Winter Heating in South Africa: Gas vs Electricity

Why the Question Matters

When the temperature drops, many South African families wonder how to keep their homes warm without breaking the bank. The obvious guess is that electricity is the cheapest way to heat a house, but the reality is a bit more complicated.

How We Compared the Two Options

The Model Home

We imagined a typical three‑bedroom house about 150 m² in size:

• Open‑plan living/dining area: 30 m²
• Master bedroom: 13.5 m²
• Two smaller bedrooms: 9.5 m² each

Electricity Scenario

• Living/dining: 2 kW oil heater running 6 hours a day.
• Quick boost: 800 W fan heater for 1 hour in the morning and 1 hour in the evening.
• Bedrooms: 400 W panel heater on all night.
• Extra comfort: electric blankets for 2 hours before bed.

Under these assumptions the house uses roughly 714 kWh of electricity each month. At an average rate of R3.20/kWh, the monthly bill comes to about R2 285.

Gas Scenario

A three‑panel portable gas heater serves as the main heat source. We adjusted its usage to match typical winter conditions in different cities.

What the Numbers Show – City by City

Durban – Mild Winters, Big Savings

Even though Durban locals might argue, the city stays warmer inland. A 9 kg gas cylinder lasts about 13.6 days here, which means roughly 2.2 cylinders per month. At the current refill price of R365 per bottle, the heating cost is around R803 a month – about one‑third of the electricity bill.

Mbombela – Hot Days, Cold Nights

Afternoon temperatures often climb above 20 °C, but nights can plunge to 6 °C. Because of this swing, a 9 kg cylinder lasts only about 7.1 days, or 4.2 bottles per month. The monthly gas cost works out to roughly R1 533, still lower than the all‑electric estimate.

Cape Town – Wind, Rain, and Longer Heating Times

Cold fronts bring wind and rain, making homes feel chilly for extended periods. In this model a cylinder lasts about 6 days, leading to 5 bottles per month and a heating bill of around R1 825.

Bloemfontein – The Coldest Spot Tested

Nighttime temperatures regularly hit freezing, with frost common in the coldest months. A 9 kg cylinder lasts only 4.9 days, meaning 6.1 bottles per month. The monthly gas expense is about R2 227, which is still a bit cheaper than the electricity scenario.

Why Gas Can Beat Electricity

Even though a unit of electricity might look cheaper on paper, heating several rooms overnight consumes a lot of power. In our model, keeping the bedrooms warm accounted for more than 40 % of the total electricity use. Gas heaters, especially when used as a primary source, can deliver the same warmth with less overall energy, making the monthly cost lower in many cases.

Things to Keep in Mind

These numbers are illustrative, not a guarantee. Actual costs depend on:

• How well the house is insulated
• How many rooms are actually heated
• Personal habits (e.g., using only electric blankets)
• The efficiency of the heater or gas appliance
• Local weather variations

Families who heat only the rooms they occupy or rely mainly on blankets can see even lower electricity bills. Likewise, occasional gas use will need fewer cylinders than the model predicts.

Conclusion

For a typical South African three‑bedroom home, gas heating often works out cheaper than electricity during winter, especially in milder climates like Durban. While electricity remains convenient, the way we use it—particularly heating bedrooms all night—can drive up costs. Checking your own home’s insulation, heating habits, and local gas prices will help you decide which option keeps you warm and your wallet happy.