# Nine Mile Point Nuclear Station NYISO nuclear_power_plant · https://askthegrid.com/nyiso/assets/plant/nine-mile-point-nuclear-station Two-unit nuclear generating station located at 348 Lake Road in Oswego, New York, on the shores of Lake Ontario. Unit 1 (613 MW, GE BWR-2) entered commercial operation on December 1, 1969. Unit 2 (1,277 MW, GE BWR-5) entered commercial operation on March 11, 1988. Constellation Energy owns Unit 1 (100%) and 82% of Unit 2; Long Island Power Authority owns the remaining 18% of Unit 2. Constellation operates the plant. The facility interconnects to the New York State Transmission System at the Scriba Substation at 345 kV. Unit 1 is currently licensed through August 22, 2029 and has a pending subsequent license renewal application; Unit 2 is licensed through 2046. ## Key facts - Technology: Nuclear - Power capacity: 1901.1 MW ## Grid and market context - ISO/RTO: NYISO - Balancing authority: NYISO ## Source-backed facts - Location.county: Oswego — constellationenergy.com · confidence: review_required - Location.state: New York — constellationenergy.com · confidence: review_required - Location.address: 348 Lake Road, Oswego, New York 13126 — constellationenergy.com · confidence: review_required - Site.acres: 900 acres — federalregister.gov · confidence: review_required - Capacity.total mw: 1907 MW — constellationenergy.com · confidence: review_required - Unit.1.capacity mw: 613 MW — gevernova.com · confidence: review_required - Unit.2.capacity mw: 1277 MW — gevernova.com · confidence: review_required - Operations.capacity factor 2025: 95.6 percent — constellationenergy.com · confidence: review_required - Operations.generation 2025 mwh: 13965000 MWh — constellationenergy.com · confidence: review_required - Operations.employees: 827 — constellationenergy.com · confidence: review_required - Operations.annual taxes usd millions: 30.9 millions USD — constellationenergy.com · confidence: review_required ## Timeline - 1965-04-12 — Unit 1 construction began Construction began for Nine Mile Point Unit 1 Source: en.wikipedia.org (https://en.wikipedia.org/wiki/Nine_Mile_Point_Nuclear_Generating_Station) - 1969-12-01 — Unit 1 commercial operation Unit 1 entered commercial operation Source: en.wikipedia.org (https://en.wikipedia.org/wiki/Nine_Mile_Point_Nuclear_Generating_Station) - 1975-08-01 — Unit 2 construction began Construction began for Nine Mile Point Unit 2 Source: en.wikipedia.org (https://en.wikipedia.org/wiki/Nine_Mile_Point_Nuclear_Generating_Station) - 1988-03-11 — Unit 2 commercial operation Unit 2 entered commercial operation Source: en.wikipedia.org (https://en.wikipedia.org/wiki/Nine_Mile_Point_Nuclear_Generating_Station) - 2000-12-13 — Constellation acquisition Constellation Nuclear finalized the purchase of the two-unit Nine Mile Point plant for $815 million including fuel Source: nucnet.org (https://www.nucnet.org/news/us-constellation-buys-nine-mile-point-for-815-million-dollars) - 2012-01-03 — Unit 2 power uprate The NRC approved a 15% Unit 2 uprate, approximately 521 MW thermal and approximately 158 MW electric Source: poweronline.com (https://www.poweronline.com/doc/nrc-approves-increased-power-output-for-nine-0001) - 2014-01-01 — Operating responsibility assigned to Exelon Generation Operating responsibility for Unit 2 was assigned to Exelon Generation, while PSEG Long Island managed LIPA's interest Source: lipower.org (https://www.lipower.org/wp-content/uploads/2019/05/2.2-Approval-Exelon-Generation-for-Nine-Mile-Point-Unit-2.pdf) - 2022-02-01 — Constellation Energy Corporation separation Constellation Energy Corporation separated from Exelon and became the stand-alone owner of Nine Mile Point Unit 1 and Unit 2 Source: nrc.gov (https://www.nrc.gov/docs/ML2513/ML25135A345.pdf) - 2026-03-25 — Unit 1 subsequent license renewal application Constellation Energy Generation submitted an application seeking an additional 20 years of Unit 1 operation Source: nrc.gov (https://www.nrc.gov/sites/default/files/cdn/doc-collection-news/2026/26-038.pdf) - 2026-04-29 — NRC accepted Unit 1 renewal application for docketing The NRC published notice that the Unit 1 subsequent-license-renewal application was acceptable for docketing; docketing was not approval of the renewed license Source: federalregister.gov (https://www.federalregister.gov/documents/2026/04/29/2026-08276/constellation-energy-generation-llc-nine-mile-point-nuclear-station-unit-1-subsequent-license) ## Sources - [en.wikipedia.org](https://en.wikipedia.org/wiki/Nine_Mile_Point_Nuclear_Generating_Station) — en.wikipedia.org · tier public_source - [nyisoviewer.etariff.biz](https://nyisoviewer.etariff.biz/viewerdoclibrary/Filing/Filing199/199FilingSections/Public%20exctd%20NMP%20LGIA%20FID199%20sprt%20sgs_5419.pdf) — nyisoviewer.etariff.biz · tier public_source - [constellationenergy.com](https://www.constellationenergy.com/about/locations/nine-mile-point-clean-energy-center.html) — constellationenergy.com · tier public_source - [constellationenergy.com](https://www.constellationenergy.com/content/dam/constellationenergy/pdfs/fact-sheets/Nine_Mile_Point_Clean_Energy_Center_Fact_Sheet.pdf) — constellationenergy.com · tier public_source - [federalregister.gov](https://www.federalregister.gov/documents/2001/06/29/01-16387/in-the-matter-of-niagara-mohawk-power-corporation-et-al-nine-mile-point-nuclear-station-unit-nos-1) — federalregister.gov · tier authoritative - [federalregister.gov](https://www.federalregister.gov/documents/2011/11/29/2011-30733/nine-mile-point-nuclear-station-llc-nine-mile-point-nuclear-station-unit-no-2-environmental) — federalregister.gov · tier authoritative - [federalregister.gov](https://www.federalregister.gov/documents/2026/04/29/2026-08276/constellation-energy-generation-llc-nine-mile-point-nuclear-station-unit-1-subsequent-license) — federalregister.gov · tier authoritative - [gevernova.com](https://www.gevernova.com/content/dam/gevernova-nuclear/global/en_us/documents/carbon-free-power/005N9751-BWRX-300-General-Description.pdf) — gevernova.com · tier public_source - [lipower.org](https://www.lipower.org/wp-content/uploads/2019/05/2.2-Approval-Exelon-Generation-for-Nine-Mile-Point-Unit-2.pdf) — lipower.org · tier public_source - [nrc.gov](https://www.nrc.gov/docs/ML2513/ML25135A345.pdf) — nrc.gov · tier authoritative - [nrc.gov](https://www.nrc.gov/reactors/operating/licensing/renewal/applications/nine-mile-pt) — nrc.gov · tier authoritative - [nrc.gov](https://www.nrc.gov/sites/default/files/cdn/doc-collection-news/2026/26-038.pdf) — nrc.gov · tier authoritative - [nucnet.org](https://www.nucnet.org/news/us-constellation-buys-nine-mile-point-for-815-million-dollars) — nucnet.org · tier public_source - [poweronline.com](https://www.poweronline.com/doc/nrc-approves-increased-power-output-for-nine-0001) — poweronline.com · tier public_source ## Data quality - The exact EIA plant is plant ID 2589 and corresponds to the two-unit Nine Mile Point station; NYISO records separately identify Nine Mile Point Units 1 and 2 with distinct PTIDs (23575 and 23744). The official owner page reports approximately 1,907 MW, which matches the anchor capacity_mw of 1,901.1 MW within rounding tolerance. Reported construction costs for Unit 1 ($804.7 million) and Unit 2 ($8.529 billion in 2007 dollars) are historical costs, not construction financing amounts. No retirement of either unit was identified. Unit 1 is currently licensed through August 22, 2029 and has a pending subsequent license renewal application filed March 25, 2026; Unit 2 is licensed through October 31, 2046. Construction and commercial-operation dates are supported by secondary historical sources and official NYISO records; ownership and licensing facts are supported by official owner (Constellation), NRC, and LIPA regulatory sources. The facility's legal and regulatory designation is 'Nine Mile Point Nuclear Station,' while Constellation uses 'Nine Mile Point Clean Energy Center' in public marketing. Unit 2 was subject to a 2012 NRC-approved power uprate of 15% (approximately 521 MW thermal, 158 MW electric); the GE BWR-5 table capacity of 1,277 MW represents pre-uprate capacity. Equipment identification relies on official GE Vernova boiling-water-reactor tables and official NRC licensing documents; no other OEM product pages specific to the installed BWR-2 or BWR-5 models were identified. Ownership history shows four separate utility interests in Unit 2 transferred to Constellation in 2001; LIPA retained its 18% interest throughout. Subsequent parent-company changes (Exelon 2012, Constellation Energy separation 2022) did not affect unit-level asset ownership. Operating responsibility for Unit 2 was held by Constellation until 2014 when it transferred to Exelon Generation; PSEG Long Island manages LIPA's interest. --- Canonical page: https://askthegrid.com/nyiso/assets/plant/nine-mile-point-nuclear-station Source: Ask the Grid — https://askthegrid.com/