1235.8 MW Nuclear operating in Callaway, MO — Midcontinent Independent Transmission System Operator, Inc..
1,235.8 MW
Nameplate Capacity
1
Generators
unit
Nuclear
Technology
1984
Operating Since
Coordinates
38.7589, -91.7788
County
Callaway, MO
Nearby Plants
Owner data does not fully agree across sources.
EIA typically reports the operating utility, while GEM resolves to the financial owner or parent corporation. Both can be correct.
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Union Electric Co - (MO) | Ameren UE; Union Electric | Ameren Missouri |
| Owner(s) | Union Electric Co - (MO) | Ameren UE; Union Electric Co [100%] | — |
| Status | Operating | operating | — |
GEM identifies the owner as Ameren UE; Union Electric Co [100%]
This entity is not yet in the GEM ownership database — chain unavailable.
The Callaway Plant is a nuclear power plant located in Callaway County, Missouri. The plant is Missouri's only nuclear power plant and is close to Fulton, Missouri. The 2,767 acres (1,120 ha) site began operations on December 19, 1984. It generates electricity from one 1,190-megawatt Westinghouse four-loop pressurized water reactor and a General Electric turbine-generator. The Ameren Corporation owns and operates the plant through its subsidiary Ameren Missouri. It is one of several Westinghouse reactors designs called the "Standard Nuclear Unit Power Plant System," or SNUPPS.
Read more on WikipediaCallaway is a 1,235.8 MW nuclear power plant located in Callaway County, Missouri. The plant, which began operating in 1984, is owned and operated by Union Electric Co. The facility consists of a single nuclear generator. Callaway is the largest nuclear power plant in Missouri, and ranks 39th out of 55 nuclear plants nationally.
The plant's latest annual generation was 7,116,161 MWh, resulting in a capacity factor of 65.6%. Callaway operates within the Midcontinent Independent Transmission System Operator (MISO) balancing authority and the SERC NERC region. Financial data indicates an installed cost of $2,541.08 per kW, based on FERC data.
Generated from EIA, GEM, and public data sources
NERC Region
SERC
Balancing Authority
Midcontinent Independent Transmission System Operator, Inc..
Grid Voltage
345 kV
Regulatory Status
RE
Entity Type
Investor-Owned Utility
Sector
Electric Utility
883.6K MWh
Latest Month
7.1M MWh
Annual Generation
65.6%
Capacity Factor
$2,960/kW
Installed Cost
$21.4/MWh
Operating Cost
UNION ELECTRIC COMPANY
Reporting Utility
Annual Capital & Operating Expenses
Cumulative Installed Cost
Per-Unit Cost Trends
Point of Interconnection
Nearest Substation
Callaway Substation · 345 kV
Substation Distance
< 10 km
Operator
Ameren
Coord Source
OSM spatial
Market Position
ISO/RTO Market
MISO
LMP Node
AMMO.CALLAWAY1
Pricing Hub
ILLINOIS.HUB
Location Type
Generation Node
Node Source
EIA-860 direct report
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