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Millstone nuclear power plant

Millstone nuclear power plant is a nuclear power station in United States with 2 operating units totalling 2,198 MW gross. The site has 3 units on record in total.

Operating2Retired4circle area ∝ site capacity Coastlines, borders and lakes: Natural Earth (1:10 million, public domain), which is generalised, so a coastal plant can sit a couple of kilometres off its true shoreline. Site positions: Global Nuclear Power Tracker.
Units on record
3
Operating
2
Operating capacity
2,198MW

Units

UnitStatusTypeModelGross MWOnline
Unit 2 Operating PWR CE 2LP (DRYAMB) 918 1975
Unit 3 Operating PWR WH 4LP (DRYSUB) 1,280 1986
Unit 1 Retired BWR - 684 1971

Unit by unit

Each unit's rating, type and milestone dates as recorded by the Global Nuclear Power Tracker, with any correction we made to it. A dash or "not disclosed" means the source does not give the value.

Millstone nuclear power plant 2 Operating

Reactor typePressurised water reactor (PWR)
ModelCombustion Engineering 2-loop
Size classLarge
Gross capacity918MW
Net capacity869MW
Thermal output2,700MWt
Enrichment3–5% U-235
NSSS vendorCombustion Engineering
OwnerDominion Resources Inc100%
OperatorDominion Energy
Construction start1 Nov 1969
First criticality17 Oct 1975
Grid connection9 Nov 1975
Commercial operation26 Dec 1975

Live status, outage record and fuel chain for Millstone nuclear power plant 2

Millstone nuclear power plant 3 Operating

Reactor typePressurised water reactor (PWR)
ModelWestinghouse 4-loop
Size classLarge
Gross capacity1,280MW
Net capacity1,210MW
Thermal output3,650MWt
Enrichment3–5% U-235
NSSS vendorWestinghouse Electric Company
OwnerDominion Resources Inc100%
OperatorDominion Energy
Construction start9 Aug 1974
First criticality23 Jan 1986
Grid connection12 Feb 1986
Commercial operation23 Apr 1986

Live status, outage record and fuel chain for Millstone nuclear power plant 3

Millstone nuclear power plant 1 Retired

Reactor typeBoiling water reactor (BWR)
Modelnot disclosed
Size classLarge
Gross capacity684MW
Net capacity641MW
Thermal output2,011MWt
Enrichment3–5% U-235
NSSS vendornot on record
OperatorDominion Energy
Construction start1 May 1966
First criticality26 Oct 1970
Grid connection29 Nov 1970
Commercial operation1 Mar 1971
Permanent shutdown1 Jul 1998

Millstone nuclear power plant in context

By gross operating capacity Millstone nuclear power plant is the 20th largest of 54 operating nuclear sites in the United States, holding 2% of the country's operating capacity, and ranks 76th of 172 worldwide.

Its operating units started up between 1975 and 1986; the median unit is 45.5 years old, older than the median of 45.0 in the United States.

The 3 units with both construction and grid dates on record took 4.6 to 11.5 years (median 6.0) from construction start to grid connection; the median across all reactors connected in the 1970s is 5.4 years.

The nearest other tracked nuclear sites are Seabrook nuclear power plant (207 km).

2 operating units are rated differently now from their design net capacities: Unit 2 -0.1% and Unit 3 +4.4%.

Build time by unit

UnitConstruction startGrid connectionYearsFleet median, same decade
Unit 1196619704.65.4 (1970s)
Unit 2196919756.05.4 (1970s)
Unit 31974198611.57.3 (1980s)

Nearest tracked nuclear sites

SiteCountryDistanceOperating GW gross
Seabrook nuclear power plantUnited States207 km1.3

How these are worked out: ranks use gross operating capacity; ages count from the start-up year on record, as on the age page; build times run from construction start to grid connection, as on the build-times page; ratings are the tracker's net and design net capacity, as on the uprates page. Distances are straight-line between exact positions, so a site with only an approximate position gets none. A unit missing a date or a rating is left out of the figure that needs it.

Site detail
LocationConnecticut, United States
Coordinates41.3107, -72.1677
Elevationabout 10 mabove sea level
SettingOn the sea coast, 1.2 km from the water
RegionNorthern America
Units by status
Operating: 2
Retired: 1

Elevation is read at the listed coordinates from a 30 m terrain model (SRTM 30 m). Two independent models differ by a median of 6 m across our plants and by up to about 40 m on steep or coastal ground, and a point on a shoreline can read as sea level. Distance to the water is measured to a generalised 1:10 million coastline, so a few kilometres or less is not resolved. This is context, not a design-basis or flood-risk figure.

Owners & operators
Owners
Dominion Resources Inc
Operators
Dominion Energy

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Sources

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