Selecting A Fuel

One somewhat simple way to evaluate heating options is to compare the cost of the fuel. To do that, you have to know the energy content of the fuel and the efficiency by which it is converted to useful heat. Fuels are measured in physical units, such as gallons of oil or propane, cubic feet of natural gas, or kilowatt hours of electricity (kWh). They are also measured by heat content. In the United States, the most commonly used value for expressing the energy value or heat content of a fuel is the British thermal unit (Btu). One Btu is the amount of energy needed to raise the temperature of one pound of water 1°F when water is at about 39°F. One “therm” is 100,000 Btu.

FUEL COST COMPARISON

Electricity: $ per kwh x 293 kwh/1,000,000 divide by efficiency = cost of 1,000,000 btus
Fuel Oil: $ per gallon x7.21 gal/1,000,000 divide by efficiency = cost of 1,000,000 btus
Natural Gas: $ per therm x 10.0 therm/1,000,000 btu divide by efficiency = cost of 1,000,000 btus
Propane Gas: $per gallon x 11.0 gal/1,000,000 btus divide by efficiency = cost of 1,000,000 btus