Kilowatt-hour (kWh)
What a kilowatt-hour actually is, why your bill uses it instead of joules, and how much of it each appliance in the house gets through.
Questions people ask
How do I work out what an appliance costs to run?
Multiply its power in kilowatts by the hours it runs, then by your price per kWh. A 2 kW heater for 3 hours at 0.30 is 2 × 3 × 0.30 = 1.80.
Is a kWh the same as a unit of electricity?
Yes. Suppliers say unit and mean kilowatt-hour.
Does this page work offline?
Yes, after the first visit. The service worker caches it, so the reference stays available with no connection.
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Last updated 22 August 2026