What reverse-cycle heating costs in a Sydney winter

Winter is the bigger row on the label

Every air conditioner sold here carries two annual energy figures on its label, one for cooling and one for heating, measured for the climate zone Sydney sits in. The running costs guide works from the cooling row.

This post is about the other one, and it is the larger of the two: of the 264 models we install with both figures in the GEMS registration data (synced 9 June 2026), every single one uses more energy heating than cooling in the Sydney-zone test.

Across our wall splits heating is 64 per cent of the annual figure; across ducted systems it is 62 per cent.

The dollar figures below multiply that heating energy by the current Sydney median usage rate, 35.13 cents per kWh across 170 Ausgrid plans in the June 2026 plan data, the same way every model page on this site prices a year of running.

The Endeavour median for Western Sydney and the Illawarra, 34.45 cents, is two per cent lower; a later section shows what that moves.

A bedroom split: $95 to $188 for the season

Twenty-one of the wall splits we install sit at 2.5 or 2.6 kW, the size for a bedroom or a study, and their heating figures run from 271 kWh to 534 kWh a year.

Mitsubishi Heavy Industries' Avanti Plus is the only model at this size with 4 heating stars, yet three units with 3.5 stars use less. Most of the field sits between 350 and 380 kWh.

At the bottom is the TCL T-Pro, which carries 5.5 cooling stars but only 2.5 for heating. Same room, same size, $93 a year apart, and the cooling stars point the wrong way.

A living room at 7 kW: $324 to $401

Fifteen wall splits in our range sit between 7 and 7.2 kW, and their winters cost $324 to $401 at the Sydney rate. The lowest is the TCL T-Pro 7.2 kW at 923 kWh, the brand that finishes last at bedroom size, so read the model, not the badge.

The Skywall's cooling row is 726 kWh, about $255, so for that one unit winter is $146 dearer than summer.

Ducted units at the same capacity run a little higher again: the twelve between 7 and 7.1 kW span 940 kWh (Carrier QSM, $330) to 1,179 kWh (Rinnai D Series, $414), and the ducted cost guide covers what else separates them.

A whole house: ducted at 10, 14 and 20 kW

Ducted heating is where the winter figure gets serious. The lowest and highest ducted units we install at each size:

Panasonic's Adaptive is the only ducted unit in our range with 3.5 heating stars; the Daikin Inverter Ducted at 10 kW carries 1.5.

Two things soften those numbers in a real house: a zoned ducted system heating the living areas by day and the bedrooms at night conditions only part of the house at a time, and the figure is for the average zone, not your street, which a later section comes back to.

Why the same power buys three to five times the heat

A reverse-cycle unit does not make heat from electricity, it moves heat from the outside air into the room, and that is why it wins on a winter bill.

The heating figure in the GEMS data comes with an efficiency ratio, the ACOP, and across our range it runs from 3.12 (Daikin's 25 kW ducted unit) to 5.61 (MHI's Avanti Plus 2 kW): every kWh of electricity delivers between three and five and a half kWh of heat.

A fan heater, an oil column or a panel heater returns one for one; energy.gov.au puts reverse-cycle units at 300 to 600 per cent efficient against roughly 100 per cent for a standard electric heater.

The ActronAir Serene 2.6 kW's 271 kWh of electricity is, at its ACOP of 5.39, about 1,460 kWh of heat into the bedroom; the same heat through a resistive heater takes about 1,460 kWh of electricity, roughly $513 against $95.

At living-room size the Daikin Skywall's 1,141 kWh becomes about 3,770 kWh of heat, $1,325 through a heater against $401. Even the unit with the fewest heating stars in our range beats a plug-in heater by more than three to one.

Ausgrid or Endeavour, coast or west

The electricity rate is the smaller of the two local factors. At the Endeavour median of 34.45 cents instead of Ausgrid's 35.13, a two per cent shift:

• ActronAir Serene 2.6 kW: $93 a winter instead of $95
• Rinnai D Series 14 kW: $947 instead of $966

Western Sydney and Wollongong pay that rate; the Eastern Suburbs, the Northern Beaches, the Inner West and the Central Coast are on Ausgrid.

The climate moves it more, and the label cannot show it, because the average zone is one set of figures for the whole of Sydney.

The Bureau of Meteorology's July mean minimum is 8.1 degrees at Observatory Hill and 3.8 degrees at Richmond RAAF, four degrees colder on the same morning, and a unit in Richmond runs longer than the same unit in Bondi.

Treat the figures above as a fair comparison between models, not a forecast of one bill: expect the west to sit above them and the coast below.

Reading this when you choose

Compare the heating row before the cooling stars if winter is when you feel the bills, and only against other models of the same capacity; what a star is worth shows how far the two rows can disagree.

Size the unit to the room with the calculator, plan a ducted system's zones around the rooms you heat at night, and clean the filter before the cold arrives, because a blocked filter makes the unit run longer for the same warmth (a clean is a small job).

Every model page here shows both figures with the date beside them, and the compare tool puts models side by side.

Sources

• GEMS registered air conditioners dataset (E3 program), data.gov.au, CC BY 3.0: the annual heating and cooling kWh, heating stars and ACOP per model, synced 9 June 2026
• Understand the Zoned Energy Rating Label, energyrating.gov.au: the three climate zones and what the heating and cooling kWh on the label represent
• Heating and cooling, energy.gov.au: reverse-cycle units at 300 to 600 per cent efficient against about 100 per cent for a standard electric heater
• Energy Made Easy, the AER's plan data: the median usage rate across 170 Ausgrid and 162 Endeavour plans, June 2026
• Bureau of Meteorology climate statistics, Sydney (Observatory Hill) and Richmond RAAF: July mean minimum temperatures
• Our model pages under systems: each model's heating and cooling figures costed from the same sources, with the date