Energy Concepts & Terms

This page includes a quick orientation to common energy concepts and terms.

**Power = Energy/Time**

- Power is Energy per unit time.
- Energy is related to power as gallons are related to gallons per minute.

#### Energy and Power terms

- British Thermal Unit (Btu) - A Btu is the amount of energy required to raise the temperature of one pound of water 1 degree Fahrenheit.
- Therm = 100,000 Btu, heat energy sources such as natural gas and steam may be sold in therms.
- Kilowatt (kW) – A measure of power equal to 1,000 watts. Also equal to 3,412 Btu/hr.
- Kilowatt-hour (kWh) - A kilowatt-hour is the quantity of energy delivered when power flows at the rate of one kilowatt for one hour. It is equal to 3,412 Btu.
- Cooling Ton - A cooling ton is 12,000 Btu/hr. It is the rate of cooling required to produce one ton of ice in a 24 hour period. The capacity of most air conditioning systems are expressed in tons.