I cannot believe how much it costs to heat your house. Last month, our bill almost doubled. I suppose that comes with the unseasonably cold temperatures.

Jessica and I were talking about the price difference between propane (like we had at our old house) and natural gas (like we have at our new house.

Our initial thought was that it should be about the same. But after doing some research, we found that there is a pretty big difference between propane and natural gas.

In order to figure out the cost of propane verses natural gas, I did the following:

  1. I first needed to determine an appropriate conversion between gallons of propane and therms of natural gas. I found a website that listed a rough approximation between therms and gallons of propane:
    100 cubic feet (1 CCF) of natural gas is very nearly 1 therm (0.95 – 1.05, typically, depending on gas analysis). 1 gallon of LPG is about 0.91 therm. (91000 BTU).”
  2. After determining that 1 gallon of Propane = 0.91 therms, I calculated how much one therm equals by doing the by dividing 1 gallon of propane by 0.91 therms. This gives me the solution that 1 Therm = 1.1 Gallons of propane.
  3. Then I looked at our propane and natural gas bills to determine the unit prices for each. For propane, this is $1.49 per gallon. For natural gas, it is $0.80 a therm.
  4. Next I determined a standard measurement to base our calculations on. I chose therms. Since 1 therm = 1.1 Gallons of Propane, we will take 1.1 gallons of propane times $1.49. This will give us an equivalent to the price per therm.
    1.1 * $1.49 = $1.63
  5. We can conclude that, at current market prices (January 1, 2009), natural gas is much cheaper. Currently, $0.80 of natural gas would cost you $1.63 if it was bought in propane.