# Comanche Peak

ERCOT Nuclear · https://askthegrid.com/ercot/assets/plant/comanche-peak

Comanche Peak is a two-unit nuclear power plant in Somervell County, Texas, with 2,400 MW of EIA-reported net summer capability. Its Westinghouse four-loop pressurized-water reactors entered commercial service in 1990 and 1993 and map to ERCOT resources CPSES_UNIT1 and CPSES_UNIT2.
ERCOT maps the plant's two operating units to CPSES_UNIT1 and CPSES_UNIT2.

## Key facts

- Technology: Nuclear
- Power capacity: 2400 MW
- Operating status: operating

## Grid and market context

- ISO/RTO: ERCOT
- Balancing authority: ERCOT
- Settlement node: CPSES_UNIT1
- Market resources: CPSES_UNIT1, CPSES_UNIT2

## Settlement price economics

Observed ERCOT settlement prices at CPSES_UNIT1, 2025-07-26 to 2026-07-25 (364 days, 8,732 settled hours).

- Average price: $29.54/MWh
- Hourly range: -$218 to $1,256/MWh
- Negative price hours: 385
- TB2 spread benchmark: $48.0/kW-yr
- Average daily top/bottom spread: $65.93/MWh

The TB2 figure is a price benchmark, not revenue. It values one perfect-foresight cycle per day, gross of round-trip losses, and excludes ancillary services. It is not this asset's realized capture and assumes no dispatch.

## Timeline

- 1974-12-19 — Construction started
  IAEA PRIS records December 19, 1974 as the construction start date for both units.
  Source: IAEA PRIS: Comanche Peak Unit 1 (https://pris.iaea.org/pris/CountryStatistics/ReactorDetails.aspx?current=729)
- 1990-08-13 — Unit 1 commercial operation
  Comanche Peak Unit 1 entered commercial operation.
  Source: IAEA PRIS: Comanche Peak Unit 1 (https://pris.iaea.org/pris/CountryStatistics/ReactorDetails.aspx?current=729)
- 1993-08-03 — Unit 2 commercial operation
  Comanche Peak Unit 2 entered commercial operation.
  Source: IAEA PRIS: Comanche Peak Unit 2 (https://pris.iaea.org/PRIS/CountryStatistics/ReactorDetails.aspx?current=730)
- 2015-07-22 — Fluor maintenance contract announced
  Fluor announced a five-year contract covering engineering, maintenance and modifications, and facility services.
  Source: Fluor maintenance-services announcement (https://newsroom.fluor.com/news-releases/news-details/2015/Fluor-Awarded-Power-Maintenance-Services-Contract-for-Luminants-Comanche-Peak-Nuclear-Plant/default.aspx)
- 2025-09-29 — 1,200 MW power agreement announced
  Vistra announced a 20-year agreement for 1,200 MW from Comanche Peak. Delivery is expected to begin in the fourth quarter of 2027 and ramp to full capacity by 2032; the filing did not initially name the customer.
  Source: Vistra Corp. Form 8-K (https://www.sec.gov/Archives/edgar/data/1692819/000119312525221774/d43667d8k.htm)
- 2026-02-26 — Vistra identified AWS as the power customer
  Vistra identified Amazon Web Services as the customer under the previously announced 1,200 MW agreement; this was a customer disclosure, not a second PPA.
  Source: Vistra 2025 results (https://investor.vistracorp.com/2026-02-26-Vistra-Reports-Fourth-Quarter-and-Full-Year-2025-Results)

## Sources

- [EIA Form 860](https://www.eia.gov/electricity/data/eia860/) — eia.gov · tier government
- [ERCOT settlement point mapping](https://www.ercot.com/misapp/GetReports.do?reportTypeId=10008&reportTitle=Settlement%20Points%20List%20and%20Electrical%20Buses%20Mapping&showHTMLView=&mimicKey) — ercot.com · tier government
- [Comanche Peak Unit 1](https://www.nrc.gov/info-finder/reactors/cp1) — nrc.gov · tier government
- [IAEA PRIS: Comanche Peak Unit 1](https://pris.iaea.org/pris/CountryStatistics/ReactorDetails.aspx?current=729) — iaea.org · tier government
- [IAEA PRIS: Comanche Peak Unit 2](https://pris.iaea.org/PRIS/CountryStatistics/ReactorDetails.aspx?current=730) — iaea.org · tier government
- [Vistra Corp. Form 8-K](https://www.sec.gov/Archives/edgar/data/1692819/000119312525221774/d43667d8k.htm) — sec.gov · tier filing
- [Fluor maintenance-services announcement](https://newsroom.fluor.com/news-releases/news-details/2015/Fluor-Awarded-Power-Maintenance-Services-Contract-for-Luminants-Comanche-Peak-Nuclear-Plant/default.aspx) — fluor.com · tier company
- [EPA ECHO facility record](https://echo.epa.gov/detailed-facility-report?fid=TX0065854) — epa.gov · tier government
- [TxGIO land parcel service](https://feature.geographic.texas.gov/arcgis/rest/services/Parcels/stratmap_land_parcels_48_most_recent/MapServer) — texas.gov · tier government

## Data quality

- Capacity, reactor design, commercial-operation dates, license terms, ownership, operation, market resources, permits, and the power agreement were checked against EIA, ERCOT, NRC, IAEA PRIS, SEC, EPA, TCEQ, and official company records.

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Canonical page: https://askthegrid.com/ercot/assets/plant/comanche-peak
Profile published: 2026-07-17T03:34:09.577Z
Source: Ask the Grid — https://askthegrid.com/