Merrimack

Coal power plant · Merrimack County, New Hampshire

Nameplate capacity
496 MW
Rank in New Hampshire
#4
of 61 plants
In service since
1960
December 1960

Details

Primary fuel
Coal
Technology
Conventional Steam Coal
Operator
Granite Shore Power
County
Merrimack County
Generating units
4
Share of state capacity
10.83%
Rank among coal plants in New Hampshire
#1 of 1
EIA plant code
2364

Generating units

Individual generating units at Merrimack
UnitTechnologyNameplateSummerOnlineStatus
2Conventional Steam Coal346 MW331 MW1968Out of service and NOT expected to return to service in next calendar year
1Conventional Steam Coal114 MW108 MW1960Operating
GT1Petroleum Liquids19 MW17 MW1968Operating
GT2Petroleum Liquids19 MW17 MW1969Operating

Nameplate is the maximum rated output; summer capacity is what the unit can reliably deliver on a hot day, which is typically lower.

Similarly sized plants in New Hampshire

Granite RidgeNatural gas790 MW
Newington Energy CenterNatural gas606 MW
NewingtonOther414 MW
S C MooreHydro195 MW

About this data

From EIA’s inventory of operable generators, May 2026 release. Capacity is nameplate — the maximum rated output of the equipment, not what the plant actually generates over a year, which depends on how often it runs. A 496 MW solar plant and a 496 MW nuclear plant have the same entry here and produce very different amounts of electricity.

“In service since” is the earliest in-service date among the units still listed, so a site rebuilt around newer equipment can read as younger than the site itself. All New Hampshire power plants · What New Hampshire actually generates