1 WATT

1 KILOWATT = 1,000 WATTS

1 MEGAWATT = 1,000,000 WATTS

1 GIGAWATT = 1,000,000,000 WATTS

�ying a Boeing 747

average power use of Washington (2010)

average power use of United States (1940)

140 megawatts

blue whalepeak 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 gigawatts0.5 – 1 gigawattNuclear reactor

7 gigawattsGrand Coulee Dam

single mini lightLED / 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 kilowatts1-2 kilowatts

ironsmall solar panel array

(peak production)

1.5 kilowatt

~10 m2

space shuttle lifto�

hand-cranked generator10 watts

50 m

100 m

10+ m/s

Power Basics: How much is a watt?