Millstone
Nuclear power plant · New London County, Connecticut
Details
- Primary fuel
- Nuclear
- Technology
- Nuclear
- Operator
- Dominion Energy Nuclear Conn Inc
- County
- New London County
- Generating units
- 2
- Share of state capacity
- 20.55%
- Rank among nuclear plants in Connecticut
- #1 of 1
- EIA plant code
- 566
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 3 | Nuclear | 1,350 MW | 1,245 MW | 1986 | Operating |
| 2 | Nuclear | 910 MW | 863 MW | 1975 | Operating |
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 Connecticut
| CPV Towantic Energy Center | Natural gas | 842 MW |
| Lake Road Generating Plant | Natural gas | 840 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 2,260 MW solar plant and a 2,260 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 Connecticut power plants · What Connecticut actually generates