By TIM FAULKNER/ecoRI News staff
PROVIDENCE — The Narragansett Bay Commission is making good on its promise to run on 100 percent renewable energy by 2020. The goal will be met with the addition of two proposed solar arrays, along with its existing wind turbines.
However, unlike the trio of wind turbines that spin onsite at the state’s largest wastewater treatment facility, the solar facilities will be built miles away on private land in Coventry and Richmond.
The Narragansett Bay Commission (NBC) already owns three wind turbines in Coventry built by Green Development LLC. The North Kingstown renewable-energy company, formerly Wind Energy Development LLC, built some of the state’s first wind turbines, including 10 in Coventry.
Thanks to a law passed by the General Assembly in 2016, Green Development will own the solar arrays and NBC will receive the renewable-energy credits. Known as virtual net metering, the incentive program allows people and organizations to receive the credits for renewable energy without owning the property or the energy system.
Expect to see more of these shared-power/ownership agreements now that the General Assembly opened the incentive program this year to nonprofits and educational institutions.
The solar arrays in two of the state’s more rural towns furthers the debate about the impact utility-scale renewable-energy systems have on open space. Many solar projects eliminate large tracts of woodlands, meadows and farmland. It’s common for miles of chain-link fence to surround solar fields, limiting the movement of wildlife and the hydrology of local wetlands.
Developers say the projects protect open space from permanent housing developments, commercial buildings and their related infrastructure. Solar fields, they say, don't penetrate deeply into the ground and are easy to remove. Therefore, the land can easily revert to natural habitat after a solar array's expected life of about 25 years.
Proponents say the land in and around solar arrays can be landscaped to include habitat for birds and beneficial insects, and even provide grazing for foragers.
“A solar array has little or no impact,” Cranston city planner Peter Lapolla said during a contentious debate in 2015 over a 10-acre solar array proposed for a former tree farm.
But some open-space advocates question the need to destroy woodlands and farmland and alter wetlands to make room for wind turbines and solar panels. A sea of solar panels and the interconnection equipment create a visual disturbance and generate noise from power inverters, they say.
The Land Trust Alliance, a nationwide network of land conservation groups, says communities should designate land for renewable energy and open habitat, beacause “large solar facilities dramatically alter the land. They come at a cost for wildlife habitat, farm and ranch land, scenic beauty and recreational and wilderness opportunities.”
Either way the debate over land use and renewable energy will intensify in Rhode Island. This year the General Assembly passed a law allowing up to 20 percent of farmland and protected open space to host renewable-energy projects without losing their local property-tax status.
Meanwhile, early adapters of renewable energy are seeing financial and environmental benefits. The three turbines at the NBC facility on the Providence waterfront save an estimated $1.1 million annually. NBC expects to save $18 million in energy costs over 25 years from the two solar arrays. The climate benefits will be equivalent to offsetting 110,092 metric tons of carbon dioxide.
The planned solar array in Coventry would have a capacity of 4.24 megawatts. The Richmond solar array will have a 5.45-megawatt capacity.
NBC provides sewage and wastewater treatment for 10 Rhode Island municipalities, including Providence. In addition to the wind turbines and solar arrays, NBC is building a 600-kilowatt anaerobic digester at its Bucklin Point wastewater facility in East Providence. This biogas system will burn a methane-gas mixture released during the sludge stabilization process at the wastewater treatment plant. The system is expected to be operational by next summer.