SHIRLEY — Last week, Shirley Energy Committee Chair Bryan Dumont reminded Shirley residents that they have until Sept. 30 to sign a contract that will reduce the cost of a solar PV installation on their property by about 40 percent.

At the public information session, billed Solar 201, Dumont introduced the installer selected for the Solarize Shirley program, New England Clean Energy (NECE), formerly New England Breeze, of Hudson, Mass.

NECE president Mark Durrenberger told the audience of about 80 people that he is “a recovering engineer” who started his solar installation company in 2006. Since then, he said, the company has done more solar installations on Massachusetts homes than any other local company.

How to get started

Anyone wishing to get involved in Solarize Shirley should call Dumont (978-425-2726) or visit or

Once NECE has your information, said Durrenberger, a member of his staff will go to Google Earth or Bing to take a look at your home’s orientation and shade to see if it looks like a feasible site for solar. Someone from the technical sales department will then contact you to set up a time to speak with you and/or schedule a site assessment.

Durrenberger recommended that anyone interested in participating, or simply in saving energy, call Mass Save for a free energy audit: 866-527-7283. The National Grid program includes no-cost compact fluorescent lights, a no-cost targeted air sealing, 75 percent off up to $2,000 toward the installation of approved energy-saving improvements such as insulation, and rebates for high efficiency heating and hot water equipment.

National Grid customers can also apply for a 0 percent loan from participating lenders to assist with the installation of qualified energy efficient improvements in their homes. The loans may be available for up to $25,000, with terms of up to seven years.

Evaluating a solar site

Many Solarize Shirley participants have already been contacted by NECE. “When we were looking at the satellite images we were looking to see that there are no trees shading the south side of the roof or part of the ground for a ground mount,” Durrenberger explained. “The area needs sunlight from 9 a.m. to 3 p.m.”

If a tree blocks part of the morning sun, some trees may need to be taken down to make it work. If the site is not a candidate for solar, “you have the option to do a solar hot water system. It doesn’t require as much sun, and a solar hot water system will count toward the tiered (pricing) system,” he said.

Another energy-saving alternative is a solar attic fan, which keeps the hot air moving out of the attic when the sun is shining, so not as much heat radiates down in the house.

Or, said Durrenberger, one might consider an Energy Detective, an in-home electricity monitor that provides real-time data to give you instant feedback on your electricity usage.

“We also offer a home energy diagnostic test,” he said. “We use a fan in the door of the house, close all the windows, and use an infrared camera to see the hot air or cold air leaking in. That is the biggest energy drain on a home, more than bad insulation.”

Solar array and inverter installation

Durrenberger showed photos of a UNIRAC mounting system, Siliken panels, and Solectria Renewables inverters, the latter of which convert DC power from the sun into the AC power used by household appliances. Enphase Energy micro-inverters that connect to individual solar panels and allow each to operate independently can also be used.

Durrenberger described the installation process as finding the rafters and bolting a pedestal to them. He said that a cut is first made around the shingles and flashing attached, “the same as around vent stacks around your roof today. Then we put rails on a roof-mounted system. If it is a ground mount, we use a pole.” Some wiring is done before and after the panels are installed.

NECE will place an inverter in the home near the main electrical service entrance and breaker panel, or place micro-inverters under the panels.

“When the sun shines, you produce clean electricity. Anytime you produce more electricity than you use, the extra goes directly back to the utility grid and your meter spins backwards. How great is that?!” Durrenberger exclaimed. “At night, or when it is not sunny, your electricity comes right from the grid as usual.”

Net metering

What Durrenberger was referring to is known as “net metering.” When you go solar, your electric bill reflects the difference between the electricity you use and the electricity you produce. If you generate more electricity than you need, then the distribution company will credit your account for the value of excess electricity sent to the electric grid.

Net metering credits show up as a dollar amount on your electricity bill. These credits never expire and will continue to appear on your bill until you use them up. Alternatively, you may transfer net metering credits to other customer accounts, so long as the accounts are served by the same distribution company and located in the same load zone.


Durrenberger said that there is a 25-year power warranty on the solar panels, 10-year warranty on the Solectria inverters, 10-year warranty on the racking, 10-year warranty on roof leaks, and 5-year warranty on New England Clean Energy’s workmanship.