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Electric Heating · Ofgem 1 July to 30 September 2026

3 kW Convector Heater running cost — 6 h daytime (home-worker)

A 3 kW Convector Heater (3,000 W) running 6 hours/day uses 18.00 kWh and costs £4.70/day at the Ofgem cap of 26.11p/kWh (1 July to 30 September 2026).

3 kW Convector Heater6 h daytime (home-worker): 3,000 W ÷ 1000 × 6 h × 26.11p/kWh = £4.70/day. Weekly (5 days): £23.50. Annual: £1221.95. Coverage: Large living room or open-plan space (~30 m²). Source: Energy Saving Trust (wattage, typical/indicative); Ofgem (OGL v3.0).

Per hour
78.3p
Per day (6 h)
£4.70
Per week (5 days)
£23.50
Per year
£1221.95

Heater specification

Rated power
3,000 W (3.0 kWh/h)
Coverage
Large living room or open-plan space (~30 m²)
Cost per kWh (Ofgem cap)
26.11p
Cost per hour
78.3p

Energy Saving Trust — typical 3 kW convector heater rating

How the cost is worked out

  1. Wattage: 3 kW Convector Heater draws 3,000 W = 3.0 kWh per hour.
  2. Daily use: 3.0 kWh × 6 h = 18.00 kWh/day.
  3. Daily cost: 18.00 kWh × 26.11p = £4.70.
  4. Weekly (5 days): £4.70 × 5 = £23.50.
  5. Annual: £23.50 × 52 = £1221.95.

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Updated each time the Ofgem cap changes.

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3,000 W wattage from Energy Saving Trust — Heating your home guide (typical appliance ratings) (typical/indicative). Unit rate 26.11p/kWh from Ofgem — Energy price cap unit rates and standing charges (1 July to 30 September 2026), OGL v3.0.