Propane Tank vs. Natural Gas

Propane Tank vs. Natural Gas

A reader is considering buying a home in an area where some homes have piped natural gas, and some have liquified propane. He asked me about the downside of propane, and its expense. My response (which I suspect that others might find useful) is below.

I'm not persuaded that propane is that much different in price than natural gas. You can't really compare the price very usefully; one is sold in cubic feet at a particular pressure; the other is sold by the gallon. Even more complex is that LP gas has more energy than natural gas. Our backup generation produces six kilowatts on natural gas, and seven kilowatts on LP gas.

In Boise, we had a 2755 square foot house, two story (which is very wasteful, because the heat goes upstairs, even when no one is there) and we had only two appliances that used natural gas: the furnace and the water heater. The house was also not as well insulated (R-38 in ceilings and walls). We typically spent about $150-$200 a month in winter, and about $40 a month in summer. I would guess that our annual natural gas bill was about $1200-$1400 a year.

Our new house is in a far colder environment. It is also smaller (2304 sq. ft.), and better insulated (R-50 in the ceiling, R-38 in the walls, and insulation under the floor). We also have, in addition to a furnace and water heater, a propane cooktop, dryer, backup generator and barbecue powered by the propane--and the backup generator and barbecue run a lot. (We have unreliable electric power here, and the generator runs for fifteen minutes every week to keep the battery charged and everything lubricated and in working order.) We fill the tank about twice a year, typically spending about $1000 to $1200 to do so each time, so not quite twice what we were spending in Boise--and operating a lot more appliances.

On the plus side: if all heck broke loose, we could go a couple of months in winter and four or five months in summer without outside utilities. (We would be running the backup generator to keep the furnace fan, well pump, and kitchen electrical systems operating.)

If you own the tank, you can normally get it filled by any available propane vendor, which gives you some flexibility. If you rent the tank (as we do), you normally can only get it filled by the tank's owner.