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1 WATT 1 KILOWATT = 1,000 WATTS 1 MEGAWATT = 1,000,000 WATTS 1 GIGAWATT = 1,000,000,000 WATTS flying a Boeing 747 average power use of Washington (2010) average power use of United States (1940) 140 megawatts blue whale peak metabolic output 2.5 megawatts laptop computer 15-30 watts electric train 1-2 megawatts wind turbine (2011 GE 2.5 MW) 2.5 megawatts 11 gigawatts 68 gigawatts 840 gigawatts 0.5 – 1 gigawatt Nuclear reactor 7 gigawatts Grand Coulee Dam single mini light LED / traditional 0.05 watt / 1 watt Energy is the ability to do work. A joule is a unit of energy. 1 joule of energy is used in lifting a 1 kilogram brick (2.2 pounds) 10 centimeters (3.9 inches). A kilowatt-hour is a unit of energy. Running a 1.2 kilowatt microwave for 1 hour uses 1.2 kW-h of energy. That’s 4.3 megajoules or 4,300,000 joules. Power is how fast energy is used or produced. A watt is a unit of power. A watt (W) is a joule (J) of energy used or produced per second. In 2010, the average US power use was 3.3 terawatts, or 3,300,000,000,000 watts. A horsepower is a unit of power. 1 horsepower (hp) is 745.7 watts. The average compact car has a peak power production of 150 hp. human body base metabolism 80 watts 1 kilowatt microwave 26 cu ft. refrigerator (annual average – peak) 50 – 1400 watts driving a typical car or SUV 50-130 kilowatts 1-2 kilowatts iron small solar panel array (peak production) 1.5 kilowatt ~10 m 2 space shuttle liftoff hand-cranked generator 10 watts 50 m 100 m 10+ m/s Power Basics: How much is a watt?
