Dry Your Clothes With Half the Energy

Hydromatic Technologies Corp. says its DryerMiser can cut in half the energy used by clothes dryers. With an Underwriters Laboratories approval under its belt, Hydromatic says it's ready to mass-produce its technology for retrofits and inclusion in mass-produced dryers.

Hydromatic Technologies Corp. is tackling one of the big energy hogs in the home – clothes dryers.

The Orlando, Fla.-based company announced Wednesday that its DryerMiser technology, which it says can cut the energy consumption of dryers by 50 percent, has gotten approval from Underwriters Laboratories, clearing the way for mass production.

The key to DryerMiser's energy efficiency is its use of a heat transfer fluid, said Neal Severn, vice president of new business development at Hydromatic. Traditional electric-powered dryers heat up heating elements to as hot as 1,000 degrees Fahrenheit, then blow air over those elements to bring the temperature within the dryer drum to 150 to 200 degrees.

In other words, "They're using a blast furnace to cook the clothes," Severn said – a technology that hasn't changed much since electric dryers were introduced more than a half-century ago.

By using a heat transfer fluid, which retains heat much longer than does air, to heat the air instead, DryerMiser can cut the typical 5.4 kilowatts that a dryer uses to 3.5 kilowatts or less, Severn said.

The U.S. Department of Energy does not apply the Energy Star rating system from dryers now on the market, "since there is little difference in the energy use between models," according to the Energy Star Website.

Dryer makers, though, disagree with the characterization. Executives at Whirlpool and other companies say they've cranked down energy consumption on dryers over the last several decades in the same way that energy consumption has been turned down on refrigerators and other appliances. Remember how the top of the dryer was always warm when you were a kid? Now they are fairly tepid, thanks to insulation that keeps heat in the drying chamber. Gas-powered dryers, which are more energy efficient, have also increased in popularity, although gas isn't available in all homes.

The problem with electric dryers, however, is the fact that you have to heat a mass of air to a high temperature. Thus, a conventional, contemporary dryer might consume 4,000 watts. (Gas-powered ones require around 400 watts). The hair dryer in your bathroom might consume 1,000 watts or more. The power consumption and efficiency may not be great with electric dryers, they claim, but it's the nature of the beast.

Either way, a new type of dryer will likely introduce greater competition into the market. The DOE is also seeking to institute new standards for energy-efficient clothes dryers by 2011, Severn said.

Hydromatic plans to bring its DryerMiser technology to market through retrofit kits expected to cost about $300 apiece, and projects that customers will be able to be able to pay back that up-front cost through energy savings within three to four years, he said.

The company is also talking to large appliance manufacturers about including the technology in new dryers, though Severn wouldn't identify those companies.