Can you explain electric and natural gas measurements?

Kilowatt ( kW), Megawatt (MW), and Gigawatt (GW) are used to express power generating capacity or customer demand. Demand is how much electricity is needed at any given time to fully meet a customer or customers needs. For example, a residential customer in winter during the middle of the night may not have a very high demand because not many electrical devices are running, but demand may be high in summer during the heat of the day when air conditioners and machinery are used. Likewise, the electricity a utility must have available on its system to meet its entire customer demand varies hour to hour and season to season.

Watt – named after the Scottish inventor James Watt (1736 – 1819). A Watt is the basic unit of energy produced by one ampere of current flowing under one volt of potential at a power factor of 100 percent. Most appliances are rated by the amount of electric power they consume in Watts

Kilowatt (kW)– 1,000 Watts

Megawatt (MW) – 1 million Watts

Gigawatt (GW) – 1 billion Watts

Kilowatt-hour (kWh) – A measurement of how much electricity a customer uses in an hour. The system-wide average use for a residential customer is 500 kWhs a month.

Therm – An amount of thermal energy equal to 100,000 British thermal units (Btu). A Btu is the amount of energy required to heat one pound of water by one degree Fahrenheit at sea level. Natural gas is measured by the amount of energy contained in the gas delivered/used. The energy available in natural gas may vary depending on the source. For example, although methane makes up most of the gas, one supplier may also have significant amounts of butane and propane while another supplier has nitrogen in the gas and each gas has a different heating value. Natural gas is metered based on volume and is adjusted based on meter calibration, delivery pressure, and altitude. Then an adjustment is made to reflect the heating value of the gas. The system-wide average use for a residential customer is 60 therms a month.

Decatherm (Dth) – 10 therms