Electric power plants in Greater Boston may experience fuel shortages this summer because exports from Yemen, a major supplier of natural gas, have been disrupted by attacks by militants, energy officials said Friday.

No shortages or outages are imminent, but officials are developing contingencies in case a heat wave drives up electricity use or a local power plant has an unexpected outage.

Natural gas is the dominant source of fuel for New England’s power plants, and about 25 percent of that is liquefied gas that is shipped, mostly from Yemen and the Caribbean, to three local terminals, according to federal energy and industry sources.


Two tankers-worth of gas from Yemen that were bound for a terminal in Everett - one to arrive this month and another in June - never sailed because of the attacks in Yemen, according to the terminal’s owner, Distrigas of Massachusetts LLC. Yemen’s pipelines have been under attack since antigovernment protests began last year, according to news accounts; in the most recent, an armed group affiliated with Al Qaeda claimed responsibility for bombing a pipeline in retaliation for the killing of an Al Qaeda leader.

While the Everett terminal gets natural gas deliveries from elsewhere, the lost Yemen supplies could cause problems for those power plants that depend on liquefied natural gas. That includes Mystic generating station in Charlestown, which Distrigas said supplies 30 percent of Greater Boston’s power and relies on the Everett terminal for its natural gas.

“We expect it to impact about 20 percent of our LNG deliveries,’’ said Kevin Thornton, a spokesman for Exelon Corp., which owns the Mystic facility. Still, he expected the plant to continue producing electricity without interruption.

Distrigas said it is working with its largest liquefied natural gas supplier in Trinidad and Tobago for additional supplies should there be more disruptions in Yemen.


It has also arranged to deliver some natural gas by pipeline to customers.

Thomas M. Kiley, president of the Northeast Gas Association, said members of his organization are watching the situation in Yemen closely, but “at this juncture, we are not hearing any alarm from any of our member companies.’’

The operator of the regional power grid, ISO New England, said Friday it is working with government officials to respond if there is a shortage.

Plans include suspending scheduled maintenance on the power transmission network, and invoking demand response resources, which pay customers to reduce their energy use at times of peak demand, said ISO New England spokeswoman Ellen Foley.

“My understanding is that under normal weather conditions or normal operating conditions, this won’t be an issue,’’ Foley said.

“This is an unusual occurrence, but it’s always something that we have to prepare to manage through.’’

State energy officials confirmed that they are coordinating with ISO, as well as local regulators and others, to locate replacement sources of energy in case of shortages.

One possibility includes finding a way to quickly hook renewable power supplies, such as solar panels, into the grid.

Erin Ailworth can be reached at eailworth@globe.com. Follow her on Twitter @ailworth.