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Construction begins on landfill solar array

WSWMD director sees broad benefits in 5-megawatt project

BRATTLEBORO — After nearly four years of planning, work has begun on the 5-megawatt net-metered solar project on the town's former landfill at the Windham Solid Waste Management District's Old Ferry Road facility.

The project is behind schedule. In March, 2017, an official with Sky Solar, the project owner, told the District's Board of Supervisors construction on the photovoltaic solar array would begin in July and the project would go online in November.

Construction on the 17-acre parcel, which Sky Solar is leasing from the District, began in early January.

In the past month, Gransolar Group, a Spanish company hired by Sky Solar to oversee engineering, procurement, and construction of the solar array, has placed two engineers on-site.

Gransolar hired Dummerston-based Evans Construction for site work, and in January, crews began preparing the property for the installation of 16,000 solar panels. They are building temporary and permanent access roads, and storm-water berms and other erosion-control applications.

In early February, Green Mountain Power began sending their trucks, equipped with giant drills, to install new utility poles and a transformer at the northwest corner of the District's 25-acre property.

Next up, crews will build the concrete pads for the transformers, which convert the electricity generated by the solar panels from direct to alternating current, which is what goes into the grid.

According to the project's Certificate of Public Good and the lease contract between Sky Solar and the District, the solar array must go online by June 30, 2018.

Special care

The land the array will sit on - 17 acres of capped garbage dump - requires special care. The landfill's cap, made of many feet of special soil and clay, must not be disturbed. To achieve this, Evans Construction's fleet has a unique feature: Trucks traveling off the access roads run on tracks, like those on a tank, rather than wheels. This helps evenly distribute the vehicle's weight.

Another challenge posed by the capped landfill is how to secure the base of the solar panels. Unlike at other solar arrays, the concrete ballast blocks cannot go into the ground.

“There is no excavation at this site,” noted WSWMD Executive Director Bob Spencer.

The property's steep banks are another tricky consideration. Sited on land overlooking the Connecticut River valley, the capped landfill follows a set of natural terraces formed when the glacier ice melted about 12,000 years ago.

To maintain stability, engineers designed the array to site panels only where the grade is less than 12 percent.

Even though the site demands creativity and extra effort in its design and implementation, solar engineers and other interested parties consider putting arrays on capped landfills a good idea.

When net-metering became available in Vermont, many residents and officials raised concerns about the siting of solar arrays. Solar panels, like prime agricultural land, do best with maximum exposure to sunshine.

Thus, the state was losing actual or potential farmland to solar arrays, and many were concerned it would get worse. In response, the Legislature and the Public Utility Commission established incentives for siting arrays on land unsuitable for farming, such as gravel pits and landfills.

Encore Renewable Energy, the project developer, noted in its presentation on the plans, the WSWMD's property is “one of Vermont's largest 'solar feasible' landfills.”

Another upside to putting a solar array on the town's former garbage dump is aesthetic. As Spencer explained during the CPG process with the state, the project's effect on the look of the surroundings is an important consideration. This array, located in an industrial part of town, “is not visible from anywhere in Vermont, except the railroad tracks, and maybe one small part from [Interstate] 91,” Spencer said.

Spencer noted this solar project is a boon for the town, the region, the net-metering customers, and the District.

Local contractors like Evans and their staff benefit from the project, which takes place during the winter, when construction projects are less frequent.

In addition, the work uses gravel from the Renaud Brothers gravel pit, barely two miles from the site.

Economic relief

Brattleboro's taxpayers will see some economic relief from the solar array. Being unsuitable for development or agriculture, a capped landfill has little economic use, and its value on Brattleboro's Grand List is limited.

But by producing energy, that 17-acre parcel rises in value, and the town can tax it at a higher rate, which then helps stabilize property taxes for homeowners and other businesses owning land in town.

Other towns and schools will see savings by participating in the solar array.

In the net-metering program, customers earn credits to use against their Green Mountain Power bill by sending electricity - in this case, solar - into the grid.

Encore, the project developer, worked with all of the array's 17 contracted customers, or “off-takers.” Of the 5 megawatts produced, the Town of Brattleboro and the Brattleboro Union High School will take nearly 2 megawatts per year.

Other big customers include the Brattleboro Retreat, Landmark College, and Marlboro College. Schools and municipalities in Wilmington, Vernon, Putney, Readsboro, Dummerston, Guilford, Wardsboro, Newfane, and Halifax have also signed contracts to participate in the net-metered project.

Jesse Stowell, director of business development at Encore, told The Commons that based on Brattleboro Union High School's previous usage, “We estimate that [BUHS] will save just under $70,000 in the first 12 months after project commissioning. The projected average annual savings is $91,863 over the 20-year contract term. That projection includes an assumption that utility rates escalate at 2.5 percent per year.”

'A nice win-win'

“There's value coming back to the District already,” Spencer said.

As soon as the facility starts generating electricity, Sky Solar will begin paying rent to the District. This allows the District to monetize an otherwise moribund 17-acre piece of land. In addition, as a net-metering off-taker, the District will earn credits on its Green Mountain Power bill.

This revenue helps stabilize the assessment its 17 member-towns pay to keep the District running, which means tax savings for residents of the member-towns.

The District is also making money selling Evans Construction the compost it makes out of household and commercial organic waste. “We sold them 300 cubic yards, for $6,000-$7,000, for revegetating the disturbed areas, which is part of our CPG and storm-water permit,” Spencer said.

“That was a nice win-win. It's a benefit for the District, and we saved them from having to drive somewhere else to get it,” Spencer said, and added, “We gave them the wholesale rate."

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