The short answer
Save energy in winter by heating efficiently, not by heating less
Most winter energy advice tells you to switch off standby power and take shorter showers. Useful, but it misses the target. In an Australian winter, the bulk of the extra energy goes to heating, so the savings that actually matter come from heating more efficiently, not from chasing a few watts on the television. The single biggest lever is the heater you choose, because some heaters turn one unit of electricity into one unit of heat, while others turn it into three, four or five. This guide shows how to heat efficiently, what temperature to set, and how zoning and draught-sealing make every heated degree count.
Here is the core takeaway in one line: the best way to save energy in winter in Australia is to heat the rooms you use with an efficient heater, usually the reverse-cycle air conditioner you already own, set to 18 to 20 C, with draughts sealed so the heat stays in. That beats every standby-power tip combined, because heating is where the winter energy goes. A reverse-cycle unit delivers about 3 to 5 units of heat for each unit of electricity it draws. An electric resistive heater delivers about 1. Choose the efficient heater, point it at one room, and keep the cold out, and your winter bill falls without you ever feeling colder.
Reframe the assumption: "using less" sounds like the goal. It is not, on its own. You can use the same warmth and pay a third of the cost just by switching from a plug-in resistive heater to a reverse-cycle one, because efficiency, not effort, sets the running cost. The household that heats one room with a heat pump at 19 C is not making do with less comfort than the one running ducted gas through the whole house. It is simply paying far less for the same warm living room.
This guide is the practical household how-to. For why winter bills spike, time-of-use peak pricing and the seasonal market angle, see our companion guide on winter energy savings and tariffs.
Heating efficiency, side by side
How much heat each heater gives per unit of energy
This single column, heat delivered per unit of input energy, explains your whole winter bill. The bigger the number, the cheaper that heater is to run for the same warmth.
| Heater type | Energy source | Heat per energy unit | What it means |
|---|---|---|---|
| Reverse-cycle air conditioner (heat pump) | Electricity | 3.0 to 5.0 | Pumps existing heat indoors, so 1 kWh in becomes 3 to 5 kWh of heat |
| Ducted gas heating | Gas | 0.8 to 0.9 | Burns gas, so most of the energy becomes heat, but never more than it burns |
| Gas space heater | Gas | 0.8 to 0.9 | Similar to ducted gas per unit, heats one zone rather than the whole house |
| Electric resistive / portable heater | Electricity | 1.0 | Turns 1 kWh of electricity into 1 kWh of heat, no more |
| Wood heater | Wood | varies | Cheap if you source your own wood, efficiency depends heavily on the unit |
The blind spot
Why most winter saving tips aim at the wrong target
Search for ways to cut your winter energy use and you will get the same list every year: switch off standby, swap to LED bulbs, unplug the chargers. None of it is wrong. All of it is small.
The problem is one of scale. In an Australian winter, a large share of the household’s energy goes to heating and hot water, not to the gadgets on standby. Standby loads might be a few percent of the bill. Heating a cold house with the wrong heater can be the difference between a comfortable bill and a brutal one. Spending your effort on the small stuff while ignoring the heater is like bailing a boat with a teaspoon while leaving the plug out.
There is a second, deeper miss: most tips treat all heaters as equal and tell you to simply run yours less. But heaters are not equal. A reverse-cycle air conditioner and an electric resistive heater draw electricity at the same rate per kilowatt-hour, yet one delivers three to five times the heat for that power. Telling someone to "run the heater less" when they own an efficient unit and ignore it is advice pointed in the wrong direction entirely.
The right question is not "how do I heat less?" It is "how do I get the most heat for the least energy?" Answer that, and the practical steps fall out on their own.
How winter heating actually works
Expert analysis: efficiency, the setpoint and the heat that leaks out
A heat pump moves heat, it does not make it
A reverse-cycle air conditioner is a heat pump. It does not burn anything and it does not turn electricity into heat the way a kettle does. It uses electricity to move heat that already exists in the outside air into your room, the same trick a fridge uses in reverse. Because it moves heat rather than making it, one unit of electricity in can deliver three to five units of heat out. Engineers call that ratio the coefficient of performance (COP), and for a modern reverse-cycle unit it sits at about 3 to 5. An electric resistive heater, the glowing bar or fan heater, has a COP of about 1: every unit of electricity becomes exactly one unit of heat, no more. That single difference is why the two cost so differently to run, even though the power costs the same per kilowatt-hour.
Gas burns, so it can never beat one for one
A gas heater burns gas, turning roughly 80 to 90% of the gas energy into heat and losing the rest. So per unit of energy it puts in, it gives back a little under one unit of heat: better than nothing wasted, but it can never exceed what it burns the way a heat pump does. With gas prices high across Australia in 2026, a reverse-cycle unit drawing electricity usually delivers warmth more cheaply than gas, despite electricity costing more per unit. The heat pump’s efficiency more than makes up the price gap. Gas is measured in megajoules (MJ) and billed in MJ or gigajoules (GJ), one GJ being 1,000 MJ, which is why a gas bill looks nothing like an electricity bill at first glance.
Every degree you add makes the heater work harder
Heating is about holding a gap between inside and outside. The bigger the gap, the harder the heater works to maintain it, and the longer it runs. As a rule of thumb, each extra degree on the thermostat adds roughly 5 to 10% to that heating cycle’s energy. Push from a comfortable 20 C up to 24 C and you are not just four degrees warmer, you can be paying close to a third more to run the heater. The efficient winter band is 18 to 20 C: warm enough for a jumper-and-socks living room, low enough to keep the cycle short.
The heat you pay for leaks out through gaps
None of the efficiency above helps if the warm air escapes. Gaps around doors and windows, an unsealed chimney, the space under an external door, all let your heated air out and cold air in, so the heater never stops topping up. Sealing draughts is the cheapest upgrade in the house, often a few dollars of weather strip and a door snake. And heating only the rooms you use, called zoning, shrinks the volume you are warming and the surface area through which heat can leak. Close the doors to the spare room, the laundry and the hallway, and your heater holds temperature in the living zone with far less work.
Interactive explainer
Winter heating cost comparator
Pick a heater type and how many hours a day you run it. The comparator shows the relative running cost of each option for the same warmth, using the efficiency factors above. Figures are illustrative, not a quote.
Heater type
Hours per day:
Estimated running cost, your pick
$ / day
, delivering about kW of heat for a day. That is about $ over a winter month.
All options at this usage, cheapest first
Illustrative only. Assumes a heater delivering about 5 kW of heat, electricity at 33 c/kWh, gas costed at about 11 c per kWh of delivered heat, and self-sourced wood at about 6 c per kWh of heat. Reverse-cycle uses a COP of 4.0 (mid of the 3 to 5 range), resistive a COP of 1.0. Your real cost depends on your rates, your unit and the weather. Not a quote.
What a bad heating choice costs
How a heating habit becomes a money habit
Heating mistakes are not one-off. They repeat every cold evening for three months, so a small per-hour gap turns into a real number by spring:
They run the expensive heater and ignore the cheap one
A home with a reverse-cycle air conditioner on the wall leaves it off and drags a plug-in resistive heater from room to room, because the heat pump "is for summer". They are paying up to four times as much for the same warmth, every single hour.
They heat the whole house to warm one room
Ducted heating runs through every vent so the lounge feels right, which means the spare bedroom, the hallway and the laundry are all being warmed for nobody. Closing those zones off would cut the heated volume by half or more.
They creep the thermostat up instead of dressing for it
Feeling a draught, they nudge the setpoint from 20 C to 23 C rather than sealing the gap and adding a layer. Each degree adds roughly 5 to 10% to the cycle, so the creep quietly inflates the bill while the real cause, the draught, stays open.
They let the heat leak out as fast as they make it
An unsealed door and a gappy window frame mean the heater never stops working, because the warm air is leaving as quickly as it arrives. A few dollars of weather strip would have let the heater rest between cycles.
The insider insight
The cheapest heater is probably already on your wall
Here is the part most winter guides never say plainly. In the majority of Australian homes, the cheapest heater you can run is the reverse-cycle air conditioner you bought for summer cooling. The same box that cools the house in January is a high-efficiency heat pump in July, delivering three to five units of heat for every unit of electricity. Yet households leave it idle through winter and reach for a plug-in resistive heater or fire up ducted gas instead, paying far more for the same warmth, because they think of that unit as "the air con", not "the heater".
The non-obvious Australian truth: the most efficient heating appliance in your home is often the one you already own and already paid for. Before you buy a new heater, plug in a portable one, or run the gas, switch the wall unit to heating mode and point it at the room you are in. There is no purchase, no installation, just a setting most people never use. That one change, plus 18 to 20 C and a closed door, is the biggest winter saving available to most households, and it costs nothing to make.
The practical move is simple but rarely done: heat with the heat pump you already have, set it to the efficient band, close off the rooms you are not using, and seal the draughts so it can rest. Efficiency first, effort second.
Grounded in the analysis
What you should actually do this winter
Specific steps that follow from how winter heating works, in order of impact.
Heat with your reverse-cycle unit
If you have an air conditioner on the wall, switch it to heating mode and use it as your main heater. At a COP of 3 to 5 it is usually the cheapest warmth in the house, far cheaper than a plug-in resistive heater and, at today’s prices, cheaper than gas.
Set 18 to 20 C and leave it
Pick a temperature in the efficient band and stop nudging it up. Each extra degree adds about 5 to 10% to the running cost, so a jumper beats a higher setpoint. A timer or schedule keeps it off when the room is empty.
Heat one zone, seal the rest
Close doors to rooms nobody is using so you heat a small volume, not the whole house. Then fit weather strip and a door snake on the heated room: the heat you pay for stays where you are, and the heater rests between cycles.
Turn the hot water down a little
Hot water is the other big winter load. A slightly lower water-heater setpoint and shorter showers cut it noticeably, without a cold rinse. If your tank runs on a controlled or off-peak circuit, leave that timing alone.
Use the free heat and block the cold
Open curtains on the sunny side by day to let the sun warm the room, then close them at dusk to hold the heat in. Heavy or lined curtains over a draughty window are a cheap insulation upgrade.
Then check your plan and tariff
Once your home heats efficiently, make sure you are not overpaying for the energy itself. Compare your plan, and if you are on time-of-use, run big loads off-peak. See the tariff side of winter in our companion guide.
One state caveat that matters: the efficiency steps above work everywhere, but the last one, switching plans, depends on retail competition. Victoria, New South Wales, South Australia, Queensland and the ACT let you choose your retailer and tariff. In Western Australia (Synergy) and the Northern Territory (Power and Water) there is no retail competition, so your levers are tariff choice, timing and the efficiency moves on this page, not switching providers. For the market and tariff side, see our winter savings and tariffs guide.
Current figures, last updated 2026-06-15
Australian heating and price benchmarks for winter 2026. Sources: energy.gov.au for heating efficiency guidance, the Australian Energy Regulator (aer.gov.au) and Canstar’s rate database for usage rates. Heating efficiency and cost figures are illustrative ranges: confirm your own unit’s rating and your rates before relying on them, as both vary by model, climate and plan.
The bottom line
Why this matters this winter
With heating and hot water making up the bulk of the winter increase, the households who come out ahead are not the ones who unplug the most chargers. They are the ones who heat efficiently: the right heater, usually the reverse-cycle unit already on the wall, set to 18 to 20 C, pointed at the rooms they use, in a home with the draughts sealed. Do that and you stay just as warm for a fraction of the running cost. Then, once your home heats efficiently, make sure you are not overpaying for the energy itself, which is the tariff and market side of winter covered in our companion guide on winter savings.
Common questions
A Selectra expert answers your winter heating questions
For most homes it is a reverse-cycle air conditioner, the heat pump you may already own for summer cooling. It delivers about 3 to 5 units of heat for every unit of electricity it draws, so it beats an electric resistive heater (about 1 unit for 1) and, at current prices, usually beats gas too. Heating only the rooms you use and setting 18 to 20 C makes it cheaper still.
In most Australian homes today, yes. A reverse-cycle unit turns one unit of electricity into three to five units of heat, while gas heating turns one unit of gas into a little less than one unit of heat. With gas prices high, the heat pump usually wins on running cost per unit of warmth delivered, even though electricity costs more per unit than gas. The exception is a home with very cheap gas, an old or poorly maintained heat pump, or a very cold climate where output drops.
Set it to 18 to 20 C. That is the efficient winter band: warm enough to be comfortable, low enough to keep running costs down. Every extra degree adds roughly 5 to 10% to that heating cycle’s energy, because the heater works harder to hold a bigger gap to the cold outside. Reaching for 24 C does not just feel warmer, it can cost a third more to run than 20 C.
Yes, and it is one of the most effective moves you can make. Heating the whole house means warming rooms nobody is in. Close the doors to unused rooms and heat only the space you are living in, and your heater holds temperature with far less energy. Pair zoning with draught-sealing around doors and windows so the heat you pay for stays in the room.
It depends almost entirely on the heater type, not just the hours. A 2,000 watt resistive heater draws 2 kWh an hour, so at about 33 c/kWh that is roughly 66 cents an hour. A reverse-cycle unit producing the same warmth draws far less electricity because of its efficiency, often a quarter as much, so the same comfort can cost closer to 15 to 20 cents an hour. The comparator above shows the relative cost for the type and hours you pick.
One room, almost always. Whole-house heating spends energy on space you are not using, and the more area you heat the more heat leaks out through walls, windows and gaps. Heating a single living zone with an efficient heater, doors closed and draughts sealed, keeps the running cost down while you stay just as warm where you actually are.
