The electricity sector generally uses the unit "kilowatt" (1,000 watts) or multiples thereof, such as megawatt (MW, i.e. 1,000,000 watts) as its standard measure of power.

The sector also uses the unit kWh for energy, which is different from the scientific units of newton–meters or joules. The kWh unit is the product of the rate at which energy is consumed or produced (power) and the duration or time period of consumption. If an appliance draws power at a rate of 1 kW (kilowatt) for one hour then the energy consumption over this period is 1 kWh (kilowatt-hour). A kilowatt hour can be confirmed as an energy measure by breaking it down into it basic units:

1 kWh | = | 1 kW x 1 hour |

= | (1000 joules/second) x 60 minutes x 60 seconds/minute | |

= | (1,000 joules/second) x 3,600 seconds | |

= | 3,600,000 joules or 3.6 MJ |

Industry specific units of energy are not unusual. Coal was once used extensively as a local heat source to create steam which was used drive steam engines, presses and other devices. The emphasis was on using measures related to heating water. The energy unit in common use was the BTU or British Thermal Unit. A BTU is approximately the amount of energy needed to heat 1 pound (0.454 kg) of water from 39 to 40 ° F (3.8 to 4.4° C). This unit of heat is still in common use in the United States and a number of other countries. In Australia, you may still see a gas appliance with a BTU rating on its nameplate.