This is an excerpt from EERE Network News, a weekly electronic newsletter.

February 25, 2004

Energy Star Program Aims to Cut Energy Use in Power Supplies

Here's an energy fact that's sure to appeal to the paranoid: little boxes plugged into outlets around your home and hidden in your electronic equipment are sapping about six percent of the nation's electricity. No, this is not a result of some conspiracy, but rather a consequence of the many electronic devices that run on direct current (DC), the same kind of power produced by batteries. Since our power lines supply alternating current (AC), these devices—our cell phones, telephones, computers, and most other electronic devices—use an AC/DC power supply (generally a transformer) to convert that AC power into the DC power the devices need. Unfortunately, some energy is lost in that power conversion, and for the nation as a whole, that adds up to about 207 billion kilowatt-hours per year.

According to the U.S. Environmental Protection Agency (EPA), more efficient power supplies could reduce that energy use by about 15 to 20 percent. To help achieve that energy savings, on February 23rd the EPA released new proposed energy efficiency specifications and a test procedure for external power supplies, the type you might use to recharge a cell phone. The EPA intends to create strong market incentives for more energy-efficient power supplies through the DOE/EPA Energy Star program, and the new specifications are a first step toward that goal. The EPA and the California Energy Commission also launched a new international design competition for energy-efficient power supplies. The Power Sources Manufacturers Association has endorsed the competition, which will run through 2004. See the EPA press release, and for more information, including the proposed power supply specification, see the Energy Star Power Supplies Web page.