What's the Difference? Kilowatt vs. Kilowatt-Hour

Do you have trouble keeping kilowatt (kW) and kilowatt-hour (kWh) straight? Put yourself in the driver's seat of our car.

You know that your speedometer measures your speed at any given moment and that your odometer measures the distance you've traveled. kW and kWh have the same relationship.

Kilowatts (1,000 watts) measure how much power is being used at a given moment. For example, a 1 kW microwave draws 1 kW of power while it's running, but no power when it's turned off. Kilowatt-hours measure the amount of power used over a given amount of time. If that 1 kW microwave runs for one hour, it will use 1 kWh of electricity.

Remember that kWh is the measure of energy use over time. A 10-watt LED bulb will never draw a kW, but it will eventually use a kWh; it will just take about 100 hours to do so.