Propane Gallons Vs. Natural Gas Units

Propane Gallons

• The gallon is the standard measurement used in selling propane. The gas is stored in gallon-size cylinders and in large cylindrical tanks located above- or under-ground. Small, gallon sized tanks contain propane that has been converted to liquid propane, or LP, gas. These tanks are commonly available for rental or purchase for use to fuel outdoor appliances such as barbecue grills and outdoor and indoor space heaters. Propane gas used for broader purposes, such as heating and whole home propane fuel, is also measured and sold in gallons; however, the tank size is obviously larger. Propane distributors and resellers lease tanks that can hold 250 to 500 gallons of propane.

Natural Gas Units

• Natural gas is measured in two ways, cubic feet and therms. The cubic foot measurement is more often used for commercial and commodity purposes, such as measuring the amount of gas in pipelines and for transporting large quantities of natural gas to other locations. Cubic foot quantities are calculated on a per thousand basic, or Mcf. The therm measurement is used for billing residential and commercial customers for their natural gas usage.

Propane and Natural Gas Btu Equivilants

• Since both propane and natural gas are used to fuel heating, the standard measurements -- gallons, cubic feet and therms -- are converted to Btu. A Btu measures heat production. A single gallon of propane produces 91,547 BTU, while one therm of natural gas produces 100,000 Btu.

BTU Heating Measurements

• To compare the heat productivity and energy effigies of natural gas and propane, look at home heating. It takes one Btu to raise the temperature inside a room by 1 degree Fahrenheit for each cubic foot of space. If a home is 2,000 square feet and has 10-foot-high ceilings, the home has a cubic square foot measurement of 20,000, or 2,000 multiplied by 10. If the temperature outdoors remained constant at 40 degrees Fahrenheit and the thermostat inside the home is set at 68 degrees Fahrenheit, you would need to raise the temperature by 28 degrees. That would require 56,000 Btu of heat, or 20,000 cubic feet multiplied by 28, each hour. It would take .61 gallons of propane to raise the temperature by 28 degrees for one hour, and .56 therms of natural gas.

Using Measurements for Cost Comparisons

• Compare costs, based on the cost per gallon of propane and the cost per therm for natural gas, to heat the home as described. For example, if propane cost $2.75 per gallon it would cost $1.68 to heat the home per hour -- $2.75 multiplied by .61. If natural gas cost $2.00 per therm, it would cost $1.12 cents to heat the home with natural gas. Using the standard measurements and Btu conversions, find out the current rates for propane and natural gas in your area to compare the differences in heating costs that you might experience.