249 MW Conventional Steam Coal (99 MW) + Natural Gas Fired Combustion Turbine (150 MW) operating in Williamson, IL — Midcontinent Independent Transmission System Operator, Inc..
249 MW
Nameplate Capacity
5
Generators
units
Hybrid (2)
Technology
Conventional Steam Coal + Natural Gas Fired Combustion Turbine
1963
Operating Since
Coordinates
37.6176, -88.9569
County
Williamson, IL
Nearby Plants
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Southern Illinois Power Coop | — | — |
| Owner(s) | Southern Illinois Power Coop | — | — |
| Status | Operating | — | — |
The Marion power plant, located in Williamson County, Illinois, has a total capacity of 249 MW. The plant began operating in 1963 and is owned and operated by Southern Illinois Power Coop. The primary fuel source is bituminous coal (BIT), and the plant utilizes conventional steam coal technology, along with natural gas fired combustion turbine technology, classifying it as a hybrid plant. Marion consists of 5 generators.
In the most recent year with available data, the plant generated 767,048 MWh, operating at a capacity factor of 35.2%. Marion operates within the Midcontinent Independent Transmission System Operator, Inc. (MISO) balancing authority and the SERC NERC region. The plant is ranked 3 out of 4 among similar plants in Illinois and 46 out of 50 nationally.
Generated from EIA, GEM, and public data sources
NERC Region
SERC
Balancing Authority
Midcontinent Independent Transmission System Operator, Inc..
Grid Voltage
161 kV
Regulatory Status
RE
Entity Type
Cooperative
Sector
Electric Utility
74.0K MWh
Latest Month
767.0K MWh
Annual Generation
35.2%
Capacity Factor
No financial data available for this plant.
Market Position
ISO/RTO Market
MISO
LMP Node
SIPC.MARIOGEN5
Pricing Hub
ILLINOIS.HUB
Location Type
Generation Node
Node Source
EIA-860 direct report
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