Q: We sometimes have electric power outages. To keep things running, I plan to buy an emergency generator. What are available and are they efficient?
A: The most effective and convenient types of home emergency standby generators are 8- to 10-kilowatt (KW) output systems. These systems are placed outside your house and look very similar to an outdoor central-air conditioner unit. You can get systems as large as 20 KW output.
Inside your house, near your existing circuit-breaker panel, you put an automatic transfer switch. The electronic circuitry senses when the power goes off or the voltage is too low. Automatically, it starts the generator motor and switches your house power from the utility lines to your own generator.
Within less than a minute, you have electric power again during an outage. It also starts the generator motor once a week for a short period to make sure it is operating properly. Manual transfer switches are available that require you to physically throw the switch.
The 8 KW to 10 KW systems have small air- or water-cooled engines that are designed to operate on natural gas, bottled gas or gasoline.
The home-sized generators are efficient. When powered on natural gas, the fuel cost alone is equivalent to about 12 cents per kilowatt-hour of electricity produced. The only additional operating cost is generally changing the engine oil once a year.
To determine the size of the emergency generator you need, add up the watts used by the appliances and lights you want to keep running. This is usually shown somewhere on the products' nameplates.
For example, a furnace blower uses about 1,000 watts of electricity, color TV 300 watts, gas dryer 400 watts, freezer 500 watts, microwave oven 800 watts.
You can write to me for "Utility Bills Update No. 015," listing names, addresses, and telephone numbers of manufacturers of automatic emergency generators, product information and specifications, and a chart showing the wattage usage of common appliances. Please include $1.00 and a stamped, self-addressed, business-size envelope.
Write to James Dulley, c/o Baltimore Sun, 6906 Royalgreen Drive, Cincinnati, Ohio 45244.