROCEEDINGS, VOLS I-III, 10th International IEEE Tencon Conference, IEEE, KUALA LUMPUR, MALAYSIA, pp. A92-A96.
Masjuki, HH, Choudhury, IA, Mahlia, TMI & Rahman, S 1999, 'Energy conservation opportunity for room air conditioner in Malaysia', WREC'99: WORLD RENEWABLE ENERGY CONGRESS'99 MALAYSIA, PROCEEDINGS, World Renewable Energy Congress 1999, UNIV KEBANGSAAN MALAYSIA, KUALA LUMPUR, MALAYSIA, pp. 431-435.
Masjuki, HH, Mahlia, TMI, Saidur, R & Choudhury, IA 1970, 'The applicability of the ISO 5151 and ISO 8187 test conditions for air conditioner and household refrigerator in Malaysia', ADVANCES IN MALAYSIAN ENERGY RESEARCH 1999, 2nd Annual Seminar on Advances in Malaysian Energy Research, INST TENAGA MALAYSIA, MALAYSIA, pp. 147-158.