What is the difference between kW and kWh?

It's easy to mix up kW and kWh. Don't worry, we all do it! Here is Zaptec's handy explainer.


kWh "Kilowatt -hour"

This is a measure of energy. It’s an amount, like gallons or litres.


The energy you use to charge up your battery is measured in kWh of electricity - in the same way you’d measure the filling up of a normal car with “litres of petrol or diesel”.

You usually pay for electricity per kWh. More kWh = you can drive further


kW - Kilowatt

This is a measure of power. It’s a rate or speed, like miles per hour or kilometres per hour.


This is the speed of charging, or charging rate. It’s a measure of how fast the energy in your battery will increase. Some chargers are fast, some are slow and the speed is measured in kW.

Batteries take time to charge, so it’s an important measure.

More kW = you can charge faster 

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