How much power does that use?
Almost everything that surprises people about their electricity bill comes down to one rule: things that make heat use hundreds of times more power than things that make light.
80% of a tumble dryer
2,000 W is more than 7 of the 12 references on this page.
Reference figures are measurements and are rounded; the unit conversion behind them is exact.
| Reference | Size | Yours ÷ theirs | Note |
|---|---|---|---|
| LED bulb | 9 W | 222× | |
| phone charger | 20 W | 100× | |
| laptop | 60 W | 33.3× | |
| resting human | 100 W | 20× | |
| fridge | 150 W | 13.3× | |
| washing machine | 700 W | 2.86× | |
| microwave | 1,000 W | 2× | |
| tumble dryer | 2,500 W | 0.8× | |
| electric oven | 2,500 W | 0.8× | |
| kettle | 3,000 W | 0.667× | |
| immersion heater | 3,000 W | 0.667× | |
| electric shower | 9,000 W | 0.222× |
Worth knowing
- An electric shower draws 9 kW — a thousand LED bulbs. It is usually the single largest load in a house.
- A human at rest radiates about 100 W, which is why a full room warms up and why old cinemas needed so much cooling.
Frequently asked
What is the difference between watts and kilowatt-hours?
Watts are the rate, kilowatt-hours are the amount. A 2 kW heater running for 30 minutes uses 1 kWh. Bills charge for kWh; appliance labels quote watts.
Which appliances cost the most to run?
Anything that heats: showers, dryers, ovens, immersion heaters. Electronics are almost irrelevant by comparison, however much they are left on.