New research shows net zero energy homes in Melbourne, Townsville, Canberra and Perth housing developments are achievable and affordable, but highlights a market slow to pick up on easy opportunities for improved energy efficiency and thermal comfort.
Even though average costs for the net zero energy homes researched were between 6-11 percent higher than the standard, and offered approximately 88 percent annual energy cost savings, market interest was stuck with current consumer desire focussed on lowest price, “benchtops” or “new shiny things”.
The research also emphasised that while industry currently demands building code changes to improve regulation, quality and safety, sustainable design must be included to meet the sector’s net zero emissions target by 2050.
Funded by the CRC for Low Carbon Living, led by Curtin University’s, Dr Josh Byrne and in partnership with industry and government, this extensive research project provided a Net Zero Energy Home for potential buyers to view. Each home was designed to mitigate local climate, save energy, remove reliance on gas and use rooftop solar to meet the same, or more, of the average annual energy demand.
Most major efficiency gains came from the additional insulation, glazing upgrades and energy efficient appliances, such as induction cook tops and air source heat pumps, with only a small 3-4 KW photovoltaic (PV) system required.
“Whilst most potential buyers were positive about the homes, the research indicated that the mindset and situation of buyers was a barrier, despite the estimated future energy cost savings averaging 88% per year – which is around $1,750,” he said.
“First home buyer budget limitations and the fact banks don’t lend on future savings, were flagged as market uptake issues by builders in the study, also saying many investor buyers were not concerned about what type of homes they put their renters in, so would be the last to come on board,” says Byrne.
This is despite the net zero energy home costing only about $20,000 (6-11%) more than a standard comparable home, with better insulation, high performance glass, increased shading, efficient appliances and solar energy systems where the annual energy savings would payback this cost back in about ten years.
“Some of the builders in our study aired their frustration with industry and market apathy as they see upgrades from current home builds to Net Zero Energy as simple, easy and affordable. Some believe regulation is the only way,” says Byrne.
Another well-known obstacle for high performance housing in Australia is the perception that there is limited demand and it is a niche market.
“Although our research shows net zero energy housing can be a reality for all, we’re clearly still stuck on a roundabout trying to convince home buyers, industry and governments that they should be standard across the board. This needs to change,” says Byrne.
The research has clearly demonstrated the financial feasibility for net zero energy housing because it removes the bottom-line argument, which should make it an attractive proposition for stakeholders. The builders in this study will continue to use these positive design features.
“The unique thing about this study is that prices for upgrades to the particular base model design used came from the builder, so they are retail and reflect their supply chain considerations and mark-ups so therefore vary between builders, so it means it’s all very real,” says Byrne.
“Overall there’s really no reason for future residential developments not to be zero energy homes, but more work is required to educate the public, the industry and governments to make this business as usual, not the current approach,” he concludes.
In the study various design scenarios were reviewed with the construction and running costs analysed. Then potential buyers were surveyed. This has resulted in two detailed reports: Design review and Cost Analysis. The study on understanding customer interest is ongoing. A four-part video series was also released.
The research team from Curtin University and CSIRO provided design and technical support to the builders using modelling to assess the expected performance of the final designs. They also tracked the construction costs to determine the price impacts of design and technology features.