Denice Walker's friends don't understand why she wanted solar panels on her house in Penn Hills.

"They say 'Denice, that's weird. We're not going to do that,' " said Mrs. Walker, 44.

But her husband, Aaron, 47, and seven children understand. They're used to her energy-saving rules:

• Wash only twice a week with an Energy Star washer and dryer.

• No lights left on and no water running while toothbrushing.

• Thermostat set at 65 degrees in winter (with a lock to make sure).

• 2-minute showers (she keeps a timer in her room).

"That's enough time to lather up and rinse off," she says.

No surprise then that her house on Pearl Road is among 10 buildings featured on the Pittsburgh Solar Tour today and tomorrow. Other stops on the free tour include a house with solar panels on Willard Street in Point Breeze; workshop houses on Sedgwick Street and the Children's Museum in the North Side; a passive solar house in Plain Grove, Lawrence County; Felician Sisters Convent and High School in Moon; Conservation Consultants Inc. on the South Side; and Vox Energy Solutions in McCandless.

The Sedgwick houses belong to local tour organizer L.A. Davis, 51, a landlord and real estate investor from Washington D.C. who saw the light on green living three years ago.

"I came at it as a landlord. I know tenants who have heating bills of $500 or more. That's like a mortgage. I try to explain that by going green you can dramatically reduce your utility bills," he said.

Mr. Davis, who linked the Walkers with electrician Chris Loffert to install their panels, is also a proponent of biomass furnaces, graywater systems and other high-tech energy-savers. He talks about all of them on his radio program My Green Neighborhood, which airs from 3 to 3:30 p.m. weekdays on WPGR-AM (1510).

Solar has a lot more sex appeal than turning down the thermostat and putting in more insulation, he admits. But those steps have a much bigger, faster payoff than any sexy gadget.

"Solar is the last thing you do. If you're thinking about buying solar panels, you should think first about insulation and how many and what kind of appliances you have," Mr. Davis said. "My mother in Florida had four refrigerators and freezers. I told her to get rid of all of them and get one Energy Star fridge and freezer."

The six solar panels installed last week on the Walkers' roof are a logical next step for a family that is already doing more than most to conserve energy and combat global warming. Mrs. Walker said she's always been fascinated by green technology and renewable energy. But growing up in Broadhead Manor, a public housing project, she and her family never worried much about conserving natural resources. Their apartment was always a toasty 80 degrees in winter. Then she met Mr. Walker, whose mother kept the thermostat at 69 degrees in their big house in Wilkinsburg.

"I was freezing when I went over there, but he was used to it," she said.

When they got their first house together and she started paying the bills, she quickly realized that 69 -- or even 65 degrees -- isn't that cold. Her children, who range in age from 9 to 19, didn't agree.

"My 17-year-old said, 'I don't believe this. Mom, you're getting carried away.' You gotta wear more sweaters."

Washing clothes only twice a week was not popular either.

"No way you need to wash more. I said, 'You got 50 outfits anyway.' "

Mrs. Walker is always looking for ways to reduce her energy costs even more. She has started using compact fluorescent bulbs and bought an Englander wood pellet stove at Home Depot. The stove, which is supposed to heat up to 1,500 square feet, is not yet installed in the basement. She wants to use it to supplement their high-efficiency boiler.

Her new solar panels will charge a battery that the family will then draw on to reduce the electric bill. If all goes well, she hopes to add more. She'd love to do net metering, in which solar collectors feed excess electricity back into the grid. As your meter runs backward, you're essentially selling energy back to the power company.

"Imagine a $10 electric bill," Mr. Davis said. "People are doing it."