Energy Equivalency Calculation
Using fuel energy equivalents provides the user with a comparison tool for gauging various fuels against a known constant that has relative meaning. A common method of measurement is the Gasoline Gallon Equivalent. The chart at the bottom of this page arrives at the equivalent measurement by comparing the BTU content per unit of each fuel type and then calculating the ratio.
What’s a BTU?
As a basis for determining energy content of a fuel, it is helpful to understand exactly what a BTU (British Thermal Unit) is. Its scientific definition goes something like this: British Thermal Unit - The amount of heat (energy) required to raise the temperature of 1 pound of water by 1 degree Fahrenheit.
Think of it this way: it's basically a standard. Just as PSI (pounds per square inch) is a standard for measuring pressure, so too is a BTU a standard for measuring energy content.
See GGE conversion chart below
| Gasoline Gallon Equivalents | |||
| Fuel Type | Unit of Measure | BTUs/Unit | Gallon Equivalent |
| Gasoline (regular) | gallon | 114,100 | 1.00 gallon |
| Diesel #2 | gallon | 129,500 | 0.88 gallons |
| Biodiesel (B100) | gallon | 118,300 | 0.96 gallons |
| Biodiesel (B20) | gallon | 127,250 | 0.90 gallons |
| Compressed Natural Gas (CNG) | cubic foot | 900 | 126.67 cu. ft. |
| Liquid Natural Gas (LNG) | gallon | 75,000 | 1.52 gallons |
| Propane (LPG) | gallon | 84,300 | 1.35 gallons |
| Ethanol (E100) | gallon | 76,100 | 1.50 gallons |
| Ethanol (E85) | gallon | 81,800 | 1.39 gallons |
| Methanol (M100) | gallon | 56,800 | 2.01 gallons |
| Methanol (M85) | gallon | 65,400 | 1.74 gallons |
| Electricity | kilowatt hour (Kwh) | 3,400 | 33.56 Kwhs |
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