A standby generator is a backup electrical system that operates automatically, powering up in case of an electrical outage to supply power temporarily to some or all of a building’s electrical circuits until the power comes back on. When power is restored, a switch automatically transfers the electrical load back to the utility and signals the standby generator to shut off. In areas where severe weather tends to knock out electricity service, or if utility power is unreliable for other reasons, having a standby generator may be a huge advantage—especially if systems like heating and cooling rely on electrical power to keep you warm in the winter and cool in the summer, and keep stored food cold (or frozen) in case of a widespread power outage. In other cases, power may be a matter of life or death—as in situations where a family member relies on medical equipment or even a life-support system powered by electricity.
As home restoration expert Bob Vila notes on his website, if you live in a region that is subject to fairly frequent power outages, it’s wise to consider investing in either a portable or standby generator. Portable generators, powered by gasoline, are more affordable, but they require manual effort to use in a power outage, whereas standby generators automatically provide power during the outage without your intervention.
A good-quality essential-circuit system starts at about $3,000, not including installation. Norh Robinson, owner of Smalltyme Electric in Worth, Illinois, outside Chicago, has installed a number of standby generators in the past decade and estimates they cost anywhere from $1,800 to $10,000, depending on the make, model and capacity. Generally, the higher the capacity, the higher the cost. There are other considerations to be aware of when selecting a generator, including how it’s powered—natural gas, liquid propane or diesel fuel—and how it’s cooled—via liquid or air.
Generators are sized in kilowatts (kW). A 10 kW generator will produce 10 kilowatts, or 10,000 watts of power. You can determine what capacity generator you’ll need by making a list of all the appliances you want to have power during an outage, then adding up the amount of electricity required to start their motors. (Keep in mind that a typical refrigerator uses 700 watts to run, but needs 2,800 watts to start up.) Many generator manufacturers’ websites provide an online calculator to estimate the wattage needed. Robinson says he is happy to advise his customers about what size generator they need to power the required circuits and devices. If you want the generator to power your entire home during an outage, the unit itself and installation will cost more.
Installation costs will vary based on where you live, what your electrician charge per hour, and whether electrical upgrades are required before the electrician can install the generator. Robinson says that 75 percent of the generator’s purchase price is a good estimate of installation costs.
Sometimes electrical upgrades are required to accommodate installing a backup generator. Recently Robinson installed a small standby generator for a customer whose older home had a fuse box rather than a circuit breaker. Before he could install the generator, he had to upgrade the fuses, which cost about $900. Installing the generator cost $1,500, and the generator itself cost about $2,000, for a grand total of $4,400.
If you choose a generator powered by natural gas but do not have a gas line near where the generator is to be installed, you may need to have a plumber install a gas line before the electrician can install the generator. Robinson estimates that in his area this may cost $750 if no digging is required, up to $1,500 if the plumber has to dig a trench to put in a gas line.