Naughton Power Plant
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Naughton Power Plant is an operating power station of at least 384-megawatts (MW) in Kemmerer, Lincoln, Wyoming, United States with multiple units, some of which are not currently operating.
Location
Table 1: Project-level location details
| Plant name | Location | Coordinates (WGS 84) |
|---|---|---|
| Naughton Power Plant | Kemmerer, Lincoln, Wyoming, United States | 41.758886, -110.597031 (exact) |
Unit-level coordinates (WGS 84):
- Unit 1, Unit 2, Unit 3: 41.758886, -110.597031
Project Details
Table 2: Unit-level details
| Unit name | Status | Fuel(s) | Capacity (MW) | Technology | CHP | Start year | Retired year | Emergency/Backup |
|---|---|---|---|---|---|---|---|---|
| Unit 1, timepoint 1 | Retired[1] | coal: subbituminous[2] | 192 | subcritical | – | 1963 | 2025[1] | no |
| Unit 1, timepoint 2 | Pre-construction[3][4][5] | fossil gas: natural gas[5] | 192[6] | steam turbine[7] | – | 2026 (planned)[3][5] | 2036 (planned)[5] | no |
| Unit 2, timepoint 1 | Retired[1] | coal: subbituminous[2] | 256 | subcritical | – | 1968 | 2025[1] | no |
| Unit 2, timepoint 2 | Pre-construction[5][3][4] | fossil gas: natural gas[5] | 256[6] | steam turbine[7] | – | 2026 (planned)[3][5] | 2036 (planned)[5] | no |
| Unit 3, timepoint 1 | Retired | coal: subbituminous[2] | 384 | subcritical | no[8] | 1971 | 2019 | no |
| Unit 3, timepoint 2 | Operating[8] | fossil gas: natural gas[8] | 384[8] | steam turbine[8] | no[8] | 2021[8][9] | 2029 (planned)[10] | no |
CHP is an abbreviation for Combined Heat and Power. It is a technology that produces electricity and thermal energy at high efficiencies. Coal units track this information in the Captive Use section when known.
Table 3: Unit-level ownership and operator details
| Unit name | Owner | Parent |
|---|---|---|
| Unit 1, timepoint 1 | PacifiCorp [100%] | Berkshire Hathaway Inc [100.0%] |
| Unit 1, timepoint 2 | PacifiCorp [100%] | Berkshire Hathaway Inc [100.0%] |
| Unit 2, timepoint 1 | PacifiCorp [100%] | Berkshire Hathaway Inc [100.0%] |
| Unit 2, timepoint 2 | PacifiCorp [100%] | Berkshire Hathaway Inc [100.0%] |
| Unit 3, timepoint 1 | PacifiCorp [100%] | Berkshire Hathaway Inc [100.0%] |
| Unit 3, timepoint 2 | PacifiCorp [100%] | Berkshire Hathaway Inc [100.0%] |
Unit-level fuel conversion details:
Unit 1: Conversion in pre-construction phase from coal to fossil gas in 2026.
Unit 2: Conversion in pre-construction phase from coal to fossil gas in 2026.
Unit 3: Converted from coal to fossil gas in 2021.
Project-level coal details
- Coal source(s): domestic
Impacts
Potential emissions and details on the project's status and permit applications can be viewed on Oil and Gas Watch page here.
The Oil and Gas Watch database, created by Environmental Integrity Project (EIP), is a free, public-facing tool designed to track the rapid expansion of fossil fuel and petrochemical infrastructure in the United States. Oil and Gas Watch maps new and expanding oil, gas, and petrochemical infrastructure projects across the country and monitors each project’s construction status so the public can stay informed about major oil and gas developments being proposed in their communities. We track key environmental approvals companies must obtain before starting construction or operations and provide access to thousands of government records and permits unearthed by our analysts.
Ownership Tree
This ownership tree is part of the Global Energy Ownership Tracker, a project of Global Energy Monitor.
Retirements
In 2014 PacifiCorp said unit 3 will be closed by 2017, and will switch on six months later as a natural gas-burning unit.[11][12]
In June 2015, PacifiCorp said Units 1 & 2 are scheduled for retirement by 2029.[13]
In 2018 it was unclear if unit 3 will be converted to natural gas or closed indefinitely.[14]
The Company was required to cease coal-fired operations in Naughton Unit 3 on January 30, 2019, to maintain compliance with certain environmental regulations,[15] and a gas conversion was being contemplated at the site.[16]
An April 2019 study by PacifiCorp identified both units 1 & 2 as being less economic to operate beyond 2022 than alternatives. Both were candidates for early retirement.[17]
In September 2019, it was reported the entire power station was planned to close by 2025.[18][19]
PacifiCorp's 2021 Integrated Resource Plan (IRP) also showed units 1 and 2 retiring in 2025.[20]
In their 2023 IRP, PacifiCorp now said that Naughton coal units 1 and 2 would be converted to gas in 2026, and that the gas units would operate through 2036.[21]
According to PacifiCorp’s 2025 IRP and reporting from April 2025, the utility still planned to convert coal Units 1 and 2 to gas by 2026.[22][23]
In March 2026, PacifiCorp’s 2025 IRP Update stated that Naughton’s coal Units 1 and 2 stopped burning coal on December 31, 2025.[24]
Nuclear proposal
In November 2021, TerraPower announced it had selected Kemmerer, Wyoming, near PacifiCorp's retiring coal-fired Naughton Power Plant, as the site of its Natrium nuclear reactor demonstration project. The company anticipated submitting the demonstration plant's construction permit application to the U.S. Nuclear Regulatory Commission in mid-2023, and planned to have the advanced reactor operational in 2028. The 2021 IRP showed the 500-MW Natrium demonstration project coming on line by summer 2028.[20]
Coal Supply
The Kemmerer mine that supplies the coal to the Naugton Power plant was formerly owned by Westmoreland Coal. After if bankruptcy in 2019 it handed over the coal mine to its lenders becasue it could not find a buyer. The lenders will continue to operate the mine. [25] The Naughton plant is the sole buyer for Kemmerer mine's coal, if PacifiCorp decided to close the entire plant early the mine could also be closed in the process.
Emissions Data
- 2024 Gross Load (MWh): 1,844,046[26]
- 2024 SO2 Mass (short tons): 1,021[26]
- 2024 CO2 Mass (short tons): 2,075,974[26]
- 2024 NOx Mass (short tons): 2,021[26]
- 2023 Mercury emissions (Hg, lb): 13.41[27][28]
Coal ash at Naughton
According to a 2007 risk assessment report released by the EPA, Wyoming had 17 coal ponds at 5 coal-fired power plant sites. Of these ponds, 11 were over 30 years in age and 4 were over 40 years old. Additionally, four surface impoundments and landfills were reported as being unlined, and two that were clay-lined.
The history of coal ash releases in Wyoming were as follows:
- 55,000 cubic yards of fly ash spilled from a pond at the Naughton Power Plant
- In January 2009, 14,400 gallons of coal ash processing water overflowed the canal at a coal ash pond at the Dave Johnston Power Plant
- Seepage occurred at the Bridger Power Station, where 10,000 gallons of coal ash was released per month, which was then pumped back into the pond[29]
In November 2025, the Environmental Protection Agency (EPA) proposed to delay the closure deadline for unlined coal ash ponds at eleven coal plants, including Naughton Power Plant. Under a 2015 rule, unlined coal ash ponds were to cease receiving waste by April 2021, but in 2020, the then Trump administration extended the deadline to October 2028. The EPA’s latest proposal would allow the eleven coal plants to continue operating and dumping coal ash into unlined ponds until October 2031.[30][31] Earthjustice said that all of the unlined coal ash ponds at the eleven plants were known to be contaminating surrounding groundwater, and that courts had already ruled that the plants cannot dump coal ash into holding ponds that leak pollutants into the groundwater.[30]
Naughton ranked 58th on list of most polluting power plants in terms of coal waste
In January 2009, Sue Sturgis of the Institute of Southern Studies compiled a list of the 100 most polluting coal plants in the United States in terms of coal combustion waste (CCW) stored in surface impoundments like the one involved in the TVA Kingston Fossil Plant coal ash spill.[32] The data came from the EPA's Toxics Release Inventory (TRI) for 2006, the most recent year available.[33]
Naughton Power Plant ranked number 58 on the list, with 517,966 pounds of coal combustion waste released to surface impoundments in 2006.[32]
Citizen groups
- Powder River Basin Resource Council
- Sierra Club Wyoming Chapter
- Wyoming Conservation Voters
- Wyoming Conservation Voters Education Fund
- Wyoming Outdoor Council
Articles and Resources
References
- ↑ 1.0 1.1 1.2 1.3 "2025 Integrated Resource Plan Update" (PDF). PacifiCorp. 2026-03-31. Archived from the original (PDF) on 2026-07-07. Retrieved 2026-07-07.
- ↑ 2.0 2.1 2.2 https://www.gem.wiki/Coal_source_methodology_for_the_Global_Coal_Plant_Tracker.
{{cite web}}: Missing or empty|title=(help) - ↑ 3.0 3.1 3.2 3.3 "Kemmerer power plant's coal-to-natural-gas conversion highlights uncertainty for Wyoming communities". WyoFile. 2025-12-15. Archived from the original on 2026-01-21. Retrieved 2025-12-15.
- ↑ 4.0 4.1 https://wyofile.com/pacificorp-throws-lifeline-to-one-wyoming-power-plant-confirms-end-of-coal-at-another/.
{{cite web}}: Missing or empty|title=(help) - ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 "2023 Integrated Resource Plan" (PDF). PacifiCorp. 2023-03-31. Archived from the original (PDF) on 2024-03-20.
- ↑ 6.0 6.1 "10th Circuit Rejects EPA Wyoming Haze Reduction Rule". The Quad Report. 2023-09-01. Archived from the original on 2025-03-07. Retrieved 2024-11-08.
- ↑ 7.0 7.1 https://www.eia.gov/electricity/data/eia860m/xls/september_generator2024.xlsx.
{{cite web}}: Missing or empty|title=(help) - ↑ 8.0 8.1 8.2 8.3 8.4 8.5 8.6 "U.S. Energy Information Administration, Preliminary Monthly Electric Generator Inventory (July 2021)". Archived from the original on 2021-11-22. Retrieved October 13, 2021.
- ↑ https://web.archive.org/web/20220709061700/https://www.transmissionhub.com/articles/2016/12/pacificorp-pushing-back-date-to-end-coal-use-at-naughton-unit-3-in-wyoming.html. Archived from the original on 2022-07-09.
{{cite web}}: Missing or empty|title=(help) - ↑ "U.S. Energy Information Administration, Preliminary Monthly Electric Generator Inventory (April 2022)". Archived from the original on 2022-07-12. Retrieved June 10, 2022.
- ↑ "The big switch: utilities' conversion from coal to natural gas," Casper Star-Tribune, May 31, 2014
- ↑ "PacifiCorp Long Range Energy Plan Calls for Less Coal, More Energy Efficiency," PacifiCorp, June 8, 2015
- ↑ "PacifiCorp Long Range Energy Plan Calls for Less Coal, More Energy Efficiency," PacifiCorp, June 8, 2015
- ↑ "Tied to coal, Kemmerer’s future looks uncertain," WyoFile, May 8, 2018
- ↑ "Victim of times, Kemmerer coal-fired generator shuts down," Wyoming News Exchange, Jan 31, 2019
- ↑ "Direct Testimony of Robert Van Engelenhoven," Rocky Mountain Power PSC Filing, May 2020
- ↑ "PacifiCorp updates economic analysis of coal fleet," PacifiCorp, April 25, 2019
- ↑ "Pacifcorp sees 2 GW coal retirements, $599M savings by 2040 in latest planning scenarios," Utility Dive, Sept. 11, 2019
- ↑ "PacifiCorp to add 7 GW renewables + storage, close 20 of 24 coal plants," Utility Dive, Oct 3, 2019
- ↑ 20.0 20.1 "TerraPower Selects PacifiCorp's Retiring Naughton Plant as Site for Demo Reactor," California Energy Markets, November 19, 2021
- ↑ “2023 Integrated Resource Plan - Volume I,” PacifiCorp, March 31, 2023
- ↑ “2025 Integrated Resource Plan - Volume I - March 31, 2025,” PacifiCorp, March 31, 2025
- ↑ “PacifiCorp throws lifeline to one Wyoming power plant, confirms end of coal at another,” Wyofile, April 4, 2025
- ↑ “2025 Integrated Resource Plan Update,” PacifiCorp, March 31, 2026
- ↑ https://www.wyomingpublicmedia.org/post/westmoreland-secured-lenders-take-over-kemmerer-mine#stream/
- ↑ 26.0 26.1 26.2 26.3 EIA (2024). "Clean Air Markets Program Data (CAMD)". Retrieved 2025-02-20.
- ↑ Clean Air and Power Division, U.S. Environmental Protection Agency (February 2024). "Annual data 2022 vs. 2023". Retrieved 2025-03-04.
- ↑ Toxics Release Inventory, U.S. Environmental Protection Agency (October 2024). "2023 Basic Plus Data". Retrieved 2025-03-04.
- ↑ "Wyoming Coal Ash Factsheet" Earthjustice, accessed November 16. 2011.
- ↑ 30.0 30.1 “EPA Proposes to Delay Closure of Some of the Largest Toxic Coal Ash Ponds, in Violation of the Law,” Earthjustice, November 25, 2025
- ↑ “Trump administration proposes to extend the life of some coal plants,” The Hill, November 26, 2025
- ↑ 32.0 32.1 Sue Sturgis, "Coal's ticking timebomb: Could disaster strike a coal ash dump near you?," Institute for Southern Studies, January 4, 2009.
- ↑ TRI Explorer, EPA, accessed January 2009.
Additional data
To access additional data, including interactive maps of the power stations, downloadable datasets, and summary data, please visit the Global Coal Plant Tracker and the Global Oil and Gas Plant Tracker on the Global Energy Monitor website.
