Electricity, Energy Quantities, and Power Units

Electricity is one form of energy. Energy has other forms such as work, light, and heat. Scientists use a few different terms to describe energy and their different forms.

The British Thermal Unit (BTU) is a unit of energy production or heat value. BTUs are used to describe the potential power from the use of coal, oil, and natural gas for generating electricity, providing heat, and providing fuel for transportation. The higher the BTU value of a fuel, the more efficient it is. When we talk about heating and cooling appliances, a higher BTU value refers to more heating or cooling from an appliance.

1.0 BTU = 1055 Joules

Recall that electrical power is measured in watts (W). A Joule is a measure of energy that corresponds directly to a Watt.

1 W = 1Joule
          Second

1000 W = 1 kilowatt

Energy delivered by electric utilities is usually expressed in kilowatt-hours (kWh).

1.0 kilowatt-hour (kWh) = 3,600,000 Joules = 3413 BTU