ENERGY UNITS OF MEASUREMENT SYMBOL UNIT OF ENERGY EQUIVALENT CONSUMPTION AMOUNT EQUIVALENT TO 1TWh kWh kilowatt-hour 1 kWh = Ten 100-watt light bulbs on for 1 hour 1,000,000,000 kWhs MWh megawatt-hour 1 MWh = Avg. U.S. household for 1 month 1,000,000 MWhs GWh gigawatt-hour 1 GWh 100 avg. U.S. households for 1 year 1,000 GWhs = ˜ TWh terawatt-hour 1 TWh 100,000 avg. U.S. households for 1 year 1 TWhs = ˜ 48