BRATTLEBORO—Pipes protruding through waves of green grass like periscopes are the only sign that a capped landfill sleeps beneath the soil.
Soon, the Windham Solid Waste Management District’s old 25-acre landfill may hold a sea of solar panels.
Inside the WSWMD’s headquarters on Old Ferry Road, machines spin and clank, separating cardboard from paper and plastics from aluminum. The district sells recyclables to keep assessment costs down for its 19 member towns.
In the conference room, part-time Executive Director Robert Spencer spreads on the table four bids from engineering companies in California, New Hampshire, Ohio, and Guilford.
The district seeks an engineering firm to represent it in its goal to build a solar array atop the old landfill. The consultants are to develop construction plans and financing for a solar project and help the district navigate power purchase agreements and state statutes such as Act 248, said Spencer.
Once the plan is ready, the consultants will vet and hire an engineering firm to install the solar project.
The more revenue the WSWMD generates the less it needs to charge its member towns, said Spencer.
Along with selling recyclables to the commodities market, Spencer said the district has started selling soil it has made from organic waste, and is considering installing an anaerobic digester.
It’s possible that, with enough solar, bio-gas, and recyclables, the district could sustain itself, Spencer said.
Lots of interest
Spencer said he received about 30 inquiries to the WSWMD’s request for proposals for the solar project.
The district previously considered constructing a solar array on its old landfill. State net metering laws, however, capped the size of solar projects there at 500 kilowatts. Limited to that size, an installation isn’t feasible for the district, he said.
The outlook changed in March when the Legislature updated net metering laws to allow solar arrays up to 5 megawatts, said Spencer. Increasing the limit spurred the WSWMD to send out requests for proposals.
Spencer credits outgoing Sen. Peter Galbraith, D-Windham, for helping bring the issue of watt caps to the Vermont Legislature.
Now the district anticipates installing a 2-megawatt solar array and is racing the expiration of a federal subsidy in 2016 that would give the project a 30 percent investment tax credit.
“That’s a very large incentive,” he said.
One of the district’s goals for the solar project is for its 19 member towns to have first dibs on any power generated here.
In Spencer’s opinion, old landfills make perfect spots for solar projects. After all, he said, building on landfills means not building on prime agricultural land.
“That should be saved for higher and better uses,” said Spencer.
By law, no habitable structures can be built on landfills, he added.
Closed and capped with a layer of clay and special lining in 1995, the landfill contains hundreds of thousands of tons of trash from more than 30 years of use, said Spencer.
The cap keeps water from filtering through the trash and into the ground water.
“Whatever we do, we don’t want to jeopardize the integrity of the cap,” said Spencer.
Which is another reason for calling in consultants who know how to construct arrays at landfill sites rather than drill posts through the cap as step number one, said Spencer.
He explains the district has harvested methane, a byproduct of organic decomposition, from the landfill for electrical generation but the output has dwindled to less than the equivalent of 100 kilowatt hours of electricity.
The WSWMD’s executive board and planning committee will put together criteria and review the four proposals. Board members will select which consultants it wishes to interview at the board’s July 24 meeting.
The board hopes to hire the consultant quickly so the consultants can have a full RFP ready to send out by October. Construction on the array could start by spring, Spencer said.