Dan Reicher flips open his briefcase and extracts two cherished bits of paper: A picture of his wife and daughter, and his lastest Pepco bill.

"Thirty-two dollars and seventy two cents," he all but crows. Between May 25 and June 24, that is what it cost to run the central air conditioning, lights, dishwasher, refrigerator, stereo system, television, computer and every other electrical appliance in his three-story home in Chevy Chase. "My sister lives two blocks away and her bill was about $100. It was the same for some of the neighbors," he said.

Reicher, the Department of Energy's assistant secretary for energy efficiency and renewable energy, owed so little because his heavily "green" home produces as well as consumes energy.

There is evidence that the solar energy movement is growing. Last month, the Pentagon installed on its lawn a new generation of solar panels that turn sunlight directly into alternating current without inverters. By summer's end, the panels -- visible from Route 395 -- are expected to produce 30 kilowatts of power, about enough to meet the daily needs of 10 average homes.

And the Smithsonian has mounted an exhibit of solar-driven or light-producing objects ranging from a fountain, lawn mower and chairs to an enormous tent made of thin photovoltaics that illuminate its tall mast.

Organized by the Cooper-Hewitt National Design Museum and displayed in New York last year, "Under the Sun: An Outdoor Exhibition of Light" is at the Enid A. Haupt Garden of the Smithsonian Castle through Sept. 6.

In his Chevy Chase house, Reicher is taking advantage of a law passed in 29 states -- including Maryland and Virginia, but not the District -- allowing consumers to "sell back" to their utility companies whatever surplus power they generate.

Only a handful of customers do this, say Potomac Electric Power Co. and Virginia Power officials. And most of it comes from wind or water, said Jim Norvelle, a Virginia Power spokesman. "There isn't much solar because the East Coast is geographically challenged by a lot of trees and not so much sunlight."

At Reicher's house, 28 photovoltaic panels are mounted on the roof to convert sunlight to electricity. The panels normally sell for $8,000, but Reicher paid only $3,700, and the state of Maryland subsidized the rest from funds collected from oil companies fined for overcharging customers.

The house has two electric meters. A conventional meter outdoors measures consumption. It is wired to a second meter in the basement, which records how much energy the south-facing, solar panels generate. When there is an energy surplus, the outside meter runs backward. Reicher and his wife, environmental consultant Carole Parker, sell the overage to Pepco's areawide grid.

Reicher and Parker were among 10 families who qualified for the first year of a 12-year national program aimed at putting 1 million solar converters on U.S. rooftops by 2010. This year, 20 Maryland households will be chosen.

The panels connect to an inverter in Reicher's basement that turns direct current into alternating current for a seamless connection to the power grid.

If all this sounds enticing, you can do more than pine for a sun-powered grass cutter. On Aug. 18 from 7 to 9 p.m., the Smithsonian will hold a free workshop on photovoltaic systems for the home at the S. Dillon Ripley Center, 1100 Jefferson Dr. SW. Call 202-357-3168 ext. 103.

Who knows? By next summer, you, too, could be bragging about a $30 electric bill.