When the cold really hits in winter, you need to find a middle ground between having a home that's cosy and a resulting energy bill that won't send you broke. This guide will help you heat your home using less power but with maximum effectiveness.
The main types of heaters include electric heaters, gas heaters and reverse-cycle air conditioners. The best option for you depends on a few factors. Let's take a look at each type.
These are usually portable, cheaper to buy, and a good option if you're not using them in large spaces or for long periods. Check our electric heater buying guide for more details, and also take a look at our electric fireplace heater buying guide.
- Good for: heating small spaces, or individual people.
- Read our electric heater reviews to find which models we recommend.
A gas heater can be very efficient and good value for money, and some people prefer the feel of gas heating over electric heaters and air conditioners. Gas heaters can run from reticulated natural gas (gas connected to your home) or bottled LPG, but you need to make sure you have the right model for the type of gas you have available, as a heater designed for natural gas won't work with LPG, and vice versa.
Gas heating produces small amounts of waste products: these include carbon monoxide, which is dangerous, and water vapour, which can lead to condensation and mould problems. They also release nitrous dioxide and fine particles, which several studies have shown are a factor contributing to childhood asthma and other respiratory health problems. Flued gas heaters and central ducted gas heating may be less likely to have this risk as they vent most of the waste outside, but they can still release a small amount of emissions into the indoor air, so the risk is not zero for these types either.
- Flued heaters direct their fumes outside through a flue, or pipe, and are generally more expensive to buy and install. This removes the waste products such as carbon monoxide and water vapour from the home, which is safer, but can also create a small amount of heat loss, reducing the efficiency.
- Portable, or unflued heaters expel their waste products into the room being heated. Australian standards and regulations strictly limit the amount of emissions allowed, but even so you need to keep the room ventilated.
- Gas heaters need to be professionally serviced every few years to ensure they're operating safely and effectively.
- NEVER use an outdoor gas heater for indoor heating! They don't have the same emission standards as indoor gas heaters and can give off a dangerous amount of carbon monoxide and other gases if left running indoors for several hours. The same applies for your kitchen's gas cooktop or oven.
- If you have a gas heater of any type (whether flued, portable unflued, or ducted central heating) then make sure to install a carbon monoxide alarm too – they're readily available from hardware stores. This could save your life if the heater develops a fault and starts putting out dangerous amounts of this deadly gas.
- Check our gas heater buying guide for more details.
If you're going to leave a heater on all day, a gas heater may be cheaper to run than a portable electric heater, though probably not as cheap as a reverse-cycle air conditioner. However, average national gas prices have risen in recent years and solar power is making electricity much cheaper in many homes. It's not a given that gas heating is always cheaper than using electricity; see the heating cost comparisons below. Gas is a fossil fuel, a factor to consider if you're trying to go green.
- Good for: heating smaller to medium-sized spaces.
- See our gas heater reviews if you're ready to buy.
Reverse-cycle air conditioners
These are very effective for heating individual rooms and large spaces such as an open-plan living area. And they're much more economical than trying to heat the same space with portable electric heaters, because for every unit of electricity they consume, they can put out three or more units of heat, due to the heat pump technology they use. The downside of a reverse-cycle air conditioner is that it's more expensive to buy and install than a portable electric heater. Check our air conditioner buying guide for more details.
- Good for: small models are good for a single room, while larger models can heat bigger spaces such as open-plan living areas.
- We rate small, medium and large units in our reverse-cycle air conditioner reviews.
The costs below are based on using the heater in a moderate climate, for six hours a day over 12 weeks in winter. They're indicative costs only; your costs will depend on your home, your local climate and the prices you pay for electricity and gas. For example, for a home with its own solar panel system, running an electric heater or air conditioner in daytime can be significantly cheaper than running a gas heater.
|Suitable heater type||Running cost / 500 hours|
|Small gas (1.5kW)||
|Portable electric heater (2.4kW)||
|Small reverse-cycle air con (3.5kW)||
|Suitable heater type||Running cost / 500 hours|
|Medium gas (3.5kW)||
|Medium reverse-cycle air con (6.0kW)||
|Suitable heater type||Running cost / 500 hours|
|Large gas (7kW)||
|Large reverse-cycle air con (8.5kW)||
Before buying a heater
Make your home as thermally efficient as you can to keep the heat inside in winter and outside in summer.
- Eliminate draughts. Make sure windows and doors are well sealed. Use draught excluders and door snakes if needed and close off any rooms you don't need to heat. But remember that if you're using a portable gas heater, you need some ventilation.
- Insulate the ceiling. Ideally, walls and floors should also be insulated. Rugs can provide some useful insulation on a hard floor.
- Curtains and blinds will help keep the warmth from escaping through glass windows and doors.
Before the winter chill hits, think about what sort of heating you're going to need.
- If you know you're going to need a new electric or gas heater, try to beat the rush and buy one ahead of winter (which is not always easy, as stores often don't stock many heaters until the cold weather arrives). Look online for cheap second-hand models, but these might need a service to ensure they work safely. Alternatively, pick one up cheap in a clearance sale after winter and store it for next year.
- Clean your reverse-cycle air conditioner's filters to keep it running effectively, and consider whether it needs a service.
- If you're looking at having a new air conditioner or flued gas heater installed, get this done well ahead of the peak cold season; don't wait until the installers are busy. You might pick up an off-season bargain this way.
The right sized heater
Make sure you get the right size of heater for the space you're looking to heat – see above for our size tips for each heater type.
- Room heating calculators can be found online; try searching for room heater size.
- There are several factors to consider when choosing your heater's capacity: the climate you live in, the floor area and ceiling height of the room, how much natural sunlight it receives, whether the room is carpeted, whether adjacent rooms or floors above and below are heated, and of course the amount of other insulation.
As a general guide: for moderate climates, a well-insulated room of 20 square metres will probably need a 2000W electric heater or a gas heater with 6–8MJ input. The same room would need more heating if poorly insulated; even a 2400W electric heater could struggle, and you could need at least a 10–12MJ gas heater. In cold climates, you'll need more heating power still.
How to keep it cheap
- Only use the heater when you really need to. That sounds obvious, but it's easy to get into the habit of routinely switching the heater on when maybe just putting on a jumper is a better option.
- Don't heat rooms to tropical temperatures; for example, try 20 degrees instead of 23 degrees. Each degree less will save about 10% on your energy use.
- Only heat the rooms you're actually using.
- Hot air rises to the ceiling, so if you have a ceiling fan with a reverse-direction option, consider using it at a low speed to help circulate the hot air more evenly through the room without creating a downward breeze.
Wood-burning stoves and fireplaces
Wood fires can give a cosy look and feel to a room on a cold night. Modern slow-combustion wood-burning stoves can be quite efficient too.
Firewood should be well seasoned (left to dry for at least two summers) so you don't waste energy evaporating water by burning green wood. Hardwood contains more energy than softwood, and burns longer and more steadily. But it's also harder to light. Softwood can spit and spark in open fires.
- Wood is available almost everywhere.
- Wood heating can be very economical if you have cheap or even free firewood (however, check whether you need a permit to collect firewood from forests).
- If firewood is produced sustainably (by regrowing the amount that's used) and burned in a slow-combustion heater, it produces the least amount of CO2 of all the fuels in our comparison.
- You need somewhere to store wood in reasonable quantity.
If you're buying your firewood, it can cost several hundred dollars (or more) for a winter's worth of good firewood.
You have to load the heater or grate, start and maintain the fire and dispose of the ash.
- Apart from modern slow-combustion heaters, solid-fuel heaters are less energy-efficient than electric and gas heating.
- They produce combustion gases and need a flue or chimney, which makes installation expensive.
- Not all the smoke and other combustion products go up the chimney; some will get into the indoor air and can be a serious irritant for people with asthma and other respiratory conditions.
- The smoke from wood fires can be a major contributor to outdoor air pollution.
These use denatured ethanol (methylated spirits) which doesn't give off dangerous fumes such as carbon monoxide when burned (though it does give off water vapour and carbon dioxide). So these burners don't need vents or flues, or a gas or electrical connection.
They're comparable in heating capacity and efficiency to an unflued gas heater, and typically cost a few hundred dollars. However, they're more expensive to run – one litre of fuel, costing about $6, will give roughly 90 minutes to two hours burning on a high setting. The same amount of heating with gas would cost around 50c.
Decorative alcohol-fuelled burners were temporarily banned years ago following a long list of serious burn injuries and fire incidents, but they can now be sold as long as they meet the specified decorative alcohol-fuelled device safety standard. Under this standard, table top burners (devices weighing less than 8kg or with a footprint less than 900cm2) are not allowed. Freestanding and fixed devices must pass a stability test, have a flame arrester or automatic fuel pump system and be labelled with warnings about refuelling hazards.
Many models have open flames, so you need to take the same care around them as with an open wood fireplace, and you also need to be careful when handling the fuel. A number of people have been burned by them through mishandling, hence the ban and safety standard mentioned above.
Whole house heating
Hydronic heating works through heating water (or steam), piping it through the house into panel radiators and returning the water back to the heating system to be reheated for the cycle to repeat. You can also utilise this method to provide heating to in-floor systems.
The advantages: direct control of how much heat you want to each room via the system's panel radiators, which are quiet and unobtrusive. It's a relatively quick way of heating, low maintenance and it's well tested, having been used in many countries for around a century.
The disadvantage is it's quite expensive to install; quotes can start at around $6000.
The heating supply is usually a boiler, fuelled by natural gas, LPG, electricity, or solid fuel. Look for a low content boiler so it's not wasting fuel, panels that heat up quickly and can be controlled independently, and pipes that don't lose heat where they don't need to.
Ducted reverse-cycle air conditioning
Ducted air conditioners consist of a compressor (which can be installed outside or in the ceiling space, for example) and ducted outlets in the rooms you want to heat or cool. A good system can be very efficient, but installation can be costly, in the several thousands of dollars. Consider it if you're building or renovating a house.
For this type of heating, electric wiring or water pipes are installed into the concrete floor slab. The slab is heated, using cheap off-peak electricity or hot water (in which case you can use a gas heater to heat the water if gas is available). It then releases the stored heat during the day, in a similar way to an off-peak storage heater. The substantial construction work required for this type of heating means it's more appropriately installed when a house is being built.
Ducted gas central heating
This system consists of a gas furnace (which can be installed outside or underfloor) and ducting vents in the rooms you want to heat. A ducted system may work out cheaper to run than two gas space heaters, though installation costs are usually much higher.
Typically a slow-combustion stove with heat shifters: the stove in one room is connected to a system of ducts and fans in the ceiling space that shift warm air to other rooms. This could be a good option if you have a large supply of cheap wood or other solid fuel, but the same negatives listed above for any wood-burning stove still apply.