451 MW Conventional Steam Coal (450 MW) + Petroleum Liquids (1 MW) operating in Grant, SD — Midcontinent Independent Transmission System Operator, Inc..
451 MW
Nameplate Capacity
2
Generators
units
Hybrid (2)
Technology
Conventional Steam Coal + Petroleum Liquids
1975
Operating Since
Coordinates
45.3037, -96.5101
County
Grant, SD
Nearby Plants
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Otter Tail Power Co | Montana-Dakota Utilities | — |
| Owner(s) | Montana-Dakota Utilities Co, NorthWestern Energy - (SD), Otter Tail Power Co | small shareholder(s) | — |
| Status | Operating | — | — |
Big Stone is a 451 MW hybrid power plant located in Grant County, South Dakota. The plant began operating in 1975 and is operated by Otter Tail Power Co. While the primary fuel is listed as DFO (distillate fuel oil), the plant utilizes both conventional steam coal and petroleum liquids as energy sources. Big Stone is the largest of three power plants in South Dakota and ranks 26th out of 60 nationally. The plant consists of two generators.
Big Stone operates within the Midcontinent Independent Transmission System Operator, Inc. balancing authority and the MRO NERC region. The latest annual generation data indicates an output of 2,029,575 MWh, achieving a capacity factor of 51.4%. Ownership is attributed to small shareholder(s).
Generated from EIA, GEM, and public data sources
NERC Region
MRO
Balancing Authority
Midcontinent Independent Transmission System Operator, Inc..
Grid Voltage
230 kV
Regulatory Status
RE
Entity Type
Investor-Owned Utility
Sector
Electric Utility
191.6K MWh
Latest Month
2.0M MWh
Annual Generation
51.4%
Capacity Factor
No financial data available for this plant.
Point of Interconnection
Nearest Substation
Big Stone Substation · 230 kV
Substation Distance
< 10 km
Coord Source
OSM spatial
Market Position
ISO/RTO Market
MISO
LMP Node
OTP.BIGSTON1
Pricing Hub
MINN.HUB
Location Type
Generation Node
Node Source
EIA-860 direct report
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