Glossary

Watt-hour (Wh)

- Measure of electrical power in time. One watt-hour of electricity is equal to one watt of power consumed over one hour. A 10-watt light bulb uses 10 watt-hours of electricity in one hour (see also kWh).

Watt (W)

- Unit that measures the rate of energy, calculated by multiplying volts by amps.