Here are the cheapest heaters to run this winter

When temperatures drop, a warm and cosy room can take away the winter chill and cheer your spirits, but there’s a cost. We crunched the numbers and worked out how much it will cost you to run electric, paraffin and gas heaters this winter.

The cost of running electric heaters

If you’ve got electricity, and Eskom isn’t loadshedding, electric heaters are one of the easiest ways to heat up your home. You buy a heater, plug it in and the room warms up. It’s also a safe option as long as the heaters are used correctly. There are two costs you need to be prepared for when buying and using an electric heater – the cost of the heater and the cost of electricity.

Electricity is charged by the number of kilowatts (kW) used per hour. One kilowatt is 1 000 watts. On the packaging and labelling of your heater you will find the watts the heater uses, for example 1 500 W.

When you know the wattage your heater uses, multiply it by the cost of electricity and the time you use the heater for.

We used 282.37 cents per kilowatt, including VAT, which is Eskom’s Homepower Block 1 rate. Click here for  Eskom tariffs, or ask your municipality for their rates.

Here is an example of how we worked out the cost of a wall heater, working out the watts first and then the cost for three hours a day for 30 days:

Kilowatts used: divide watts by 1 000

400 ÷ 1 000 = 0.400

Cost for three hours a day for 30 days: Multiply kW x cost per kW x hours x days

0.400 x 282.37 x 3 x 30 = 10 165c or R101.65

It is important to note:

• The more watts your heater uses, the higher the electricity cost.
• Higher or warmer settings on heaters usually use more watts. Turning your heater up may give you more warmth but it could double your costs.
• The more hours your heater is on the more watts it uses, and the more you will pay for electricity.
• Low wattage heaters cost less to run, but may not warm up the room as much as you would like.
• Remember, warm winter blankets and hot water bottles do a good job of keeping you warm. Use these more and heaters less to save electricity.

Heater type	Cost	Watts used	Cost to run for three hours a day for 30 days
Wall panel heaters These can be wall mounted and some models can be painted to match the wall.	R600	400 W	R101.65
Nanotech plug in heater These are small heating units that plug into your wall socket.	R430	500 W	R127.07
Under carpet heating mats (1.75m x 2.5m) These mats are plugged into a wall and lie under your floor rugs. They warm the rug, similar to how an electric blanket warms your bed. Various sizes are available.	R3 978	700 W	R177.89
Underfloor heating This is a heating system installed under your floors, carpets, tiles, wood and laminate floors. Unlike heating mats, the system is a permanent installation operated at the thermostat unit.	R4 109 for 5.6 - 11m2 of tiled floor. R827+ for a thermostat.	940 W	R238.88
Seven-fin oil heater These run on electricity that heats the oil in the fins.	R749	1 500 W	R381.19
Infrared heater These heaters use electromagnetic radiation to transfer heat from their unit to objects in the room – much like the sun heats the earth.	R1 995	1 500 W	R381.19
Three-bar electric heater	R329	1 500 W	R381.19
Fan heater	R249	2 000 W	R508.27

Based on the above, wall panel heaters should have the lowest running costs. These heaters are suitable for heating rooms of 10 - 12m². They are easy to install as all you have to do is mount them on a wall. However, they use a low wattage so the heat they provide will be less than a gas heater or fin heater. And they aren’t portable.

We also investigated air conditioners, which came in at a monthly running cost of R889, much more expensive than other options, and the cost per unit is over R10 000!

Gas heaters

The most common gas heaters used in South Africa are the 3 panel heaters that use a 9kg canister of LPG, liquid petroleum gas. A gas heater costs around R1 200 and a 9kg gas cylinder R900 (excluding gas).

The price of gas is set by the Department of Energy and just like petrol, the price fluctuates each month. You can find the latest prices on the department’s website. You can also get quotes from gas suppliers. We priced a refill of a 9kg gas cylinder at R320 on 6 May 2024. You may also need to take your gas cylinder to be refilled so there may be some transport costs and time involved.

According to Gas Installers, a 9kg canister of gas lasts around 30 hours if you heat all three panels on your heater. This puts the cost of gas for your heater, running for three hours a day for 30 days at R960. Gas heaters are very efficient at heating rooms, and because they give a lot of heat, you may not need to run them at full power all the time. You can lower your cost by running one or two panels on the heater.

Paraffin heaters

Paraffin heaters can heat rooms very effectively. We found paraffin heaters starting at R1 300.

Like gas, the cost of illuminating paraffin is set by the Department of Energy every month. Five litres of paraffin will cost around R100 (at 6 May 2024).

Running a paraffin heater is cheap, but there are safety risks. Never leave a paraffin heater on if you are not in the room. Place the heater far away from any flammables and have a fire extinguisher or blanket nearby to extinguish any flames should the heater topple over.

Gas and wood fireplaces

These are great at heating up a room, and fireplaces using wood can be cheap to run as firewood is fairly inexpensive (R400 for 100kg of firewood). The initial price of the unit, however, can be quite expensive. We priced open wood fireplaces from R5 800, and then there is a fairly substantial cost to have them installed.

Gas and wood fireplaces need to be installed by an expert, for safety reasons. And, as with any fireplace, follow precautions that include not leaving children alone in front of the fire. Fireplaces are also not portable, so will only heat up the room and adjacent rooms where they have been installed.

The bottom line

Comparing gas and electric heaters, a wall panel heater using electricity is the cheapest heater to run.

Consider your needs, your room, your budget and your energy costs when deciding which heater to buy. The right choice will mean you’re warm and cosy and safe, without blowing your budget.

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