The owner of the coal-fired Brayton Point power plant, which was set to retire in 2017, will decide next week whether to delay closing now that the region’s power grid operator has designated the Somerset plant as a “must run” facility.
A must run designation means the grid operator, ISO New England, views the plant as needed to meet future electricity demand and avoid potential power interruptions. The designation does not require the plant to keep operating, but rather sets a deadline for the owner to decide so ISO can plan ahead.
Typically, the plant owner gets six months. But ISO, which designated the plant as must run in December, has asked the owner, Brayton Point Energy LLC, to expedite its decision as the grid operator plans for the retirements of several plants across the region, including Vermont Yankee nuclear plant in Vernon, Vt., and Salem Harbor Power Station, another coal plant, in Salem.
“Brayton has the choice at this point,” said Ray Hepper, ISO New England’s lawyer. “We don’t.”
Brayton Point Energy is the second-largest power plant in New England and largest coal-fired facility. In a filing sent to the Federal Energy Regulatory Commission Monday, the company agreed to the shortened timeline and said it would notify ISO of its decision by Jan. 29.
Pauline Rodrigues, a Somerset resident and a member of a grass-roots group that long has pushed for the plant’s eventual closure, said she has mixed feelings about allowing Brayton Point to operate beyond 2017. Brayton Point is a huge polluter, but is also the town’s biggest taxpayer.
The plant will pay the town about $7 million this year, according to a local newspaper.
“For the town’s sake, to give them time to prepare, I’m hoping that they will announce that they will remain open temporarily,” Rodrigues said. “As far as health goes, the sooner they close down, the better.”
Low prices for natural gas and increasing environmental regulations have made coal plants less economical to run. Brayton Point and Salem Harbor, long considered two of the state’s dirtiest power plants, are among the last of the large coal-burning facilities in Massachusetts. A third, Mount Tom, operates in Holyoke.
Last year, Dominion, Brayton Point’s former owner, sold the plant and two others for $472 million to Energy Capital Partners, a private equity firm with offices in California and New Jersey.
Just a few months later, the new owner announced the plant’s retirement.
Delaying the shutdown would help ensure the reliability of the regional power grid in the next few years, ISO New England says. It would remain open under a negotiated agreement with the grid operator that would subsidize the plant to keep operating.
But power industry officials worry that could distort the power market and lead to artificially low prices that would hurt other generators.
“Let’s say they accept ISO’s reliability determination and say, ‘OK, we are going to hang around,’ ” said Dan Dolan, president of the New England Power Generators Association, a trade group. “You still have these resources that are receiving, what is essentially a subsidy, undermining an otherwise competitive market.”
Environmentalists — who have long pressed for the shutdown of coal plants, one of the biggest producers of greenhouse gases that contribute to climate change — also expressed concerns about extending the life of the plant. Seth Kaplan, vice president for policy and climate advocacy at the Conservation Law Foundation in Boston, said he still expects Brayton Point to shut down in the next few years because of the economic pressures, but stressed that ISO New England needs to find ways to phase out coal while maintaining the system’s reliability.
“At the end of the day, the likelihood that any of those Brayton units will be running in  is really, really small,” Kaplan said. “Getting the rules right for leaving the market is just as important as getting the rules right for entering it.”
Region’s power plants
Plant Fuel Location Capacity (MW)
1. Mystic Generating Station Gas Charlestown 1,968
2. Brayton Point Coal Somerset 1,545
3. Canal Petroleum Sandwich 1,119
4. Northfield Mountain Hydro Northfield 1,080
5. Salem Harbor Coal Salem 744