Cold? Worried about high winter energy bills? Concerned about climate change? Quick, turn on your air conditioner.
That's the argument Tim Forcey, an energy advisor with University of Melbourne Energy Institute, makes in a report published a few years ago titled Switching Off Gas.
Forcey writes that people living in up to one million homes across eastern Australia can save hundreds of dollars each winter with one easy action. 'They need to turn on their existing reverse-cycle air conditioner heat pumps and turn off their gas.' It's that simple.
How does it work? While many Australians still think of air conditioners as machines for cooling, in other countries they're used for heating, and they're called 'heat pumps'.
Standard electric heaters turn roughly one unit of electricity into one unit of heat. So they're about 100 per cent efficient. A reverse cycle air conditioner, however, uses electricity to 'pump' heat from one place to another. And it's incredibly efficient at doing so — the ratio can be one unit of electricity to four or five units of heat. So they can be 400, 500 or even 600 per cent efficient.
Hot water heat pumps work in the same way. When a household has both, the savings — environmental and economic — can be substantial. In 2014, the Grattan Institute found a typical home in Melbourne could save over $1000 a year by switching from gas to efficient electric appliances for heating, hot water and cooking. In Sydney it was over $600, and in Adelaide over $500.
The same year, the Alternative Technology Association analysed the cost of gas versus efficient electric appliances for six different housing types across the east-coast grid — that's South Australia, Tasmania, Victoria, New South Wales, ACT and Queensland.
Energy analyst Kate Leslie, who worked on the report, says switching from gas to efficient electric appliances was more economic everywhere they looked. 'And that was mainly due to the efficiency of reverse cycle air conditioners.'
"What about renters? Or vulnerable groups in slum suburbs? Or pensioners? Students? They either can't afford the upfront costs or don't have permission to make large alterations to their houses. The clean tech transition is wonderful, but it's leaving many such people behind."
But what if there's an electricity price rise? Another ATA energy analyst, Keiran Price, is working on an updated report comparing the costs of gas vs electric appliances and solar power. He says a price rise is likely but still