Energy/units
< Energy
Physicists measure energy in joules, because a joule is based entirely on metric units kg * m^{2} / s^{2}. But a joule is a bit too small for the kinds of calculations we do on this wiki.
Here are some other energy units for comparison:
Unit | Joules | Note |
---|---|---|
watt second | 1 | Electrical power is often measured in watts. A watt is the same as 1 joule per second. |
calorie (lowercase) | 4 | This is not the unit for measuring food. This is an old outdated unit. (show formal definition)|The amount of energy needed to heat 1 gram of water up by 1 degree Celsius. |
kilojoule | 1,000 | |
BTU | 1,055 | British Thermal Unit (used for heating, typically). |
watt hour | 3,600 | Used in battery specs. |
kalorie kcal kilocalorie Calorie (uppercase) |
4,184 | This is the unit used for measuring food energy. For example, "A diet of 2000 Calories" (which would be 8,368,000 joules). (show formal definition of unit)|The amount of energy needed to heat 1 kilogram of water up by 1 degree Celsius. |
megajoule | 1,000,000 | |
kilowatt hour | 3,600,000 | Used on electricity bills. |
gallon gasoline | 131,881,980 | The amount of energy you'd get from burning 1 gallon of gasoline. |
gigajoule | 1,000,000,000 | Enough energy to power a house for a week or two. |
terajoule | 1,000,000,000,000 | |
petajoule | 1,000,000,000,000,000 | Enough energy to power 32,000 homes for a year. |
Mtoe | 41,868,000,000,000,000 | The energy in 1 million tons of crude oil. |
exajoule | 1,000,000,000,000,000,000 | |
quad | 1,055,055,900,000,000,000 | A quadrillion BTU (see unit defined above) |
CMO | 160,000,000,000,000,000,000 | Cubic mile of oil. This is approximately how much energy the world uses in every 3 to 4 months. |
If you want to do more conversions or calculations, you can use the calculator.