Prices have come down, thanks to growing demand and cheaper technology. But the idea of buying and installing one can still be daunting, mainly because there are so many variables to consider. Much depends on how much you want the generator to do.
A look at some generator basics:
BUILT-IN OR PORTABLE
The biggest question is whether to buy a built-in generator, which has to be professionally installed and runs on natural gas, or a portable unit, which is cheaper and runs on gasoline. The built-in kicks in automatically in a power outage; the portable has to be started manually.
Built-in generators look similar to air conditioners, usually sitting on the side of a house. They are more expensive than portables; installation could run $1,500-plus.
But they have one big advantage, says Ken Collier, editor-in-chief at The Family Handyman: Once a built-in generator is put in place, you don't have to touch it again.
"They are a great choice for people for whom spending a few thousand bucks for the security of having power is worth it," Collier says.
Portable generators, on the other hand, can be powerful enough to do the trick. But they have to be started manually, and you must have gasoline on hand before any storm. You can't have the gasoline so long that it becomes unusable: Collier says gasoline goes stale after about a month.
In addition, turning on a portable generator often requires several steps, which isn't necessarily easy in stormy, dark conditions.
There are safety concerns, too. Because they are powered by gasoline, portable generators emit carbon monoxide, so they must be set up away from the home and windows.
HOW MUCH POWER
Once you've decided what kind of generator to get, you need to determine how powerful it should be. Do you want to just keep the fridge and a few lights running, for instance, or do you want to light up the whole house?
Russ Minick, vice-president of the country's largest home-generator manufacturer, Generac, recommends buying a generator with at least 5,000 watts, which he says is the minimum needed to power just a refrigerator and lights. Running air conditioning or heat requires more powerful units, he says.
Generac has a sizing calculator on its website, generac.com, to help people decide how powerful a unit they want. The bigger the generator, the more it costs.
Generac recently debuted a baseline built-in generator for less than $2,000 — a far cry from the $8,000 a lesser powered machine cost 20 years ago, Minick says. A portable generator, which runs on gasoline, costs about half that.
THE BIGGER PICTURE
Of course, buying a generator is just one piece of being ready for a power outage, Collier notes. Gassing up your car is crucial in storm preparedness, since it can provide everything from heat and a radio to a place to charge your phone when power goes out.
Having "modern" flashlights — ones with LED lights and lithium batteries — is another priority, Collier says. They use little energy and are powered by batteries that last for years.
"Preparedness is very much a personal philosophy, and spending hundreds or even thousands of dollars being ready is very much a personal decision," Collier says.
Even people who own generators can't let their guard down, he says.
"Generators are not just something that allows you to push a button and be back in business," Collier says. "You have to take care of them. You have to understand what you have to do with the power and what not to do."
"They are not necessarily a simple answer," he says. "But they are very effective."