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. That is particularly important in cold climates such as Maine’s, where conventional flat solar panels lose a significant portion of their heat to the outside environment, Nate Greenleaf, the director of research and development at EOS Solar, told a group visiting the company’s facility on Saturday.
Greenleaf said the panel of tubes also has been designed to prevent snow from blanketing the tubes.
“We are from Maine and we know what the weather does up here,” Greenleaf said. The company has installed its technology on homes and businesses in New England and Canada, including on a Holiday Inn hotel in Truro, Nova Scotia, and an apartment complex in Weymouth, Mass.
Although solar was the showcase of Saturday’s event, many of the participating homes incorporated other renewable energy features such as passive solar, ground-source heat pumps, alternative building techniques and simple conservation.
Another success story is the Weston Farm in Litchfield. According to agronomist Lauchlin Titus, it is a small- to medium-size dairy farm that produces over 75,000 gallons of milk a year with a herd of 91 cows. In a 2007 energy audit the Weston Farm consumed approximately 19,900 kilowatt-hours — valued at $3,185 a year — to generate hot water for their dairy operation by the use of an electric water heater, Titus said. After installation of an on-demand propane water heater and a 90-tube double-evacuated solar thermal system, the Westons have reduced their electricity usage by 10,500 kilowatt-hours, valued at $1,700 a year.
Titus said that in the summer months, the farm’s solar thermal system preheated the water to 135 degrees or more before it entered the on-demand system. That reflects a temperature rise from the well to the propane system of at least 80 degrees, he said. “That’s a lot of clean energy,” he said.
BDN writer Kevin Miller in Rockland contributed to this report.