“Wh” stands for watt-hour, which is a unit of energy. The watt-hour measures the amount of energy used or produced over time.
Here’s a closer look at the Wh:
Definition:
- A watt-hour represents the amount of energy consumed when a device that uses power at a rate of one watt operates for one hour.
Relation to Other Units:
- 1 kilowatt-hour (kWh) = 1,000 watt-hours (Wh)
- 1 megawatt-hour (MWh) = 1,000,000 Wh
- 1 gigawatt-hour (GWh) = 1,000,000,000 Wh
- 1 terawatt-hour (TWh) = 1,000,000,000,000 Wh
Practical Examples:
- If you have a 60-watt light bulb and you leave it on for one hour, it will consume 60 watt-hours of energy.
- A laptop that uses 50 watts of power running for 2 hours will consume 100 Wh.
Usage in Electricity Billing:
- Energy consumption in homes and businesses is typically billed in kilowatt-hours (kWh), which is a larger unit than the watt-hour. A kWh represents the energy consumed when a device rated at 1 kW runs for one hour.
Energy Storage:
- Battery capacity is often rated in watt-hours or its multiples (like milliwatt-hours or kilowatt-hours). This rating indicates the total amount of energy the battery can store and provide. For example, a laptop battery might have a capacity of 50 Wh, meaning it can theoretically supply 50 watts for one hour before it’s exhausted.
In summary, a watt-hour (Wh) is a measure of energy that indicates the amount of electricity consumed or stored over time. It’s a fundamental unit used in various applications, from electricity billing to rating the energy storage capacity of batteries.