// LAB 11 · INTERACTIVE
Electricity bill calculator: kWh per appliance
Add your appliances, hours and price per kWh — see what each one really costs per month.
⚡ POWERING UP THE LAB…
// HOW IT WORKS
The idea in 30 seconds
- kWh = watts × hours ÷ 1,000. One kWh is "1 unit" on your bill.
- A 1,500 W air conditioner for 6 hours = 9 kWh a day — about as much as a 9 W LED bulb uses in 2.7 years of 1 hour a day.
- Anything that heats or cools uses the most. Phones, routers and LED bulbs are tiny by comparison.
- Watts here are typical; the real number is on the label of your appliance.
Watch the lessons
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