Coal-fired power in state down to embers
Environmental activists rallied outside coal-fired power plants in Somerset and Holyoke this week, calling on Gov. Deval Patrick to shut the plants down. The activists don’t necessarily need political pressure on their side, though. Coal plants across New England are struggling, and it’s the energy market, not politics, putting them on the ropes.
Coal- and oil-fired power plants were once the workhorses of the Massachusetts power plant fleet. Both fuels are heavy polluters, and both have faded to the margins. The high cost of petroleum has virtually eliminated oil-fired electricity in Massachusetts, while competition from natural gas has thrown the economics of coal-fired generation upside down. The coal plants are expensive to operate and maintain, and they’re only running at a fraction of their capacity.
Power plants in Massachusetts bid to sell electricity into the power grid. The grid’s operator, ISO New England, calculates how much electricity the region will need on a given day, starts with the lowest-priced power, and then works up the auction until reaching that day’s quota. Coal-fired plants had, historically, produced the cheapest electricity. A sharp drop in natural gas prices, however, has left the coal plants unable to compete. The fuel that runs coal plants still comes more cheaply than gas, but coal plants are far more expensive to run; the cost of operating older, less efficient, and far dirtier facilities has pushed the cost of coal-fired electricity above the gas plants. Unable to compete on price, the coal plants are now only running when demands on the grid max out.
The drop in production looks especially troublesome for Brayton Point. The plant’s owner, Dominion, has invested more than $1 billion in the coal plant since buying the facility in 2005. Those investments include two new massive cooling towers to comply with clean water regulations, as well as air pollution controls. The Conservation Law Foundation says generators at Brayton Point are now running at between 10 percent and 25 percent of their capacity. Shanna Cleveland, a staff attorney at CLF, says that’s unsustainable. “It’s really difficult for a facility of that size, with that number of staff, and the investments they’ve made in pollution control, to remain economic when operating [part-time],” she says.
The slowdown at the Somerset and Holyoke coal plants follows financial turmoil at the coal-fired plant in Salem.
Dominion recently sold its other Massachusetts coal-fired power plant at Salem Harbor after running into economic difficulties. Even without the costly environmental infrastructure installed at Brayton, Salem’s electricity prices were consistently among the state’s highest. Unable to compete with gas, Dominion mothballed two Salem generators at the end of 2011, and agreed to close the entire plant shortly thereafter. Salem Harbor’s new owner will redevelop the plant as a gas-fired facility. Dominion did not return calls for comment.
In 2000, coal accounted for 29 percent of state’s electric supply, and 43 percent of electric generators’ carbon dioxide emissions; by 2010, coal was fueling just 19 percent of the state’s electricity, but still accounting for 43 percent of the industry’s carbon dioxide emissions. During the same period, petroleum-fired electric plants all but disappeared, while the share of gas-fired electricity more than doubled, from 28 percent of the state’s production, to 60 percent.
The rise of gas and the decline of coal and oil has dovetailed with a sharp drop in carbon emissions: While Massachusetts power plants increased their output by 11 percent over the past decade, carbon emissions dropped by 18 percent.
Salem Harbor, Brayton Point, and Mount Tom comprise three-fifths of the Filthy Five, a group of coal- and oil-fueled plants that once produced the vast majority of the state’s air pollution. Canal Station in Sandwich and Mystic Generating Station in Charlestown rounded out the group.
As recently as 2009, the Filthy Five contributed 70 percent of the Massachusetts energy industry’s carbon dioxide emissions. But all five have been pressured by competition from natural gas, and by the cost of pollution mitigation. RGGI data show Canal Station saw its hours of operation fall by 87 percent between 2009 and 2011. Mystic has shut down older generators and repositioned itself as a natural gas-burning plant.