# Marion

MISO asset profile · https://askthegrid.com/assets/facilities/marion

## Current generation inventory

EIA plant 976 · Inventory reporting month: 2026-08.

- coal: 99 MW operating nameplate
- natural gas: 150 MW operating nameplate
- Capacity basis: operating_generator_nameplate_mw
- Source inventory: [EIA-860M workbook (preliminary)](https://www.eia.gov/electricity/data/eia860m/xls/august_generator2026.xlsx)
- Inventory retrieved: 2026-10-10T02:12:40.665346+00:00
- Filed coordinate (longitude, latitude): -88.95311, 37.619747
- OSM extract: 2026-10-08T20:21:06Z
- OSM mapped edit: 2022-08-01 18:48:12+00:00
- Map prepared: 2026-10-10T02:28:21.792931+00:00

Battery power (MW) and stored energy (MWh) are separate measures. Shared physical-site membership does not establish electrical connectivity, settlement or a common export limit.

## Reviewed overview

The Marion plant near Marion in Williamson County, Illinois, is owned by Southern Illinois Power Cooperative, a generation and transmission cooperative. Its generation today is a 120 MW coal-fired circulating fluidized bed boiler and two 70 MW simple cycle combustion turbines burning natural gas or oil. GE Frame 7EA turbines entered commercial operation in 2003 as peaking capacity. In 2020 the cooperative's board approved a plan to retire the larger coal-fired Unit 4.

## Reviewed metrics

- **Nameplate capacity:** 249 MW — Canonical EIA plant baseline.
- **Registry anchor:** Plant 976 — plant-976

## Facts

- **Technology:** Conventional Steam Coal, Natural Gas Fired Combustion Turbine
- **Operator:** Southern Illinois Power Cooperative

## Related parties

- **Owner / operator:** Southern Illinois Power Cooperative — owner ([source](https://www.sipower.org))
- **EPC contractor:** Sargent & Lundy — epc_contractor ([source](https://www.sargentlundy.com))
- **Equipment supplier:** GE Power Systems — equipment_supplier

## Sources

- [icl.coop](https://icl.coop/sipc-approves-plan-to-retire-unit-4-operation/) — icl.coop · public_source — Source retained for exact-record publication review.
- [industrialinfo.com](https://www.industrialinfo.com/news/article/southern-illinois-power-cooperative-completes-additions-to-marion-power-station--26769) — industrialinfo.com · public_source — Source retained for exact-record publication review.

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Canonical page: https://askthegrid.com/assets/facilities/marion
Website: [Southern Illinois Power Cooperative](https://www.sipower.org)

Source: Ask the Grid — https://askthegrid.com/