Is it time to finally buy a generator?

Mary Farrell

Y ou’re settled in safe at home when suddenly the lights go out and the comforting hums of the refrigerator and furnace fade out. As you rummage around in a drawer for the flashlights and batteries, you’re probably kicking yourself for not investing in a generator after the last storm. Don’t let that happen during the next one. The best of the 45 generators in Consumer Reports' tests supply power for everything from the bare necessities to your whole house. Some generators deliver more juice than others. Some, including pricey inverter models, provide power that’s cleaner and won’t make appliances run hotter and sensitive electronics run less reliably. Others include smart features, such as automatic shutdown if engine oil gets low. Here’s how to choose one wisely, install it properly, use it safely, and keep it running as long as possible.

Choose stationary or portable

Stationary models are significantly more expensive, but they start automatically when the power goes out and often supply more power than portables. They also periodically run a self-diagnosis routine that can alert you, via the display panel or sometimes text or e-mail. Running on natural gas or propane, they save you the hassle and safety risks of storing gallons of gasoline.

In addition to costing less, portables can be transported easily to another location. If you go for a portable, one handy new feature to look for is a removable console, connected via cable to the generator. You can plug directly into the console without running extension cords to the generator, which we don’t recommend.

Know your power needs

Unless you want the generator to keep the whole house running, compile a list of priorities for what you want your portable model to power. At the very least you’ll probably want to make sure essentials such as the refrigerator, sump pump, and heating system stay on. Additionally, you can map every outlet and switch in the house so that you’ll know which circuit on your service panel powers what. Two people on cell phones can do that easily. Leave one person manning the panel while the other goes from room to room, checking what works as circuits are switched on and off. A circuit finder, $25 to $30, can help identify which circuit on your service panel powers a given receptacle.

Of course, for a fee a pro can also perform that diagnosis for you. The list of circuits will help you determine just what you want your generator to target.

Consult a pro

Whichever type of generator you choose, consult an electrician to ensure proper selection and installation. If you already know which items in your home you’ll want to power, you could save hundreds by not paying for the labor required to map the circuits. If you’re going for a stationary model, a pro should be able to help with your town or municipal requirements for proper location on your property, noise restrictions, and obtaining permits.

Consider a transfer switch

Extension cords are a hassle, and they can be hazardous. A transfer switch, about $500 to $900 with labor to install, links the generator to your circuit panel. That lets you power circuits, including those for hardwired appliances, directly. You’ll need at least a 5,000-rated-watt generator to use one.

Keep up with maintenance

For a stationary generator, make a habit of checking its display to see whether maintenance is required. For a portable, your owner’s manual will tell you how often to change the oil and which type to use. If your generator uses gasoline, add stabilizer to all of your stored fuel.

Always operate safely

Never run a generator indoors; it creates deadly levels of carbon monoxide. It should be run at least 15 feet from the house, away from doors and windows, and never in the basement, the garage, or any other enclosed space. Don’t run a portable in the rain; model-specific tents are available online.

How much generator do you need?

Here’s what different-sized generators can power. Pick a model that generates wattage at least equal to the total for what you’re powering. Manufacturers also suggest totaling the higher surge watts that some appliances—such as fridges and pumps—draw when they cycle on. One caveat: Small portables require you to connect appliances using extension cords, which is inconvenient and can even be potentially dangerous.

Small portable: 3,000 to 4,000 watts

What it powers: The basics, including:

  • Refrigerator (600 watts)

  • Sump pump (600 watts)

  • Several lights (400 watts)

  • TV (200 watts)

Price range: $400 to $800 for most; more for inverter models that use an alternative technology that makes wattage output smoother so that there are no power surges.

Midsized portable and small stationary: 5,000 to 8,500 watts

What it powers: Same as small models, plus:

  • Portable heater (1,300 watts)

  • Computer (250 watts)

  • Heating system (500 watts)

  • Well pump (1,500 watts)

  • More lights (400 watts)

Price range: $500 to $1,000 for portable; $1,800 to $3,200 for stationary.

Large portable: 10,000 watts

What it powers: Adds one of these:

  • Small electric water heater (3,000 watts)

  • Central air conditioner (5,000 watts)

  • Electric range (5,000 watts)

Price range: $2,000 to $3,000.

Large stationary: 10,000 to 15,000 watts

What it powers: Same as large portable models, plus:

  • Clothes washer (1,200 watts)

  • Electric dryer (5,000 watts)

Price range: $3,500 to $5,000 plus installation.

How much fuel?

A 7,000-watt portable generator will use 12 to 20 gallons of gasoline per day if run continuously for 24 hours. More powerful generators use more fuel. (Store gasoline only in ANSI-approved containers.) A small 8,000-watt stationary model can run for eight to 15 days on a 250-­gallon propane tank or indefinitely on a natural-gas line.

What made Sandy a superstorm?

‘Superstorm’ is now part of our lexicon. But just what made October 2012’s Sandy so super? A hurricane followed by a nor’easter, it packed a potent one-two punch. Winds of 80-plus mph, epic waves, and the storm surge pummeled the East Coast—killing at least 147 and causing about $50 billion in damages. Read our special report, "Lessons Learned From Superstorm Sandy," to help you be prepared when a natural disaster strikes.

This article also appeared in the October 2015 issue of Consumer Reports magazine.



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