Energy adviser: Take care with generators



It’s that stormy time of year when a big wind gust could knock out power.

Even though extended power outages are rare in Clark County, knowing you have backup options may be comforting — especially if you have a freeze.

Generators can provide peace of mind, but they must be used with care.

“Generators are combustion engines, so they produce heat, exhaust and carbon monoxide,” said Michael Getman, Clark Public Utilities safety manager. “Never use it indoors or in an enclosed space such as a garage. Carbon monoxide poisoning can occur silently and quickly.”

For safety, install a carbon monoxide alarm to detect poison in the air. These alarms should be certified to meet the requirements of the latest safety standards.

There are two kinds of residential-type generators — portable and permanent. Both should be operated at least 10 feet from the house, with at least three to four feet of space on all sides for adequate ventilation. Remember to store fuel for the generator outside of your home in clearly marked, non-glass safety containers. Only refuel the generator when it is off and cool as gasoline spilled onto a hot engine could cause a fire.

Permanent generators can provide up to 20,000 watts of electricity. They are wired into the electrical system of your home, and can keep several electrical appliances operating at once, depending on generator size. Permanent generators, which can cost anywhere from a few thousand to $20,000, typically run on propane.

Portable generators are designed to supply temporary electricity to individual electric appliances and they are not designed to power your entire home. If you just want to run your TV, fridge, coffee pot and a DVD player, a generator putting out about 2,000 watts may be enough. If you want something that will power your furnace, a well pump and fridge, then 5,000 watts is probably the minimum. You’ll also want to consider the additional electricity needed when starting up the motor in an appliance such as a refrigerator. Start-up wattages can be as much as three to five times more. Other factors to consider before buying a generator is the noise level, size, portability and starting mechanism.

Consumers can review a generator buying guide from Consumer Reports at: In the article they include a link to a wattage calculator which lists the wattages of most home appliances:

Typically, homeowners will hook up a portable generator to a specific appliance, such as a refrigerator, using an extension cord.

“You want to make sure you are plugging the appliances into the portable generator, not plugging the generator into the household system,” Getman said. Plugging a portable generator into a wall outlet bypasses built-in household circuit protection devices. It can also cause backfeed, which is extremely dangerous and can electrocute utility workers and even neighbors served by the same utility transformer.

If you want to use a portable or a permanent generator to put power into the house circuitry you must install a transfer switch, if your house doesn’t already have one. That switch should be installed by a licensed electrician. The transfer switch will cut your home’s connection to the utility’s electric grid before you start the generator and prevent backfeed. If there’s any doubt that your home is disconnected from the grid, always use an extension cord with a power strip directly from the generator to the appliances you’re powering.Energy adviser is written by Clark Public Utilities. Send questions to or to Energy Adviser, c/o Clark Public Utilities, P.O. Box 8900, Vancouver, WA 98668.