Millstone

⚛ NuclearIPP Non-CHP2,259 MW capacity

1st largest plant in Connecticut · 58th nationally

Millstone is a nuclear power plant in Connecticut with a nameplate capacity of 2,260 MW. It generates roughly 13.7M MWh per year — enough to power about 1,301,853 average U.S. homes.

Its capacity factor of 69% puts it in the middle range — running steadily but not full-time.

PeakingMid-meritBaseload0%40%80%100%69%
Mid-merit — steady but not full-time
Capacity2,260 MWnameplate
Annual Generation13.7M MWhEPA eGRID
Capacity Factor69%of theoretical max
Annual CO₂metric tons

Location

Plant NameMillstone
OperatorDominion Energy Nuclear Conn Inc
CityWaterford
CountyNew London County
StateConnecticut
ZIP06385
Coordinates41.31070, -72.16770

This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.

NuclearNatural GasOilHydroelectricSolarBiomass

Generators (2)

IDTechnologyFuelCapacityStatusOnline
3NuclearUranium1,350 MWOperating1986
2NuclearUranium910 MWOperating1975

Ownership

OwnerLocationShare
Dominion Energy Nuclear Conn IncWaterford, CT9347.0%
Massachusetts Mun Wholes Electric CoLudlow, MA480.0%
Green Mountain Power CorpColchester, VT173.0%

Ownership reported to EIA Form 860. Percentages reflect reported generator-level ownership share, averaged when a plant has multiple generators.

Grid context

NERC RegionNPCC
Balancing AuthorityIso New England Inc.

About Nuclear plants

Nuclear plants generate carbon-free baseload electricity by fissioning uranium fuel inside a reactor. They run nearly around-the-clock — typical capacity factors above 90% — and a single facility can power millions of homes. Spent fuel is stored on-site in dry casks. NRC oversees safety; emergency planning zones extend 10 miles from the reactor.

Other plants in New London County

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