Six years into the Bush presidency, the administration unveiled its first new upgrade to energy-efficiency standards Friday with all the fanfare of a funeral, burying notice of it in The Federal Register.

But the energy savings accrued under the new standard for electrical transformers – those gray trash-can-like metal cylinders that hang on utility poles from Pasadena, Calif., to Poughkeepsie, N.Y. – are not insignificant.

Nearly all the electricity in the US moves through those gray boxes, so even a fraction of a percent efficiency gain will save as much electricity over 29 years as 27 million households use annually, reports the US Department of Energy (DOE). That would eliminate hundreds of millions of tons of carbon-dioxide emissions and the need to build almost five new medium-size coal-fired power plants.

Transformers are just the beginning. Sued by environmental groups for foot-dragging on efficiency standards, the DOE in 2006 agreed to a five-year timetable for developing new standards on everything from pool heaters to light bulbs. (By contrast, the Clinton administration had half a dozen new efficiency standards in place after six years in office.)

But energy-efficiency advocates are claiming only a partial victory because, in the words of Steve Nadel of the American Council for an Energy Efficient Economy, the DOE "left energy gains sitting on the table."

Many worry that the transformer standards are a sign of things to come.

New efficiency standards are usually welcomed when environmental, efficiency, and industry groups reach a "consensus standard." In this case, however, the DOE rejected it and adopted a standard that will yield one-third less energy savings.

"We're required to balance a number of factors, including what is both technologically feasible and economically justified," says DOE spokeswoman Megan Barnett. "We performed substantial analysis and gave extensive attention to comments and proposals. And we raised the required level of efficiency for distribution transformers."

In The Federal Register, the DOE cited concerns that the core of the devices may cost more. But The ABB Group, the biggest transformer manufacturer, endorsed a higher standard, although others did not.

The electric utility industry, too, wanted a tougher standard. One reason is that better transformers can take the heat. In July 2006, nearly 1,400 transformers blew during a heat wave in northern California, leaving more than 1 million people without power, news media reported.

"The new standards aren't as tough as we had hoped," says Ed Legge of Edison Electric Institute, a Washington advocacy group representing investor-owned utilities that supply electricity to 70 percent of the nation. "I wouldn't say it [the new standard] is the highest possible. But it's better than the initial proposal a year ago. We would have liked more, and we'll keep pushing."

Since the 1970s, efficiency-standard upgrades have been a key to reducing the amount of power needed for US economic growth, says David Goldstein, energy program director for the Natural Resources Defense Council. He isn't sure why the DOE opted for lesser standard for new transformers – or what it portends for new appliance standards in the pipeline.

"We thought this was the least this DOE could do," he says of the rejected consensus standard. "It turned out it wasn't."