The state Public Service Commission this week granted a request by National Grid to increase the maximum output of two sets of peak-power generators, in Port Jefferson and Glenwood Landing.

The plants, which provide power primarily during peak-use periods in the summer, have been limited under state rules to produce a total of 79.9 megawatts each, even though they are technically capable of up to 94 megawatts. A megawatt powers up to 1,000 homes. The PSC ruling allows the plants, which consist of two sets of natural-gas powered turbines, to operate at their maximum outputs.

The commission found that there would be “no significant environmental impacts” to increasing the power output of the plants, given that the only alteration required was software used at the facility. The PSC noted that it had already granted similar requests for peaking plants in Shoreham and Edgewood, which increased their output to 95 megawatts from 79.9 megawatts. The restrictions had been imposed by the Article X siting law, which it said had expired.

The ruling noted objections during public hearings last March, including concerns that increasing the output of the smaller plants could hasten the closure of the larger Port Jefferson power station.

Port Jefferson’s Deputy Mayor Larry LaPointe in March accused LIPA of “increasing their ability to shut down the main plant in Port Jefferson” by drawing more power from the smaller units, since the larger plant is used less than 10 percent of the year. The PSC ruling noted, “Whether the Port Jefferson Power Plant closes is beyond the scope of this proceeding.”

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Separately on Wednesday, PSEG Long Island said it was activating a program that allows it to lower peak power use by remotely adjusting the air-conditioning units of 35,000 participating customers. The program was implemented between 4 p.m. and 6 p.m., on Wednesday, and is expected to be activated from 2 p.m. to 6 p.m. on Thursday and Friday.

PSEG said activating the program will cut 34 megawatts from capacity requirements next year, for a savings of around $2.2 million. Last year, it saved $2 million, PSEG said. Customers with central air conditioners who participate in the plan experience 30 minute on- and off-cycling of their systems or a four-degree increase in temperature setting, PSEG said.