YOU ARE HERE: LAT HomeCollections

Motor Controllers for Appliances Save Energy


August 15, 1993|JAMES DULLEY | Dulley is a Cincinnati-based engineering consultant

QUESTION: I can't afford new efficient appliances now, but with higher electric rates, I need to save. Do those inexpensive little "black box" devices I see in hardware stores really improve appliance efficiency?

ANSWER: You are referring to motor controllers for appliances. Plugging your appliances into inexpensive controllers can make them operate more efficiently than when they were new. A controller can reduce electricity usage up to 15%, reduce repair calls, and increase appliance life.

A controller instantaneously monitors the needs of the motor and gives it only enough power to match the load. You can use them on any appliances that have motors--refrigerators, freezers, clothes washers and dryers, dehumidifiers, window air conditioners, sump pumps, tools, etc.

Controllers are particularly effective on old refrigerators because they reduce the heat created by the motor. Excess heat not only wastes electricity, but it also makes the compressor run longer to stay cold.

Older appliances often have motors that are more powerful than needed. These motors run 95% of the time at lower output than they were designed for, so they operate inefficiently and electricity is wasted.

A controller is a small radio-size device that you plug into any wall outlet. You just plug the appliance into the outlet built into the controller. There is an indicator light to show you it is working.

I use a controller on my old refrigerator. Other than a lower pitched and quieter sound of the motor, it operates the same. I move another controller from outlet to outlet when I am vacuuming or running the washer.

Most controllers have built-in high-voltage spike protection. There are many thousand-plus-voltage spikes in your house wiring. One large spike can easily burn out the controls in your appliances. Repeated smaller voltage spikes can slowly degrade the insulation and electronic components.

Soft-start is another built-in feature. This allows the current to ramp up slowly when the motor (refrigerator compressor) starts up. Soft-start reduces energy usage and wear and tear on the motor and components.

Controller brownout sensors can save a motor from destruction. When voltage drops during a brown-out or storm, a motor may stop running and just hum. In this state, it can quickly burn out if power to it is quickly limited.

Proper use habits are also important to keep your old appliance at peak efficiency. Keep them clean, especially refrigerators and clothes dryers.

You can write to me for Utility Bills Update No. 619 listing manufacturers of plug-in motor controllers, specifications, features, prices, and efficiency tips for using your refrigerator, freezer, clothes washer and dryer. Please include $1.50 and a self-addressed business-size envelope. Send your requests to James Dulley, c/o Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, Ohio 45244.

Do Air Conditioners Cause Much Pollution?

Q: Since air conditioners cool the air, do they contribute less than heating systems to the greenhouse effect and air pollution?

A: Running your electric air conditioner is very damaging to the environment. Most electricity generation is from fossil fuels that produce carbon dioxide and contribute to the greenhouse effect. All of the electricity used by air conditioners eventually ends up as heat anyway.

Compressor-type air conditioners contribute to Freon gas in the atmosphere which destroys the ozone layer. Also the air pollution from electricity production is often trapped near the ground by inversions in the summer.

Los Angeles Times Articles