A kilowatt-hour is one kilowatt of power being used for one hour. It is the amount of energy needed by a 40-watt light bulb being left on for 25 hours.
We also call it a ‘unit’ of energy.
Here are some rough examples of 1 kWh:
- Using a 10,000 watt electric shower for six minutes
- Keeping an immersion heater (3,000 watts) on for 20 minutes
- Cooking in a 2,000 watt oven for half an hour
- An hour’s ironing with a 1,000 watt iron or 45 minutes with a 1,500 watt iron
- Less than an hour using a dishwasher (1,000 - 1,500 watts)
- Around three hours watching a plasma TV (280 - 450 watts)
- Keeping a fridge-freezer (200 - 400 watts) on for about three hours
- Keeping an electric blanket (130 - 200 watts) on all night
- Using a laptop (20 - 50 watts) all day
- Keeping a broadband router (7 - 10 watts) on for five days