SOMERSET -- Brayton Point -- the largest coal-fired power plant in New England and the last remaining coal plant in Massachusetts -- will close for good as of June 1, owner Dynegy announced Monday.

The decision to close the 1,500-megawatt plant was made by former owner Energy Capital Partners in January 2014. The private equity firm had failed to secure an agreement with ISO New England, the operator of the six-state power grid, the Providence Journal reported at the time.

The closure decision came months after ECP agreed to pay the Virginia-based Dominion $650 million for Brayton Point and two power plants in Illinois.

Located in Somerset on Mount Hope Bay, Brayton Point's concrete cooling towers form a distinctive landscape element along the Southeastern Massachusetts shoreline near Fall River. The plant's four generators, when firing at full capacity, can power 1.5 million homes.

Dominion owned the 1960s-vintage plant from 2005 to 2013, and invested more than $1 billion in pollution control technology before market and regulatory forces undermined the facility's profitable operation. The plant started operating less and less often.

Environmental and public health advocates, including the Conservation Law Foundation, had long called for the plant's closure, once identified as a leading source of air pollution in New England.

Coal-fired plants are shutting down around the country, faced with the high cost of running aging facilities, air pollution disincentives, state policies favoring renewables, and competition from natural gas generators.

Coal currently generates a little more than 2 percent of the region's power mix, according to ISO New England, which projects major coal, oil, and nuclear power plant retirements in the coming years.

Dynegy in February acquired a portfolio of U.S. power generators owned by ENGIE, the French energy firm, in a $3.3 billion deal. The company now runs 50 power plants totaling 31,000 megawatts, enough to power 25 million homes, including four natural gas plants in Massachusetts.



Mary Serreze can be reached at mserreze@gmail.com