How much does heating cost by fuel type?
Compare gas, heating oil, wood pellets and electricity per useful kWh: Ofgem cap, NEP fuel prices and boiler efficiency. Calculator for your heat demand.
- Cost per useful kWh
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- Fuel energy used
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Comparison at the same heat demand
- Electricity (heaters)
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- Mains gas
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- Kerosene (heating oil)
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- Wood pellets (bagged)
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Defaults: electricity Ofgem Direct Debit average 26.32p/kWh (1 Oct–31 Dec 2026); gas Ofgem 7.97p/kWh + £108.33/yr standing (29.68p/day); kerosene and bagged pellets from Nottingham Energy Partnership October 2026, converted to £/kWh of fuel. Efficiencies 90% for boilers/stoves, 100% for electric heaters — editable. Electricity standing charge omitted. Results are indicative estimates based on the values you enter. Always check your appliance labels, your tariff and the manufacturer’s data.
- Under the Ofgem price cap (1 Oct–31 Dec 2026, Direct Debit averages), gas is 7.97p/kWh plus 29.68p/day standing; electricity is 26.32p/kWh.
- Kerosene averaged 120.99p/litre in the Nottingham Energy Partnership October 2026 comparison (about 12.4p per kWh of fuel before boiler losses).
- Bagged wood pellets averaged 44.30p/kg in the same NEP table (about 9.2p per kWh of fuel).
- At equal useful heat, pellets and gas beat oil and resistive electric heating; a heat pump changes the electric picture.
Enter your useful heat demand (the heat actually delivered to the home), then pick a fuel to edit its unit price, standing charge and efficiency. The results panel compares all four options at the same demand.
Why “useful kWh” matters
A litre of oil, a billed unit of gas and a kilowatt-hour of electricity are not the same thing once boiler or stove losses are counted. The calculator turns each tariff into a cost per useful kWh of heat: fuel price ÷ efficiency.
Default efficiencies (editable): 100% for resistive electric heaters, 90% for a modern gas or oil boiler and for a well-run pellet boiler or stove. An old 70–80% boiler costs more for the same warmth.
Price defaults (autumn 2026)
| Fuel | Default unit price | Standing | Source | Period |
|---|---|---|---|---|
| Electricity | 26.32p/kWh | £0 (omitted) | Ofgem Direct Debit average | 1 Oct–31 Dec 2026 |
| Mains gas | 7.97p/kWh | £108.33/yr (29.68p/day) | Ofgem Direct Debit average | 1 Oct–31 Dec 2026 |
| Kerosene | 12.37p/kWh of fuel (from 120.99p/litre ÷ 9.78 kWh/litre) | £0 | Nottingham Energy Partnership | October 2026 |
| Bagged pellets | 9.23p/kWh of fuel (from 44.30p/kg ÷ 4.80 kWh/kg) | £0 | Nottingham Energy Partnership | October 2026 |
NEP’s published “price per kWh including boiler efficiency” already folds in 90% efficiency; we store the fuel price and apply efficiency in the tool so you can change either. Electricity standing charge is left at zero because most homes already pay it for lights and appliances; add it back if you are comparing an all-electric heating system in isolation.
Ballpark for 12,500 kWh of useful heat
With the calculator defaults:
| Fuel | Fuel energy used | Estimated annual cost |
|---|---|---|
| Bagged pellets (90%) | ≈ 13,900 kWh | ≈ £1,280 |
| Mains gas (90% + standing) | ≈ 13,900 kWh | ≈ £1,220 |
| Kerosene (90%) | ≈ 13,900 kWh | ≈ £1,720 |
| Electricity (100%) | 12,500 kWh | ≈ £3,290 |
Gas and pellets are in a similar band once standing charges are included; oil is higher after the 2026 price rise in NEP’s table; resistive electric heating is far more expensive for whole-home heat. A heat pump can bring the electric cost back down by delivering several kWh of heat per kWh drawn from the grid.
How to estimate your heat demand
- Gas or oil bill: take annual kWh (or litres × about 9.8 kWh/litre for kerosene) and multiply by your boiler’s real efficiency if you know it.
- All-electric home: the heating share of your bill is close to useful heat, because resistive heaters are roughly 100% efficient at the point of use.
- Rule of thumb: NEP’s comparison uses about 12,500 kWh of annual heat for a medium home; a well-insulated flat needs much less.
To put the rest of your electricity use in context, see average household electricity usage and space heater running costs.