Free planning tool
Electricity cost calculator
Estimate electricity use from input power, operating hours and your tariff. For a heat pump, use electrical input or measured consumption, not its heating-output rating.
How the result is worked out
Energy (kWh) = watts ÷ 1,000 × hours per day × days × average load fraction. Cost = energy × electricity price per kWh. The load fraction is your assumption about average draw while operating.
What to keep in mind
Calculates one device or one combined electrical load. Excludes standing charges, time-of-use changes and other devices. It does not size a heating system or predict a whole home's seasonal demand.
Read the related guide: How to estimate a cabin’s electricity use and running cost →