How long will standby generators run during an extended power outage?

In theory, standby generators will run indefinitely or for however long fuel is supplied to the generator.   Most standby generators are fueled by natural gas (NG) and, thus, there is no need for a fuel tank since there is an endless supply of NG from your utility company.  If your standby generator is fueled by liquid propane (LP) or diesel, there will be a fuel tank and generator run time will be limited by the amount of fuel remaining in the tank.

During an extended power outage lasting several days, you will want to conserve generator usage, especially if your generator is fueled by LP or diesel.  Most diesel generators have a 24-hour fuel tank, although 48- and 72-hour fuel tanks are available.  If your generator is diesel or LP, you probably already have a relationship with a refueling service that will stop by your home or business to top off your tank.  During extended outages you will need to stay in touch with your fuel service provider to make sure the tank is topped off periodically.

Regardless of the fuel source used, it might be a good idea to periodically shut the generator down for purposes of engine cooling.  Residential customers might choose to shut the generator down at night while sleeping or during working hours when you’re away from home.  This is especially true if the generator’s engine  runs at 3600 RPM.  These engines run hot and use oil.  Be sure to check the oil level during peiodic shut downs.  Add oil, if necessary, but do be careful and don’t overfill as this  can cause problems.

The best generators have engines operating at 1800 RPM.  These engines use less oil, run cooler, and are perfect for extended power outages.   While more expensive than 3600 RPM generators, these engines are also more reliable and fuel efficient.  If your goal is to have absolute reliability, be sure to choose a generator with an engine running at 1800 RPM.  The 3600 RPM generators work fine, but they are best suited for shorter power outages.  If you happen to go through an extended outage with one of these generators, be sure to shut the unit down periodically for engine cooling purposes, and keep an eye on the oil level.

Diesel generators are generally regarded as being the most reliable.  We’ve all heard the John Deere motto, “Runs like a Deere” and, so, it’s not too surprising to find a John Deere engine inside many diesel generators.  The two downsides to owning a diesel generator is (1) cost … expect to pay upwards of 25% or more for diesel, and (2) the need to keep an eye on the fuel tank.

If you are in the market for a new generator, Buckeye Power Systems has a wide choice of generators that can run off NG, LP, or diesel.