Power Bill Comparison
What it takes to heat and cool your house now, next to a new 7-star all-electric home the same size.
Know it in squares? Convert it here.
Your energy rates
It's printed on your bill.
Filled in with the government's Victorian Default Offer for your distributor. Change it to the rate on your bill.
Your comparison appears once you've added a Victorian postcode, the living area, when it was built, how you heat it, how you cool it.
Energy ratings and running costs: common questions
What is a 7-star energy rating?
It is a rating under the national house energy rating scheme (formerly NatHERS) of how much heating and cooling the building itself needs in its climate zone, before any heater or air conditioner is counted. New homes in Victoria have had to reach 7 stars since 1 May 2024.
How much less heating does a new home need than an old one?
It depends on how old the house is and where it is. Sustainability Victoria's audit of Victorian houses put a typical home built before 1990 at about 1.6 stars, so a new 7-star home of the same size needs far less heating and cooling. Type in your postcode and when your house was built to see the difference for yours.
Do new homes in Victoria have to be all-electric?
From 1 January 2027, every new home in Victoria has to be all-electric, knockdown rebuilds included. Since 31 December 2023, a new home that needs a planning permit already can't be connected to mains gas.
Weighing up a rebuild?
Talk to us about what a new home on your block would involve, from the slab to the heat pump.
How we worked this out
The heating and cooling each home needs comes from the national energy rating scheme's 2022 star bands (Home Energy Rating, formerly NatHERS) for your postcode's climate zone, multiplied by the living area. New homes in Victoria have had to reach 7 stars since 1 May 2024. Older homes take a typical rating for when they were built: about 1.6 stars before 1990 and 3.1 stars from 1990 to 2004 (Sustainability Victoria's audit of Victorian houses), 5 stars from 2005 to 2010 (the building code minimum then), 6.1 stars from 2011 (the Victorian 6-star evaluation) and 7 stars from 2025.
Heating takes the share of the load that new homes in your climate zone show on their ratings (CSIRO Australian Housing Data). Existing heaters and coolers use the efficiencies Sustainability Victoria measured in Victorian homes, including duct losses for ducted systems. For an evaporative cooler, that is Sustainability Victoria's estimate for a Melbourne climate; real output depends on the temperature and humidity outside. The new home uses the middle efficiency of reverse-cycle systems on sale now, from the government's Energy Rating register, cold-climate figures.
The rating method assumes every living space is heated and cooled (standard use), which runs above real bills. Sustainability Victoria measured gas use in older Victorian homes at about 61,000 MJ a year with central heating and 24,000 MJ with room heaters. Against our standard-use figure for the same houses, that is about 0.76 and 0.36. The lower end of the saving scales both homes by that factor; electric heaters use the room-heater factor, as no measured figure exists for them.
Electricity is filled in with the Victorian Default Offer for 2026-27 from the Essential Services Commission, including GST. Supply charges are left out because you pay them either way, except the gas supply charge, which a new home doesn't have: from 1 January 2027 every new home in Victoria has to be all-electric, knockdown rebuilds included.