Oct. 5--ORLAND, Maine -- Rufus Wanning led the way to his raspberry garden alongside the Orland River on Saturday, proudly pointing to two large solar panels positioned at a 45-degree angle. Even as the rain poured down, the system was generating electricity.

Wanning was one of thousands of homeowners and companies in 10 Northeastern states that opened their doors Saturday for the annual Green Buildings Open House, the largest sustainable energy event in the Northeast.

Sponsored by the American Solar Energy Society, it coincides with National Energy Awareness Month and was planned to showcase energy efficiency and renewable energy projects and to connect consumers with professionals who can provide services and products to retrofit current buildings.

Wanning and his wife, Margaret De Rivera, have been slowly retrofitting their 1881 farmhouse.

"The average American family puts 50 percent of its energy costs into transportation," Wanning said. "The second-highest expense, 40 percent, is into heating and cooling and heating water."

Along with installing the solar panels, Wanning has put in new energy-efficient windows, removed the dryer (to claim space for the solar battery bank) and purchased energy-efficient appliances.

In a carefully managed booklet, Wanning has detailed just how much he has generated this summer, despite the rain and cloudy conditions.

From June to July, not only did Wanning cover his household usage, but he also banked 7 kilowatt-hours. From July to August, that increased to 67 banked hours.

During the weeks from Aug. 20 to Sept. 18, the solar panels generated 199 kilowatt-hours while the family used only 110.

"We always lose out in November, December and January," Wanning said. "The days are shorter, the sun is lower, and there is more shadow.

"I have never regretted making the switch," he said.

One Maine company that believes it is well-positioned to capitalize on the growing interest in solar technology is EOS Solar. Based in Rockland, the small company focuses on capturing the sun's rays to heat water for use in plumbing and radiant floor heating systems, as well as heated pools and spas in commercial settings.

Rather than the flat, black panels that many people associate with solar technology, EOS Solar uses "solar collectors" that feature long, skinny glass tubes with a copper core.

The glass tubes are double-vacuum-sealed, which the system's designers claim allows the tubes to retain 96 percent of the solar energy that enters them.