Whole Farm > Weight & Measurements

Updated October, 2008
File C6-86

Energy Measurements and Conversions

Deka = ten
Hecto = hundred
Kilo = thousand
Mega = million
Giga = billion
Tera = trillion

1 metric ton = 2204.62 pounds
1 metric ton = 1.1023 short tons
1 kiloliter = 6.2898 barrels (petroleum)
1 kiloliter = 1 cubic meter

British thermal unit (Btu) measurements and conversions

Approximate definition: A British thermal unit is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.

1 British thermal unit (Btu) = 252 International Table calories
1 calorie = .00397 Btus
1 Btu = .252 kilocalories (kcal)
1 kilocalorie (kcal) = 3.968 British thermal units (Btu)
1 Btu = 1,055 joules
1 Btu = 1.055 kilojoules
1 kilojoule = .947817 Btus
1 therm = 100,000 Btus 
1 dekatherm = 10 therms
1 dekatherm = 1,000,000 Btus
1 kilowatt hour of electricity = 3,412 Btu
1 horsepower = 2,545 Btu per hour

Convertit
Energy Information Administration
Energy and Work Conversion – Unit Converter
BP Conversion Factors

Joule measurements and conversions

Approximate Definition: the energy required to lift a small apple (102g) one meter against Earth’s gravity (Wikipedia).

1 joule = .0009478 Btus
1 Btu = 1,055.05585 joules
1 kilojoule = 1,000 joules
1 kilojoule = .947817 Btus
1 Btu = 1.055 kilojoules
1 kilojoule = .239 kilocalories
1 kilocalorie (kcal) = 4.187 kilojourles (kJ)
1 watt hour = 3,600 joules
1 kilowatt hour = 3.6 megajoules
1 megajoule = 1 million joules
1 terajoule = 1 million megajoules

Online conversions
Convertit.com
Energy and Work Conversion – Unit Converter
BP Conversion Factors

Electricity measurements and conversions

Approximate definition: A human climbing a flight of stairs is doing work at the rate of about 200 watts (Wikipedia).

1 watt = 1 joule per second
1 watt = 3.412 Btu per hour
1 Btu per hour = .293 watts
1 kilowatt (kW) = 1,000 watts
1 kilowatt = 3,412 Btu per hour
1 kilowatt = 1.341 horsepower
1 horsepower = .746 kilowatts
1 megawatt (MW) = 1 million watts
1 gigawatt (GW) = 1 billion watts
1 terawatt (TW) = 1 trillion watts
1 gigawatt = 1 million kilowatts

Watt hours
Approximate definition: One watt-hour is the amount of (usually electrical) energy expended by a one-watt load (e.g., light bulb) drawing power for one hour (Wikipedia).

1 watt second = 1 joule
1 watt minute = 60 joules
1 watt hour (Wh) = 3,600 joules
1 watt hour = 3.6 kilojoules
1 kilowatt hour (kWh) = 3.6 megajoules
1 megajoule = .278 kilowatt hours
1 kilowatt hour = 3,412 Btus
1 kilowatt hour = 860 kilocalories
1 kilowatt hour = 3,600 kilojoules (kJ)
1 kilowatt hour = 1.34 horsepower hours
1 horsepower hour = .746 kilowatt hours
1 kilowatt hour = 1 thousand watt hours
1 megawatt hour (MWh) = 1 million watt hours
1 gigawatt hour (GWh) = 1 billion watt hours
1 terawatt hour (TWh) = 1 trillion watt hours
1 gigawatt hour = 1 million kilowatt hours
1 terawatt hour = 1 billion kilowatt hours
1 terawatt hour = 1 million megawatt hours

Online conversions
Convertit.com
Energy and Work Conversion – Unit Converter
BP Conversion Factors

Power measurements and conversions

1 Btu per second = 1.055 kilowatts
1 Btu per second = 1.415 horsepower
1 Btu per second = 1.434 metric horsepower
1 Btu per second = .252 kilocalories per second
1 kilowatt = .9478 Btu per second
1 kilowatt = 1.341 horsepower
1 kilowatt = 1.36 metric horsepower
1 kilowatt = .2388 kilocalories per second
1 horsepower = .7457 kilowatts
1 horsepower = 1.014 metric horsepower
1 horsepower = .1781 kilocalories per second
1 horsepower = .7068 Btu per second
1 metric horsepower = .9863 horsepower
1 metric horsepower = .7355 kilowatts
1 metric horsepower = .1757 kilocalories per second
1 metric horsepower = .6971 Btu per second

Biomass Energy Data Book
Power Conversion – Unit Converter
Online Power Conversion
Energy and Work Conversion – Unit Converter

References

Energy Kids Page, Energy Information Administration
Energy Information Administration
Wikipedia
Measurement Converter
Biomass Energy Datebook, U.S. Department of Energy
BP Conversion Factors

 

Don Hofstrand, retired extension value added agriculture specialist, agdm@iastate.edu

Author

Don Hofstrand

retired extension value added agriculture specialist
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