kilowatt
/ˈkɪləwɒt/ noun- A unit of power equal to one thousand watts.
- The word most often confused with kilowatt-hour.
12 August 2026 · Berlin · 1 minute
Power is a rate; energy is an amount. A kilowatt says how fast; a kilowatt-hour says how much. The difference is the difference between the width of a pipe and the water in a bath.
1
The arithmetic
The relation is one line:
(1)
A charger of kW running for hours delivers kWh, if the car can take it all that time. It usually cannot: the battery slows the charge as it fills.
Table 1
Real cars taper. The figures are rounded.
Real cars taper. The figures are rounded.
| Charger | Power | 10–80% in a 60 kWh battery |
|---|---|---|
| Home socket | 2.3 kW | 18 hours |
| Wall box | 11 kW | 4 hours |
| Fast charger | 50 kW | 55 minutes |
| Ultra-fast | 150 kW | 25 minutes |
2
Why it matters
When a driver asks how long will it take, the answer needs both units and the battery between them. Saying 150 kW answers a question nobody asked. Saying twenty-five minutes answers the one they did.