Home and the Range

Engineers are experimenting with bold ideas and minor tweaks to squeeze out new efficiency gains in household appliances.

Some improvements may go unnoticed, like new materials and adjustments to motors. But engineers are also rethinking basic ways in which traditional white goods work -- exploring how one appliance can harness heat produced by another, for instance, or using ambient warm air inside a home.

Appliances already have made substantial gains in energy efficiency over the past two decades, driven by government standards. A new refrigerator uses about half as much electricity as one bought in 1990, for instance, while a clothes washer requires nearly 70% less electricity per load, according to the Association of Home Appliance Manufacturers, an industry trade group based in Washington, D.C.

Small efficiency gains spread across millions of homes hold huge promise for energy savings as a nation. The trick is to keep coming up with products that reduce energy needs while still satisfying consumer demands.

Household efficiency is the biggest potential we have to reduce energy use in the U.S., says Jeff Christian, a researcher at Oak Ridge National Laboratory in Oak Ridge, Tenn. But whether that potential is fulfilled, he says, is "in the hands of 120 million individual decision makers."

Here are some of the ideas being discussed, and products being worked on.

Microwave Dryer?

One idea that's been kicked around for years is a microwave dryer. Drying towels with the same technology used to reheat leftovers has its attractions. A microwave dryer would work much faster than a traditional dryer, using less electricity. But serious hurdles exist: Metal buttons and zippers could spark, just like a fork accidentally left in a microwave oven, says Tom Reddoch, director of energy utilization at the Electric Power Research Institute, a nonprofit based in Palo Alto, Calif.

For the near future, consumers are more likely to see tinkering with existing types of appliances than whole new categories. Lighter materials in a washing machine, for example, will reduce the power needs of its electric motor, while improved insulation will cut the power a refrigerator needs to keep food cool, says John Weinstock, vice president of marketing for digital appliances at LG Electronics USA, a unit of LG Electronics Inc. of South Korea.

General Electric Co. plans to introduce a water heater in 2010 that it says will use half as much electricity as a standard electric water heater -- now the second-largest consumer of power in a home, after heating and cooling. The new water heater incorporates heat-pump technology to absorb heat from the air and transfer it to the water, says Kevin Nolan, vice president of technology for GE Consumer & Industrial.

Transferring heat requires a lot less power than generating it, the power research institute's Mr. Reddoch says, so heat pumps are likely to find other uses as well. He imagines one day there will be a "modern clothesline" that would draw on warm air from outdoors to dry clothes in a highly efficient dryer.

Refrigerators have already slimmed down their electricity needs. But further changes are in store, such as having several small doors instead of one big one. Each time a fridge door is opened, a blast of warm air enters, and a lot of electricity is required to bring the temperature back down. Having several smaller doors can provide quicker access to items and allow less cool air to escape. In Japan, such models are already on the market, but industry insiders say U.S. consumers may resist such a big change if it doesn't clearly make their lives easier in some way.

U.S. consumers have been cool to a new kind of energy-saving stove now popular in Europe. Induction stovetops, which feature a smooth, glass cooking surface, are one-third more efficient than either open flames or electric ranges, industry experts say. While range stoves heat coils that in turn heat the food, an induction stovetop creates an electromagnetic field that creates an electric current heating the metal pan or pot on top of it. A cook can change the desired temperature instantly. The food cooks faster and with more precise control. Despite a slow start, Whirlpool Corp. says it is starting to see increases in U.S. sales of induction stoves.

Looking at how appliances can work together may achieve much bigger energy savings than tinkering with individual pieces. For instance, the heat in a clothes dryer is currently wasted when it goes out the exhaust vent. Whirlpool engineers are looking at using that heat to warm water for the washing machine, thus reducing the load on a home's water heater, says Henry Marcy, vice president of global technology for the Benton Harbor, Mich., company.

Whirlpool is also exploring the possibility of a household system that captures and reuses heat that otherwise is wasted. But the company says it isn't ready to commercialize such a system, because for it to work, homes may require significant changes.

Smart Power Strips

Some new products try to help consumers themselves be smarter about their power usage.

While many major appliances use less electricity than they did two decades ago, households are using more, due to the boom in electronic equipment -- especially home-entertainment gear and chargers for personal electronic devices. The costs add up with each charger left plugged in or DVR running 24 hours a day.

Motion-sensitive power strips may help. Watt Stopper Inc., a Santa Clara, Calif., unit of France's Legrand SA, makes a power strip that works in combination with a motion detector to shut off all the electronics plugged into it after determining no one has been in the room for a predetermined length of time.

Another idea is "smart" appliances. Most households now pay a flat rate for electricity. But power prices actually fluctuate throughout the day, depending on usage levels. According to the power research institute's Mr. Reddoch, there are devices that alert customers to price changes in real time, as well as appliances that can be set to respond on their own to price shifts.

Some of these changes are starting to trickle into the market, such as a light that changes colors depending on power prices. Also, GE plans to release appliances next year with displays that indicate real-time power prices. The Fairfield, Conn., company says the appliances will be programmable to run when the rates are least expensive.

This kind of smart technology has huge potential, says Mr. Reddoch, who adds: "We don't convey to our consumers what it really means to use electricity."