Professor David Vogan of mathematics says that one of the most exciting things about having solar panels on his Arlington roof is seeing his electricity meter run backward.
"I am the family member who appreciates that part the most," Vogan said with a laugh.
Vogan has had electricity-generating solar panels on his roof for three years. They were installed as part of MIT's Community Solar Power Initiative, which started in 2002 after the Massachusetts Technology Collaborative, which administers the Renewable Energy Trust Fund, awarded MIT a $455,700 grant.
The MIT Department of Facilities and the Laboratory for Energy and the Environment received the initial grants to launch 40 solar installations on campus as well as at schools, homes and businesses in Cambridge, Watertown, Arlington, Lexington and Waltham. One of those homes was Vogan's.
The grant paid for half the installation, a total of $9,000. Vogan paid $8,000 out of pocket, and he got a $1,000 state tax credit for the rest.
Vogan said he'd thought about putting in solar panels before, but was put off by the cost. When he saw that MIT was offering to help financially, he jumped at the opportunity. "Basically it became an economically feasible thing to do," he said.
"It is fun to be involved with the process of getting these things sorted out," said Vogan, who is no stranger to the green life. He drives a hybrid vehicle and looks for ways to conserve energy in his daily life. "It's been great, basically hassle-free," he said of the system.
There are 24 panels on Vogan's roof. "They provide about one-third (about 2,700 kilowatt hours) of the electricity we use," Vogan said.
Not every house can utilize solar power. The ideal house for such an installation is shade free and faces south, like Vogan's. There are about 22 other installations around the Boston area that are part of the MIT initiative.
Campus installations
On campus, there are three more. "The idea was to use the campus as a learning laboratory for students," said Steven Lanou, the deputy director of the sustainability program run out of the Environmental Programs Office.
The largest campus solar panel installation is on the roof of the Hayden Memorial Library, primarily because of its southern exposure. The 12,000-watt system on the library's roof is comprised of 42 panels, each measuring 2 feet by 5 feet and containing 72 photovoltaic cells. The system generates around 15,000 kilowatt-hours a year--roughly equivalent to the energy needed to power two homes for a year. The production of the electricity results in zero greenhouse gas emissions and supplements power provided by MIT's co-generation plant on Vassar Street.
Solar panels are also installed at the MIT Museum (N52) and at the Student Center; those panels generate a combined total of 11,500 kilowatt-hours.
Although the panels are not providing MIT with a substantial savings, they are raising awareness and visibility, Lanou said. "It has promoted the feasibility of the project," he said. "I think it has been hugely successful."
As for Vogan, he's certainly enjoying "net metering," the process that makes his meter run backward.
When the sun is shining but electricity is not being used, his panels are still producing. That power is then pumped back into the main grid so others can use it. Basically Vogan and his family are selling electricity back to the utility company and the meter runs backward.
In addition, Vogan receives quarterly checks from a government fund that total roughly $1,000 a year. Combining that with the energy savings, Vogan estimates the system will likely pay for itself in 10 years--"a winning proposition."
To learn more about the MIT Community Solar Power Initiative and view photos of solar power panel installations, visit solarpower.mit.edu.
A version of this article appeared in MIT Tech Talk on September 27, 2006 (download PDF).