Living Lightly on the Grid

Tidwell and his then-wife started with a $7,500 home-equity loan. They replaced incandescent light bulbs with more costly compact fluorescent bulbs, which work in the same fixtures and provide the same light but use a third as much energy. They bought an EPA-designated "Energy Star" refrigerator, which cost $150 more but used less than a third as much power.

For heat, they replaced a natural-gas furnace with a $2,400 stove that burns corn kernels. Because corn consumes carbon dioxide as it grows, burning it doesn't release new greenhouse gases, he said. The corn, of a type used for animal feed, is grown in Mount Airy and brought to Takoma Park in a truck that burns soy-based biodiesel fuel. In town, the corn is stored in a 25-foot-tall silo owned by a community cooperative. In especially cold months, Tidwell has to get a load once a week.

One recent chilly day, there were flames eight inches high in the stove as kernels tumbled slowly down a tube and into the fire. A thermostat in the next room read 70 degrees.

"That is 100 percent corn," Tidwell said.

On his roof, Tidwell put an array of photovoltaic solar panels to produce electricity. He received grants to help pay for the panels and installed them himself, holding the cost to about $3,400. He also got a deal on panels that heat water: $1,000, or about half current prices, for a set pried off the roof of a departing Clinton administration official.

Even with those changes, Tidwell's house doesn't supply all its power. He still gets about half of his electricity from the grid and about 40 percent of his hot water from a backup natural-gas system. He pays about $200 extra a year to buy power generated by windmills -- enough "clean energy," he said, to offset the fossil-fuel energy he uses for his house and car. The money goes to a kind of brokerage, which passes it on to the wind-power producer.

The lights in Tidwell's house, which he shares with his school-age son and a housemate, are kept off in daytime to save energy. All the heat comes from the stove, on the first floor. When the corn runs out, so does the heat. If he doesn't plan ahead, that can mean a late-night run to the silo. But Tidwell said he is proud that the place is so close to normal.

"There are people who say it cannot be done," said Tidwell, who holds open houses every two months to show people what he is doing. "I've done it, and I've done it on a budget, and I have a great life."

Other homeowners across the area have made similar changes. In the Kalorama neighborhood of Northwest Washington, Chris VanArsdale, 39, a real estate developer, added solar panels and wall insulation made from sucrose and soy. The insulation cost at least twice as much as conventional fiberglass, he said, but it does more to keep the house warm or cool, depending on the season. His wintertime gas bills dropped from $700 a month to about $100, he said.

In Arlington County, Scott Sklar uses solar-panel arrays, a small wind turbine and even a small hydrogen fuel cell to power his house and a two-story building out back.

"I don't want to have high utility bills, I don't want to have outages and I don't want to pollute the planet," said Sklar, 55.

He uses the house as a kind of showpiece for his business, which advises business owners on ways to cut back on energy use.

But, for now, low-carbon homes can come with very high price tags. Electricity-generating solar panels can cost as much as $30,000, and water-heating panels can top $9,000. The District and Maryland provide financial help, but reimbursements cover just a fraction of the cost.

The cost and the difficulty of finding contractors have frustrated a group of Mount Pleasant residents who are seeking to put solar panels on their roofs. Anya Schoolman, a member of the Mount Pleasant Solar Cooperative, said the group e-mailed about 50 contractors. Two called back, she said.

"It's both more expensive and harder than I thought," Schoolman said.

And nature isn't tremendously helpful. Sklar said his windmill works, but others in the field say the area generally has too little wind to generate reliable power. The area also lacks the solar-power potential of the Southwest.

"We have a lot of people come to us and say, 'I want to be off the grid.' And that's just not going to happen around here," said Jason Holstine, who runs the Amicus Green Building Center in Kensington. Residents will always need backup power, he said.

But Holstine said that shouldn't discourage area residents from taking intermediate steps, such as installing energy-efficient light bulbs and appliances. He recommends that customers hire an "energy auditor" to inspect their homes and find ways to save energy -- and possibly make some of their own.

"It can cover an awful lot of conscience," he said.