Victorian Healthy Homes energy efficiency advice

Transcript

Good afternoon everybody, and welcome to this lovely space here at UTS. I'm Rosalie Viney, Director of the Centre for Health Economics Research and Evaluation at UTS, which is part of the INSIGHT Institute. I'd like to begin by acknowledging and paying my respects to Elders past and present, to those who have passed before us, and to the members of the Aboriginal and Torres Strait Islander community attending today. I acknowledge the Gadigal people of the Eora Nation, the traditional custodians of the lands on which the UTS campus stands, and acknowledge them as the holders of knowledge for these lands. I'd also like to acknowledge the traditional owners of the lands in Victoria on which this program was delivered: the Bunurong, Wurundjeri, Wadawurrung and Taungurung peoples of the Kulin Nation and the Yorta Yorta peoples.

Before we start, I'll give you a picture of the agenda. We'll hear from a number of people, and I'll introduce them before they speak. In the event of an emergency, the exit is there—proceed down the stairs and out into the main area.

It's a real pleasure to have this seminar to present the findings of a really exciting program of research. I'll provide an overview of the project, then we'll have other speakers who are the researchers on the project presenting the findings. We'll also hear from Dr Toby Cumming from Sustainability Victoria, who funded and delivered the program, to give us some insight into the implications.

Let me introduce Professor Susan Morton, Director of UTS's Institute for Innovative Solutions for Wellbeing and Health. This is a newly established institute and CHERE is part of it. Susan has recently joined UTS from the University of Auckland to be Director of INSIGHT. She's a public health physician and a life course epidemiologist, with an outstanding track record, notably as Foundation Director and Principal Investigator of Growing Up in New Zealand. It's a great honour to have her introduce this seminar and say a few words about how this work relates to INSIGHT.

Susan Morton: Thank you very, very much, Rosalie. It's a real privilege to be here, and wonderful to probably be the last one in the door at UTS and yet the first one to be introducing this amazing seminar. It's super exciting to be here to lead this new institute called INSIGHT. While INSIGHT wasn't in existence while this Victorian Healthy Homes project was underway, there are so many things about that project that act as an example of the sort of things we're excited to take forward at UTS in INSIGHT.

As many of you will know and you'll hear about today, the Victorian Healthy Homes project has been a really innovative project with characteristics that fit nicely with what INSIGHT is trying to achieve. Firstly, it's a living example of how to address a wicked real-world problem. It brought together multiple disciplines—health economics, sustainability, energy research, epidemiology—to solve a wicked problem: the challenges faced by vulnerable and older populations who have chronic conditions, low income, are energy poor, and struggle to be comfortable and have good wellbeing.

This group of researchers used their expertise to develop this project. It's been incredibly successful because it brought together experts across disciplines and allowed them to work across traditional boundaries. It's also focused on a vulnerable population and addressed equity, trying to ensure vulnerable populations don't miss out on services they need for wellbeing and quality of life. Addressing inequity and working across disciplines are core to INSIGHT, and this project is a living example of that.

There's also been an important partnership at the heart of this project. The partnership with Sustainability Victoria has been critical to delivering this project and making a difference in people's lives through a randomised controlled trial—a robust scientific approach, but in partnership with external partners interested in the research and findings. That partnership is key to the processes we want to set up for future projects in INSIGHT.

I'm excited to be here today as one of the newest members of UTS to celebrate the success of this research that Rosalie and her team have led. I'm eager to hear the results and all the different pieces. Despite COVID, this project has succeeded, which is testimony to the group of people committed to making sure this innovative project took off. It's my great pleasure to introduce this team of people when I'm so new to this institution, but I'm excited about what can be achieved here. Today is a really good example of the work we're able to do to make a difference to people's lives.

Rosalie Viney: Thank you, Susan, for that enthusiastic introduction. I'll provide a brief overview of the study before other presenters go into the details and implications. As you've heard, it's a complex project, so we have a number of presenters to reflect the different aspects.

Before that, I want to acknowledge the incredible and complex partnership involved. There were many partners: Sustainability Victoria, who led and commissioned the research; local councils as recruitment partners; program delivery partners who assessed homes and installed upgrades; and liaison officers who undertook home visits and data collection. There was a lot of complexity in the organisation. It also had a large research team, many of whom are here today. I thank them for all their work making the project a success.

The results will be presented by some members of the team. I'll introduce them all now: I'll start with an overview, then Dr Johan Kim from the Institute for Sustainable Futures will present energy findings; Dr Katie Page from CHERE will present health and economic outcomes; Dr Toby Cumming from Sustainability Victoria, with a background in health research, will discuss implications; and Associate Professor Kerryn Wilmot from ISF, with expertise in architecture and sustainability, will also discuss implications.

Background: Why does cold temperature matter in Australia? International evidence shows higher cold-related mortality in temperate regions, and thermal efficiency in homes is a major factor. The WHO Housing and Health Guidelines recommend indoor housing temperatures above 18°C. International research indicates thermal insulation improves health, but there's little evidence in Australia. Australian housing stock is generally poor for maintaining thermal comfort—draughty homes are common, even in Sydney.

The Victorian Healthy Homes program investigated how improving thermal performance of houses for low-income Victorians with health or social care needs would impact thermal comfort. Would it improve comfort in winter? Would it improve health and reduce healthcare costs? Would it reduce energy costs and provide value for money?

This was not just a research program, but a delivery program that provided health and energy benefits. 1,000 households across Western Melbourne and Goulburn Valley participated. Eligible households received a free home upgrade (up to $3,500), focusing on thermal comfort and energy efficiency during winter—insulation, draught sealing, efficient heating, window coverings. These were modest but important upgrades at low cost, targeted at vulnerable populations (mean age 75, low income, often requiring home care).

It's the first randomised controlled trial in Australia investigating these questions. Households expressed interest, were deemed eligible, consented, then had a residential energy scorecard visit to assess the home. They were randomised to receive the upgrade before or after winter. Everyone eventually received the upgrade, but randomisation allowed evaluation of the impact on thermal comfort during winter.

Recruitment occurred over three winters (2018, 2019, 2020), mostly in 2020. COVID lockdowns delayed upgrades, so some intervention households received no or partial upgrades, reducing sample size and analysis power. Both intention-to-treat and per-protocol analyses were done, with consistent results.

Johan Kim: I'll present the energy outcomes. To understand the impact, we measured external temperature (from BOM), home characteristics (RES scorecard, 1–10), house size, solar panels, and collected gas and electricity use from energy distributors. The primary outcome was internal temperature. This project is unique in considering internal temperature, not just energy consumption.

We found interventions led to an increase of about 0.33°C in mean indoor temperature over winter. This means participants experienced about 43 minutes less per day below 18°C (the WHO threshold for unhealthy conditions). This equates to about $33 in gas bill savings per winter—small for some, but significant for vulnerable households.

Our cohort used about 14 kWh of electricity per day. For homes with only electric heaters, increasing use by 1 kWh/day only increased temperature by 0.08°C, so a 0.33°C increase can save a lot of energy.

The biggest temperature increase was in the mornings (nearly 0.5°C), which is important as mornings are coldest and associated with higher mortality rates.

Who benefits most? Households with lower RES scores (below 5) had much lower indoor temperatures and benefited most—nearly double the temperature increase compared to better quality homes.

Beyond temperature, survey data showed the intervention group was 40% less likely to go to bed early to keep warm and 57% less likely to use a portable electric heater at night. They were 37% more likely to use the main heater only when feeling cold, reflecting improved passive thermal performance.

On energy, the intervention did not reduce electricity use (most used gas for heating), but did reduce gas use by about 25 MJ per day (12% savings). Poorer quality homes saved even more (17%). Some one-star homes used very little gas—likely due to energy poverty, not efficiency.

In summary: home upgrades improved thermal comfort and energy use for vulnerable households, especially in the mornings and in poor quality dwellings.

Katie Page: I'll present health outcomes, costs, and implementation lessons, on behalf of the CHERE team. Quotes from participants: "I wouldn't have family come and visit me in winter because my house was too cold. Here I am, sitting under a split system with visitors. How good is that? In the middle of winter. So this is great. I've got my life back." "This has made it a lot more comfortable, a lot warmer, a lot safer in my head, in my mind, because I feel like nothing can hurt me when I'm home." These capture the significant impact of the program.

In this post-pandemic world, we spend more time at home, so it's important homes are comfortable, warm, and safe. Cold, damp homes are linked to poorer physical health (respiratory, cardiovascular) and mental health. Vulnerable people (elderly, disabled, chronic illness) are at higher risk.

We wanted to know: do people report better health after upgrades? Do they use health services differently? Do their conditions improve? Do they spend less on healthcare?

We used survey data (before and after winter) and administrative health data (MBS, PBS, hospital data, costs) from 2015–2021.

Quality of life: EQ-5D showed this cohort had poorer quality of life than average, but no significant difference between intervention and control groups (possibly due to short duration). SF-36 showed significantly better mental health in the intervention group, but no difference in physical health. ASCOT (social care-related quality of life) showed significant improvement in the intervention group.

Other outcomes: the intervention group had improved breathlessness (from 26% to 36% reporting no problems), spent less time away from social activities, and were less likely to delay seeing a specialist.

Healthcare use: the intervention group used fewer MBS services (about 2.6 fewer over winter), with lower total healthcare costs ($887 less). COVID-19 in 2020 reduced all service use. No difference in prescription or hospital admissions.

These findings only cover the three-month winter period, so benefits are likely underestimated.

Program costs: Development ($450k), establishment ($780k), expansion ($2.7m), plus upgrades ($2,800 per household). Total cost per household: $5,500. For 1,000 households: $5.5m. Only marginal costs for expansion are relevant for scaling up.

Is it good value? With health and energy savings, the program pays for itself in under seven years (full costs), or under three years (upgrade costs only). Many benefits are not monetised, so this is a conservative estimate.

Implementation lessons: Regular communication with householders is important; good record keeping is essential; streamline and minimise response burden for vulnerable participants; pilot programs on a small scale; need for greater workforce capacity for retrofits; allow for contingencies.

Take-home messages: The program is good value for money, with health savings 10 times energy savings. Results likely underestimate benefits. Future work will look at specific health conditions. RCT evidence is vital, but challenging in government programs. Investments in housing upgrades are key to reducing energy and health costs and improving wellbeing.

Toby Cumming: It's great to be here. This is the culmination of years of work. Adam Shalekoff, who was part of the SV project team, is also here.

The innovative part was embedding a randomised control trial in a delivery program. Having UTS as a partner, with expertise in energy and health economics, was very productive.

Personal stories: Heather, a pensioner in an all-electric house, had very inefficient heat banks—her house rarely got above 13–14°C and used a lot of electricity. After installing a split system, her energy use dropped from 43 to 11 kWh/day, saving $400 over winter. She also felt more able to go outside, as she could heat the house quickly when needed. Carol, with physical and mental health problems, received a split system in her bathroom to help with morning transfers from her wheelchair. This improved her independence and mental health.

If you think of these upgrades as just energy interventions, you're missing the point—they are public health interventions with energy co-benefits.

Implications: Victoria is more reliant on gas for heating than NSW. Over half of Victorian homes were built before 1990 (before energy standards), and more than half are less than two stars. Healthy Homes is a drop in the ocean—there are millions more homes needing upgrades.

Healthy Homes showed that minor thermal shell upgrades can raise indoor temperatures, reduce gas use, and improve health and quality of life. Health cost savings are the key argument for scaling up. Linked administrative health data strengthens the case.

Kerryn Wilmot: Thanks to the research team. We've collected a rich data set combining health, energy, temperature, and behaviour. There's much more to analyse, including correlations between temperature and health, occupant behaviour, and the rebound effect (whether people take the benefit as warmth or energy savings).

Healthy Homes provides hard evidence of the benefits of better quality homes and informs housing policy and program design. Victoria has nearly 1.4 million homes below 2.1 stars, and over two million under six stars. There's a huge need for upgrades, especially with the rental crisis. The sector is also focusing on decarbonisation and electrification.

How do we scale up? We're involved in projects to define the need and trial scalable upgrade programs. There's also scope to research benefits for the general population and for upgrades against extreme heat (e.g., in Western Sydney).

Rosalie Viney: Thank you to all our speakers. Now it's time for questions.

[Audience Q&A]

Q: What about a matching research project in Western Sydney, given recent heatwaves? A: The challenges of increasing heat are recognised, especially in Western Sydney. Having hard evidence can drive government action. We'd like to do that work if funded.

Q: What was the driver for funding? A: The driver was New Zealand research showing insulation and efficient heating improved health. Australia has higher cold-related mortality than heat-related. Even in temperate areas, being too cold is a health problem.

Q: Will you follow up with the cohort using linked health data? A: We have data up to a year post-upgrade, with longer follow-up for earlier cohorts. We hope to look at long-term effects, including mortality.

Q: What range of housing was included? A: All types—criteria were about the person, not the house. We had everything from leaky weatherboard to newer homes. Future programs should consider home quality as an eligibility criterion.

Q: Could smart technologies or sensors help? A: Possibly, but for this cohort, even surveys were challenging. For other groups, technology could be useful.

Q: Were properties private or public? Was insulation included? A: Most were owner-occupied, but tenants and social housing tenants were included. Insulation was a key upgrade.

Q: Was temperature measured in more than one place? A: Only in the main living room. More sensors would be better in future.

Q: Experience with social housing upgrades? A: It's complex, but evidence from this project helps make the case. In Victoria, recent funding is upgrading 35,000 social housing properties.

Q: Any obstruction from energy companies? A: No. Some companies might prefer reduced demand to avoid infrastructure investment.

Q: Would spending more per home give better outcomes? Could upgrades be combined with other modifications? A: The $3,500 cap limited us. The sweet spot may be $5,000 per home. Combining upgrades with other health-related modifications makes sense.

Q: How have health agencies received the research? A: Very well. Health is interested. Including health savings shortens the payback period from decades to a few years.

Thank you all for your interest and questions. Thanks to the research team, including Dan, Kees van Gool, Patsy Kenny, and Lutfun. Special mention to Dr Matt Soeberg, who conceptualised and devised the project and made an enormous contribution to health and energy research. We are proud to be part of his legacy.

Thank you for coming. Please join us for refreshments and informal discussion.