The 20% proposed improvement would save enough energy to light all U.S. homes for two years, equal to the output of 37 400-megawatt power plants, according to The Associated Press. Complying with the Bush standards would add $213 in up-front costs to the average $2,236 price of a home central air-conditioning system, the government estimated. Buyers would recoup the extra cost through lower utility bills over 9.8 years. The added up-front costs for heat pumps would be $144 more than the $3,668 average price.

The Clinton standard would add $335 to the price of air conditioners, $332 to that of heat pumps and extend the payback to 11 years.

"The Department of Energy's decision is an important first step toward establishing a fair and equitable standard that will help our country conserve energy while meeting a vital need," said Clifford H. Rees Jr., president of the Air-Conditioning and Refrigeration Institute. ARI and the National Association of Home Builders had urged the DOE to reconsider its SEER 13 position.

However, opponents to the Bush proposal questioned the legality of the new administration to ease a regulation adopted as final in January. A press release from the Appliance Standards Awareness Project, a coalition of consumer and environmental groups, stated that the action violated the National Appliance Energy Conservation Act signed by President Reagan in 1987, which prohibits rollbacks, and the Administrative Procedures Act, which defines the process for establishing new rules.

The director of the Appliance Standards Awareness Project, Andrew deLaskie, told The Associated Press that the DOE's action will be challenged in court.

"I can't think of a more clear-cut case of where special interests have gotten their way at the expense of the public," deLaskie told AP. "After a month of analysis they're going to turn back what was developed after six years. That's reckless."

He also cited increased power bills for consumers and more air pollution as a result of the DOE proposal.