🔌 Appliance Electricity Cost Calculator
Curious what an appliance really costs in electricity? Enter the power draw (in watts), how many hours a day it runs and your electricity price for a monthly and yearly estimate.
Cost per month
£4.50
Cost per year
£54.00
Monthly use in kWh: (100 ÷ 1000) × 5 × 30 = 15 kWh
Multiply by electricity price: 15 kWh × £0.30/kWh = £4.50
Formula
Cost = (watts ÷ 1000) × hours per day × days per month × price per kWh
Power in watts is converted to kilowatts by dividing by 1000. Multiplied by the running hours, you get consumption in kWh, which you multiply by your price per kWh for the cost.
Steps
- 1Find your appliance's power rating (usually on the nameplate or in the manual).
- 2Estimate how many hours per day the appliance runs on average.
- 3Enter your monthly electricity price (check your bill for the current rate).
Typical household appliance power
| Appliance | Power | Typical use |
|---|---|---|
| LED lamp | 9 W | 5 hours/day |
| Refrigerator | 150 W | 24 hours/day |
| Washing machine | 2000 W | 1 hour/day |
| Oven | 3000 W | 1 hour/day |
| Heat pump | 3500 W | 6 hours/day |
Values are approximate; check your appliance nameplate for exact watts.
commonMistakes
- Confusing watts and kilowatts — make sure you divide watts by 1000 to get kilowatts.
- Only accounting for peak usage; many appliances don't run at full power continuously.
- Using outdated electricity rates — check your latest bill for current prices.
useCases
- Assessing whether a more energy-efficient appliance is worth the investment.
- Determining which household appliance uses the most electricity.
- Planning for an energy-saving or sustainability project at home.