Perth homeowners can scoop up to $1000 in energy bill savings by ditching reverse-cycle air-conditioning and using the ground to warm up and cool down their houses.
Following a two-year test, the State Government’s land development agency – DevelopmentWA – found geoexchange systems cool and warm homes up to 100 per cent and 80 per cent better than air-conditioning.
The geoexchange works by using earth, which absorbs solar radiation, as a renewable energy source.
To heat a home, the system extracts heat from the ground and distributes the warm air around the house through ducts.
To cool a home, the geoexchange reverses the heating process by extracting warm air from a house, removing the heat and distributing the cool air.
To discover how much Western Australian homeowners could save by making the switch, DevelopmentWA launched a world-first demonstration project in a housing development in Perth’s north.
Two identical homes in DevelopmentWA’s The Vive at Craigie took part in the Cool Earth project, which compared the temperature and energy use between one home fitted with a geoexchange system and the other fitted with reverse-cycle air-conditioning.
DevelopmentWA Chief Executive Frank Marra said the positive geoexchange results were a win for innovation, sustainability and homeowners’ wallets.
“This technology has the potential to change the way Western Australians heat and cool their homes – something that currently accounts for 40 per cent of household energy use, making it a significant contributor to household bills, as well as carbon emissions,” he said.
“Widespread adoption of geoexchange technology could not only slash household bills, but also reduce our environmental impact.
“DevelopmentWA believes in leading by doing.
“This is exactly the sort of big-impact result we look for in our Innovation Through Demonstration initiatives, delivering measurable outcomes to give industry the confidence to adopt new ideas.”
The Cool Earth project, which is a collaboration between DevelopmentWA, ABN Group, GeoExchange Australia, Carbonomics and the University of Western Australia (UWA), was named a joint winner for Excellence in Heating, Ventilation, Air-conditioning and Refrigeration Research at the 2019 Australian Institute of Refrigeration Air-conditioning and Heating Awards.
UWA Head of Chemical Engineering Professor Hui Tong Chua said though heating and cooling homes using geothermal energy had been popular for a while in the northern hemisphere, there had never been a trial comparing it to air-conditioning.
“This is the first side-by-side trial of the effectiveness of an open-loop ground source system compared to conventional heating and cooling technology,” Professor Chua said.
“The geoexchange system used in this project has delivered efficiencies well beyond our expectations, and has implications for sustainable energy use around the world.”