What is the best back up generator, natural gas or propane?

December 2, 2008

Q: I want to have a generator as a backup in my home for emergency purposes. I am considering a gasoline one, which I would like to have wired to permit switching when needed. Now I see propane portables in some stores. Which type would be best as a back-up emergency system?


A: Backup generators can be useful anywhere there are frequent power outages, but they can also be very dangerous if they are not installed properly. All portable or fixed generators must be connected to the residential grid using a proper CSA-approved transfer switch installed by a registered certified electrician. An electrical permit is required for the installation.

A major decision for homeowners considering a backup generator is choosing between gasoline or propane, as well as one of the more convenient fuels, natural gas.

Each source has its own pros and cons, but the decision will depend on what a home already has installed. If you live in an area where natural gas is available this would be the best for you since it would be the most convenient and requires less maintenance.

For homes without natural gas, propane is a good alternative. Both natural gas and propane tend to last longer and burn cleaner than their gasoline counterparts. Gasoline generators are by far the most common type since gasoline is readily available and still remains a relatively inexpensive fuel in comparison to propane. But a gas generator usually requires frequent maintenance, plus storage of gasoline, which has a relatively short shelf life.

When choosing a backup generator, it is worthwhile to shop around and talk to various distributors and your electrician to determine a unit that will suit your needs. Typically, the lower-power and portable units use gasoline, whereas larger units, especially permanent installations, will likely use propane or natural gas.