BRATTLEBORO — There were smiles all around on Oct. 8 as the ribbon was cut on a 2-megawatt solar project near Interstate 91 between Exits 2 and 3.
The largest commercial solar array in southeast Vermont is owned by Winstanley Enterprises. It covers 12 acres and contains more than 8,000 ground-mounted photovoltaic panels that are expected to generate as much as 40 percent of Brattleboro's residential electric needs.
It may soon have company.
The Windham Solid Waste Management District (WSWMD) wants to build a 2- to 3-megawatt solar array on its capped landfill on Old Ferry Road.
And community solar projects around Windham County are drawing considerable interest.
According to Kim Smith, a planner with the Windham Regional Commission, Vermont has seen a rapid expansion of solar in recent years driven by general cost reductions and state and federal incentives.
Solar also supports the state's “aggressive energy goals” of 90 percent of the state's power coming from renewables by 2050, she added.
According to the U.S. Energy Information Administration, solar accounted for 0.2 percent of Vermont's energy use in 2010, said Smith.
The 2013 Vermont Energy Atlas listed 164 solar net metered sites and 1,507 kilowatts of installed capacity of solar in Windham County.
For energy generation in the county, solar is viable but only as part of a diversified energy portfolio, said Smith.
SPEEDing the process
The Sustainability Priced Energy Development (SPEED) program is helping to fuel the solar boom in Vermont. Solar projects, such as the Winstanley array, that are part of SPEED have all of their energy purchased by electric utilities through a feed-in tariff.
The state has set a goal of meeting 20 percent of its energy needs through the SPEED program by 2017, a figure that goes up to 75 percent by 2032.
Renewable energy sources will account for 90 percent of Vermont's energy needs by 2050.
Green Mountain Power said it will buy all the power generated by the Winstanley array.
Adam Winstanley said that his family's development company was “very patient” in finding a use for the parcel off Technology Drive. Various proposals for the site, including building a YMCA, came and went. But the SPEED program made it possible to build a solar array there.
“It's a great site for solar,” he said. “It's flat, it has good exposure, and it has good connections to the grid.”
All of those things can be said about the proposed WSWMD project at the former landfill.
State law allows the district to construct up to a 5 megawatt solar array, said WSWMD Executive Director Robert Spencer. The capped landfill, however, will likely host a 2- to 3-megawatt array.
The array will act as a group net-metering project similar to community solar projects in Putney and Westminster, Spencer said.
Net metering allows people to buy into a solar array at a remote site.
Setting up the district's net metering portion of the project has proved complicated - and one reason it decided to hire Hull & Associates.
“It's a fairly complex contractual thing,” Spencer explained. “We have no expertise in that. “[Hull] has done a really good job, we believe.”
Consultants from the Dublin, Ohio engineering firm are working with the district to prepare a request for proposals (RFP) for the proposed solar array.
The WSWMD Board of Directors approved releasing a RFP during its Oct. 9 meeting.
The hope is that the project, which is estimated to cost between $7 million and $10 million, will help generate a revenue stream for the district and its 19 member towns.
The district aims to have the array constructed within the year.
Unique challenges
Contructing the Winstanley array was fairly straight-forward.
REC Solar, a national solar provider for commercial customers, was the lead contractor. Integrated Solar of Brattleboro installed the system.
Work started on the site on May 15 and was finished in late September. About 75 workers, most of them based locally, put in a combined 18,000 hours on the project.
But building a solar array on a flat parcel is one thing; building a solar array atop a capped landfill is another. Capped landfills are essentially brownfields that can't be used for other activities such as farming, said Spencer. It makes them ideal locations for solar arrays.
Still, the array's construction can't penetrate the landfill's cap, he added. Compromising the cap could wind up contaminating the groundwater.
Brattleboro capped its landfill with a two-foot thick layer of clay some 20 years ago.
“A good cap keeps rainwater and snowmelt from percolating down into the water,” Spencer said.
Spencer added that the number of developers with experience building solar arrays on landfills is increasing.
He said he recalls that when he attended a workshop in Massachusetts two years ago, six landfills in the state had solar arrays. Now there are more than 20 in Massachusetts alone, with Greenfield, Mass., maintaining one of the region's largest.
The district aims to keep the project cost neutral for its member towns, Spencer said.
Whichever developer the district hires to construct the solar array will assume all capital construction costs, Spencer explained. The developer will make money from the solar array by taking advantage of federal tax subsidies and in the power purchase contract it will negotiate with the district.
Once completed, the solar array will become another piece in the district's renewable energy puzzle.
For years, the district has generated a modest amount of electricity from burning landfill methane. The district also hopes to install an anaerobic methane digester that uses organic waste to power generators.
A solar-powered future?
At the Winstanley ribbon-cutting, Lt. Gov. Phil Scott said that Vermont now was the top state in the nation in solar jobs per capita.
“Renewable energy projects like this solar installation are a boon for our environment and our economy,” Scott said. “When we invest in projects that reduce our dependence on foreign oil, we grow opportunities for our skilled local workforce, and plant the seeds for Vermont to sustain itself, independent from outside influences.”
However, solar is considered an intermittent energy source, meaning that the panels do not generate power consistently. The panels generate peak power only when the sun is out, as opposed the nighttime or days with heavy cloud cover.
But Smith said renewable energy fits well into the summer electricity needs of Windham County, when air conditioning puts extra demands on the regional power grid.
ISO New England, the manager of the region's electric grid, still looks for so-called “base-load” power sources to maintain reliable power, said Smith.
Smith said that communities would be wise to take up siting and zoning solar and other energy projects.
Building a solar farm on agricultural land, which Windham County has in relatively short supply, damages fertile land that is at a premium, said Smith. Building in flood plains can also intensify flooding downstream during high-water events, he added.
Solar is a low-impact energy source after installation, Smith said. The concrete footings and base, however, do affect the land and can be difficult to remove.
The WRC addressed solar and other renewables in its regional plan for the first time this year, said Smith.
“This is a conversation we need to be having,” she said about siting solar projects.
With more individuals and companies installing solar projects, renewable energy is still in its wild-west phase in regards to planning and zoning.
In addition to solar, Smith said, there is also increased interest in biomass. Wind also seems to have equal parts supporters and opposition.
Increasing energy efficiency in homes, however, remains important.
“And that's one of our greatest opportunities,” Smith said.