Directory of Power Plants in the United States
| Plant Name | Utility | Location | Balancing Authority | Annual Generation | Plant Date | Last Update | Fuel Types |
|---|---|---|---|---|---|---|---|
| OES Biogas Power | Organic Energy Solutions, Inc. | San Bernardino, CA | California Independent System Operator (CISO) | 4.9 GWh | - | Dec 2024 | Other Biomass Gas |
| Orange Grove | Orange Grove | Jim Wells, TX | Electric Reliability Council of Texas, Inc. (ERCO) | 112.9 GWh | - | Sep 2025 | Solar |
| Oriana Solar LLC | Oriana Solar LLC | Victoria, TX | Electric Reliability Council of Texas, Inc. (ERCO) | 38.2 GWh | - | Sep 2025 | Solar |
| Ocoee 1 | Tennessee Valley Authority | Benton, TN | Tennessee Valley Authority (TVA) | 69.2 GWh | Dec 1911 | Dec 2024 | Water |
| Ocoee 2 | Tennessee Valley Authority | Benton, TN | Tennessee Valley Authority (TVA) | 86.7 GWh | Sep 1913 | Dec 2024 | Water |
| Oswego Falls East | Erie Boulevard Hydropower LP | Fulton, NY | New York Independent System Operator (NYIS) | 23.1 GWh | Dec 1913 | Dec 2024 | Water |
| Oswego Falls West | Erie Boulevard Hydropower LP | Fulton, NY | New York Independent System Operator (NYIS) | 8.1 GWh | Dec 1913 | Dec 2024 | Water |
| Oneida | PacifiCorp | Riverdale, ID | PacifiCorp East (PACE) | 42.0 GWh | Jun 1915 | Dec 2024 | Water |
| Oconto Falls Upper | Eagle Creek Renewable Energy, LLC | Oconto Falls, WI | Midcontinent Independent System Operator, Inc. (MISO) | 6.5 GWh | Dec 1917 | Dec 2024 | Water |
| Oak Grove | Portland General Electric Co | Estacada, OR | Portland General Electric Company (PGE) | 150.1 GWh | Jul 1924 | Dec 2024 | Water |
| Oakdale | Northern Indiana Pub Serv Co | Monticello, IN | Midcontinent Independent System Operator, Inc. (MISO) | 17.4 GWh | Oct 1925 | Dec 2024 | Water |
| Ohio Falls | Louisville Gas & Electric Co | Shippingport Island, KY | Louisville Gas and Electric Company and Kentucky Utilities Company (LGEE) | 235.5 GWh | Dec 1927 | Dec 2024 | Water |
| Oxford Dam | Duke Energy Carolinas, LLC | Conover, NC | Duke Energy Carolinas (DUK) | 91.9 GWh | Mar 1928 | Dec 2024 | Water |
| Ozark Beach | Empire District Electric Co | Forsyth, MO | Southwest Power Pool (SWPP) | 53.2 GWh | May 1931 | Dec 2024 | Water |
| Ottumwa City of | Ottumwa City of | Ottumwa, IA | Midcontinent Independent System Operator, Inc. (MISO) | 4.5 GWh | Jul 1931 | Apr 2024 | Water |
| Osage Dam | Union Electric Co - (MO) | Eldon, MO | Midcontinent Independent System Operator, Inc. (MISO) | 497.1 GWh | Sep 1931 | Dec 2024 | Water |
| Ocoee 3 | Tennessee Valley Authority | Benton, TN | Tennessee Valley Authority (TVA) | 151.7 GWh | Mar 1943 | Dec 2024 | Water |
| Oberlin (OH) | City of Oberlin - (OH) | Oberlin, OH | PJM Interconnection, LLC (PJM) | 634.0 MWh | Dec 1947 | Dec 2024 | Natural Gas : 87.7% Distillate Fuel Oil : 12.3% |
| O H Hutchings | Kimura Power LLC | Miamisburg, OH | PJM Interconnection, LLC (PJM) | 397.0 MWh | Jun 1948 | Dec 2024 | Natural Gas |
| Orrville | City of Orrville - (OH) | Orrville, OH | PJM Interconnection, LLC (PJM) | 22.0 GWh | Dec 1948 | Aug 2024 | Bituminous Coal : 51.7% Natural Gas : 48.3% |
| Osawatomie City of | City of Osawatomie - (KS) | Osawatomie, KS | Southwest Power Pool (SWPP) | 10.0 MWh | Sep 1950 | Dec 2023 | Distillate Fuel Oil |
| Oakdale Power Station | Massachusetts Water Res Auth | West Boylston, MA | ISO New England (ISNE) | 13.9 GWh | Apr 1951 | Dec 2024 | Water |
| Ogden | City of Ogden - (IA) | Ogden, IA | Midcontinent Independent System Operator, Inc. (MISO) | 10.0 MWh | Jun 1951 | Dec 2024 | Distillate Fuel Oil |
| Oxford (NE) | Village of Oxford - (NE) | Oxford, NE | Southwest Power Pool (SWPP) | 27.0 MWh | Jul 1953 | Dec 2024 | Natural Gas : 89.8% Distillate Fuel Oil : 10.2% |
| Oberlin (KS) | City of Oberlin - (KS) | Oberlin, KS | Southwest Power Pool (SWPP) | 11.8 MWh | Dec 1953 | Dec 2024 | Distillate Fuel Oil |
| Old Hickory | USCE-Nashville District | Hendersonville, TN | Tennessee Valley Authority (TVA) | 436.6 GWh | Mar 1957 | Dec 2024 | Water |
| Osborne | City of Osborne - (KS) | Osborne, KS | Southwest Power Pool (SWPP) | 15.7 MWh | May 1957 | Dec 2024 | Distillate Fuel Oil : 80.6% Natural Gas : 19.4% |
| Ottawa | City of Ottawa - (KS) | Ottawa, KS | Southwest Power Pool (SWPP) | 689.0 MWh | Nov 1958 | Dec 2024 | Natural Gas : 74.5% Distillate Fuel Oil : 25.5% |
| Oliver Dam | Georgia Power Co | Columbus, GA | Southern Company Services, Inc. - Trans (SOCO) | 128.4 GWh | Jun 1959 | Dec 2024 | Water |
| Ocotillo | Arizona Public Service Co | Tempe, AZ | Arizona Public Service Company (AZPS) | 473.2 GWh | Feb 1960 | Sep 2025 | Natural Gas |
| Oxbow (OR) | Idaho Power Co | Oxbow, OR | Idaho Power Company (IPCO) | 965.3 GWh | Jun 1961 | Dec 2024 | Water |
| Oahe | USACE-Omaha | Pierre, SD | Southwest Power Pool (SWPP) | 2.2 TWh | Mar 1962 | Dec 2024 | Water |
| Ord | City of Ord - (NE) | Ord, NE | Southwest Power Pool (SWPP) | 106.0 MWh | Dec 1962 | Dec 2024 | Distillate Fuel Oil |
| Osage (IA) | City of Osage - (IA) | Osage, IA | Midcontinent Independent System Operator, Inc. (MISO) | 5.6 GWh | Aug 1963 | Dec 2024 | Wind : 81.2% Solar : 18.8% |
| Oxbow (CA) | Placer County Water Agency | Foresthill, CA | California Independent System Operator (CISO) | 29.2 GWh | Sep 1966 | Sep 2024 | Water |
| Oak Bluffs Diesel Generating Facility | Vineyard Reliability LLC | Oak Bluffs, MA | ISO New England (ISNE) | 2.1 GWh | Dec 1968 | Dec 2024 | Distillate Fuel Oil |
| Oconto Falls Lower | Eagle Creek Renewable Energy, LLC | Oconto Falls, WI | Midcontinent Independent System Operator, Inc. (MISO) | 6.9 GWh | Dec 1970 | Dec 2024 | Water |
| Ormond Beach | Ormond Beach Power, LLC | Oxnard, CA | California Independent System Operator (CISO) | 43.1 GWh | Jul 1971 | Aug 2025 | Natural Gas |
| O W Sommers | City of San Antonio - (TX) | San Antonio, TX | Electric Reliability Council of Texas, Inc. (ERCO) | 2.5 TWh | Mar 1972 | Dec 2024 | Natural Gas |
| Ozark | USCE-Little Rock District | Ozark, AR | Southwestern Power Administration (SPA) | 314.7 GWh | Oct 1972 | Dec 2024 | Water |
| Oconee | Duke Energy Carolinas, LLC | Seneca, SC | Duke Energy Carolinas (DUK) | 22.6 TWh | Jun 1973 | Sep 2025 | Nuclear |
| Oswego Harbor Power | Oswego Harbor Power | Oswego, NY | New York Independent System Operator (NYIS) | 91.0 GWh | May 1975 | Aug 2025 | Residual Fuel Oil : 99.5% |
| Old Faithful | NorthWestern Energy (MT wind/thermal) | Yellowstone, WY | NorthWestern Corporation (NWMT) | 273.0 MWh | Nov 1979 | Dec 2024 | Distillate Fuel Oil |
| Ottumwa | Interstate Power and Light Co | Ottumwa, IA | Midcontinent Independent System Operator, Inc. (MISO) | 2.9 TWh | Apr 1981 | Sep 2025 | Subbituminous Coal : 99.7% |
| Oxnard Wastewater Treatment Plant | Oxnard City of | Oxnard, CA | California Independent System Operator (CISO) | 4.2 GWh | Jul 1981 | Sep 2025 | Other Biomass Gas : 95.1% Natural Gas : 4.9% |
| Owatonna | City of Owatonna - (MN) | Owatonna, MN | Midcontinent Independent System Operator, Inc. (MISO) | 1.4 GWh | Mar 1982 | Dec 2023 | Natural Gas |
| Oak Creek Energy Systems I | Terra-Gen Operating Co-Wind | Mojave, CA | California Independent System Operator (CISO) | 54.5 GWh | May 1982 | Dec 2024 | Wind |
| Oxnard | Procter&Gamble Paper Products Co-Oxnard | Oxnard, CA | California Independent System Operator (CISO) | 479.4 GWh | Jun 1982 | Sep 2025 | Natural Gas |
| Ottauquechee Hydro | Green Mountain Power Corp | N. Hartland, VT | ISO New England (ISNE) | 978.0 MWh | Mar 1983 | Dec 2024 | Water |
| Orca | Cordova Electric Coop, Inc | Cordova, AK | 4.2 GWh | Sep 1984 | Dec 2024 | Distillate Fuel Oil | |
| Opal Springs Hydro | Deschutes Valley Water District | Culver, OR | PacifiCorp West (PACW) | 29.4 GWh | Dec 1984 | Dec 2024 | Water |
| Otis Hydro | Eagle Creek Renewable Energy, LLC | Livermore Falls, ME | ISO New England (ISNE) | 27.7 GWh | Dec 1984 | Sep 2025 | Water |
| Owyhee Dam Power Project | Owyhee Irrigation District | Nyssa, OR | Idaho Power Company (IPCO) | 27.6 GWh | Jul 1985 | Oct 2024 | Water |
| Odyssey Energy Altura Cogen, LLC | Odyssey Operating Services | Channelview, TX | Electric Reliability Council of Texas, Inc. (ERCO) | 3.7 TWh | Oct 1985 | Sep 2025 | Natural Gas |
| Omega Hills Gas Recovery | WM Renewable Energy LLC | Germantown, WI | Midcontinent Independent System Operator, Inc. (MISO) | 80.1 GWh | Nov 1985 | Sep 2025 | Landfill Gas |
| Oswego County Energy Recovery | Oswego County | Fulton, NY | New York Independent System Operator (NYIS) | 8.1 GWh | Jan 1986 | Dec 2024 | Non-biogenic Municipal Solid Waste : 55.0% Biogenic Municipal Solid Waste : 45.0% |
| Oxnard Paper Mill | New-Indy, Oxnard LLC | Oxnard, CA | California Independent System Operator (CISO) | 133.9 GWh | Feb 1986 | Sep 2025 | Natural Gas |
| Ormesa I | Ormat Nevada Inc | Holtville, CA | Imperial Irrigation District (IID) | 70.2 GWh | Nov 1986 | Dec 2024 | Geothermal |
| Olive View Medical Center | Los Angeles County DHS | Sylmar, CA | Los Angeles Department of Water and Power (LDWP) | 11.4 GWh | Jan 1987 | Feb 2024 | Natural Gas |
| Orchard Avenue 1 | Yakima-Tieton Irrigation Dist | Yakima, WA | PacifiCorp West (PACW) | 2.5 GWh | Feb 1987 | Sep 2024 | Water |
| Olmsted Waste Energy | Olmsted County Public Works | Rochester, MN | Midcontinent Independent System Operator, Inc. (MISO) | 46.7 GWh | Mar 1987 | Dec 2024 | Non-biogenic Municipal Solid Waste : 54.7% Biogenic Municipal Solid Waste : 44.7% Natural Gas : 0.5% |
| Ogdensburg | Ampersand Ogdensburg Hydro, LLC | Ogdensburg, NY | New York Independent System Operator (NYIS) | 4.0 GWh | Nov 1987 | Dec 2023 | Water |
| Ormesa II | Ormat Nevada Inc | Holtville, CA | Imperial Irrigation District (IID) | 131.7 GWh | Apr 1989 | Dec 2024 | Geothermal |
| Ormesa III | Ormat Nevada Inc | Holtville, CA | Imperial Irrigation District (IID) | 44.4 GWh | Apr 1989 | Dec 2024 | Geothermal |
| Olsen | Olsen Power Partners | Whitmore, CA | California Independent System Operator (CISO) | 13.5 GWh | Dec 1989 | Dec 2024 | Water |
| Oroville Cogeneration LP | Apex Power Generation Corp. | Oroville, CA | California Independent System Operator (CISO) | 672.3 MWh | Dec 1989 | Dec 2024 | Natural Gas |
| Ocean State Power | Ocean State Power Co | Harrisville, RI | ISO New England (ISNE) | 1.2 TWh | Nov 1990 | Dec 2024 | Natural Gas : 99.9% |
| Ocean State Power II | Ocean State Power II | Harrisville, RI | ISO New England (ISNE) | 896.8 GWh | Sep 1991 | Dec 2024 | Natural Gas : 99.9% |
| Orlando Cogen LP | Florida Municipal Power Agency | Orlando, FL | Duke Energy Florida, Inc. (FPC) | 704.8 GWh | Aug 1993 | Dec 2024 | Natural Gas |
| Oyster Creek Unit VIII | Dow Chemical Company-Oyster Creek VIII | Freeport, TX | Electric Reliability Council of Texas, Inc. (ERCO) | 2.3 TWh | Sep 1994 | Sep 2025 | Natural Gas : 99.8% |
| Onondaga County Resource Recovery | Covanta Onondega LP | Jamesville, NY | New York Independent System Operator (NYIS) | 206.3 GWh | Oct 1994 | Sep 2025 | Non-biogenic Municipal Solid Waste : 54.5% Biogenic Municipal Solid Waste : 44.6% Natural Gas : 0.9% |
| Orange Cogeneration Facility | Northern Star Generation Services Co LLC | Bartow, FL | Duke Energy Florida, Inc. (FPC) | 387.5 GWh | Jan 1995 | Dec 2024 | Natural Gas |
| Opryland USA | Gaylord Entertainment Co | Nashville, TN | Tennessee Valley Authority (TVA) | 6.6 GWh | Jun 1995 | Sep 2025 | Natural Gas |
| Otsego Mill Power Plant | Otsego Paper Inc | Otsego, MI | Midcontinent Independent System Operator, Inc. (MISO) | 165.5 GWh | Oct 1995 | Dec 2024 | Natural Gas |
| Okeelanta Cogeneration | New Hope Power Company | South Bay, FL | Florida Power & Light Co. (FPL) | 51.4 GWh | Dec 1995 | Sep 2025 | Agricultural By-Products : 97.8% Natural Gas : 2.2% |
| Ocean County Landfill | NextEra Renewable Fuels, LLC | Manchester, NJ | PJM Interconnection, LLC (PJM) | 64.3 GWh | Jan 1997 | Dec 2024 | Landfill Gas |
| Orrville Peaking | American Mun Power-Ohio, Inc | Orrville, OH | PJM Interconnection, LLC (PJM) | 209.0 MWh | Jun 1999 | Dec 2024 | Distillate Fuel Oil |
| Oxford (KS) | City of Oxford - (KS) | Oxford, KS | Southwest Power Pool (SWPP) | 10.0 MWh | Jun 1999 | Dec 2024 | Distillate Fuel Oil |
| Oak Point Cogen | Chevron Oronite Co LLC | Belle Chasse, LA | Midcontinent Independent System Operator, Inc. (MISO) | 99.2 GWh | Sep 1999 | Dec 2024 | Natural Gas |
| Odessa-Ector Power Plant | LaFrontera Holdings LLC | Odessa, TX | Electric Reliability Council of Texas, Inc. (ERCO) | 7.9 TWh | Jun 2001 | Sep 2025 | Natural Gas |
| Old Gold Energy Center, LLC | Old Gold Energy Center, LLC | Joice, IA | Midcontinent Independent System Operator, Inc. (MISO) | 78.4 GWh | Sep 2001 | Dec 2024 | Wind |
| Osceola Generating Station (FL) | Orlando Utilities Comm | St. Cloud, FL | Duke Energy Florida, Inc. (FPC) | 623.0 MWh | Nov 2001 | Dec 2024 | Natural Gas : 87.4% Distillate Fuel Oil : 12.6% |
| Ontelaunee Energy Center | Ontelaunee Energy Center | Reading, PA | PJM Interconnection, LLC (PJM) | 4.1 TWh | Apr 2002 | Sep 2025 | Natural Gas |
| Oleander Power Project LP | Oleander Holdings LLC | Cocoa, FL | Florida Power & Light Co. (FPL) | 488.9 GWh | May 2002 | Dec 2024 | Natural Gas : 99.9% |
| Oneta Energy Center | Oneta Power LLC | Broken Arrow, OK | Southwest Power Pool (SWPP) | 5.1 TWh | Jun 2002 | Sep 2025 | Natural Gas |
| Oswegatchie | Erie Boulevard Hydropower LP | Edwards, NY | New York Independent System Operator (NYIS) | 8.5 GWh | Jul 2002 | Dec 2024 | Water |
| Ouachita | Entergy Louisiana LLC | Sterlington, LA | Midcontinent Independent System Operator, Inc. (MISO) | 4.3 TWh | Jul 2002 | Sep 2025 | Natural Gas |
| Onancock Diesel Generation Facility | Old Dominion Electric Coop | Onancock, VA | PJM Interconnection, LLC (PJM) | 264.0 MWh | Oct 2002 | Dec 2024 | Distillate Fuel Oil |
| Overall Road Station | City of Farmington - (MO) | Farmington, MO | Midcontinent Independent System Operator, Inc. (MISO) | 26.0 MWh | Feb 2003 | Dec 2024 | Distillate Fuel Oil |
| Osawatomie | Evergy Metro | Miami, KS | Southwest Power Pool (SWPP) | 58.8 GWh | May 2003 | Dec 2024 | Natural Gas |
| Oklahoma Wind Energy Center | FPL Energy Oklahoma Wind LLC | Woodward, OK | Southwest Power Pool (SWPP) | 145.4 GWh | Sep 2003 | Dec 2024 | Wind |
| Ontario LFGTE | Seneca Energy II | Stanley, NY | New York Independent System Operator (NYIS) | 68.5 GWh | Oct 2003 | Dec 2024 | Landfill Gas |
| Oak Ridge LFGTE | Wabash Valley Power Assn, Inc | Logansport, IN | Midcontinent Independent System Operator, Inc. (MISO) | 25.8 GWh | Nov 2003 | Dec 2024 | Landfill Gas |
| One Market Plaza | Paramount Group Inc | San Francisco, CA | California Independent System Operator (CISO) | 177.0 MWh | Nov 2003 | Dec 2024 | Natural Gas |
| Orchard Park | Borough of Chambersburg | Chambersburg, PA | PJM Interconnection, LLC (PJM) | 41.0 GWh | Nov 2003 | Sep 2025 | Natural Gas : 94.9% Distillate Fuel Oil : 5.1% |
| Otter Creek Ethanol Poet - Ashton | Otter Creek Ethanol LLC - Poet Ashton | Ashton, IA | Midcontinent Independent System Operator, Inc. (MISO) | 43.5 GWh | Feb 2004 | Sep 2025 | Natural Gas |
| Osprey Energy Center Power Plant | Duke Energy Florida, LLC | Auburndale, FL | Tampa Electric Company (TEC) | 3.8 TWh | Apr 2004 | Sep 2025 | Natural Gas |
| Oasis Wind | Terra-Gen Operating Co-Wind | Mojave, CA | California Independent System Operator (CISO) | 238.4 GWh | Nov 2004 | Dec 2024 | Wind |
| Orange Street G1 | Town of Bedford - (VA) | Bedford, VA | PJM Interconnection, LLC (PJM) | 168.0 MWh | Jun 2005 | Dec 2024 | Distillate Fuel Oil |
| OREG 1 Inc | Ormat Nevada Inc | Culbertson, MT | Southwest Power Pool (SWPP) | 143.8 GWh | Jun 2006 | Sep 2025 | Waste Heat |
Summary of Power Plants By State
Figures are based on September 2025 generation numbers.| State | Rank | Active Plants | Sep 2025 Generation |
|---|---|---|---|
| Alabama | # 7 | 76 | 12,052.47 GWh |
| Alaska | # 48 | 147 | 527.57 GWh |
| Arizona | # 9 | 183 | 11,602.92 GWh |
| Arkansas | # 21 | 117 | 5,844.09 GWh |
| California | # 4 | 1,769 | 19,371.91 GWh |
| Colorado | # 30 | 304 | 4,433.17 GWh |
| Connecticut | # 32 | 168 | 3,779.74 GWh |
| Delaware | # 49 | 33 | 419.31 GWh |
| District of Columbia | # 51 | 16 | 16.99 GWh |
| Florida | # 2 | 323 | 24,446.09 GWh |
| Georgia | # 8 | 266 | 11,628.97 GWh |
| Hawaii | # 47 | 73 | 826.54 GWh |
| Idaho | # 44 | 148 | 1,495.33 GWh |
| Illinois | # 5 | 385 | 14,642.93 GWh |
| Indiana | # 14 | 213 | 8,730.35 GWh |
| Iowa | # 26 | 295 | 5,224.35 GWh |
| Kansas | # 25 | 189 | 5,250.86 GWh |
| Kentucky | # 23 | 60 | 5,806.86 GWh |
| Louisiana | # 13 | 87 | 9,343.34 GWh |
| Maine | # 45 | 217 | 1,135.36 GWh |
| Maryland | # 39 | 204 | 2,935.42 GWh |
| Massachusetts | # 41 | 652 | 1,746.92 GWh |
| Michigan | # 11 | 279 | 10,468.02 GWh |
| Minnesota | # 29 | 769 | 4,717.95 GWh |
| Mississippi | # 20 | 58 | 6,625.37 GWh |
| Missouri | # 22 | 128 | 5,843.17 GWh |
| State | Rank | Active Plants | Sep 2025 Generation |
|---|---|---|---|
| Montana | # 40 | 72 | 1,949.24 GWh |
| Nebraska | # 34 | 132 | 3,501.38 GWh |
| Nevada | # 31 | 114 | 4,053.88 GWh |
| New Hampshire | # 42 | 60 | 1,549.07 GWh |
| New Jersey | # 27 | 399 | 4,969.45 GWh |
| New Mexico | # 36 | 145 | 3,317.84 GWh |
| New York | # 12 | 966 | 10,145.62 GWh |
| North Carolina | # 10 | 917 | 11,211.15 GWh |
| North Dakota | # 37 | 60 | 3,089.17 GWh |
| Ohio | # 6 | 201 | 12,818.31 GWh |
| Oklahoma | # 17 | 143 | 7,364.05 GWh |
| Oregon | # 28 | 282 | 4,812.51 GWh |
| Pennsylvania | # 3 | 260 | 19,731.43 GWh |
| Rhode Island | # 46 | 100 | 863.62 GWh |
| South Carolina | # 16 | 207 | 7,861.23 GWh |
| South Dakota | # 43 | 52 | 1,535.17 GWh |
| Tennessee | # 19 | 88 | 6,829.06 GWh |
| Texas | # 1 | 946 | 51,969.48 GWh |
| Utah | # 35 | 126 | 3,419.48 GWh |
| Vermont | # 50 | 120 | 165.14 GWh |
| Virginia | # 15 | 241 | 8,580.52 GWh |
| Washington | # 18 | 138 | 7,120.43 GWh |
| West Virginia | # 38 | 39 | 3,057.29 GWh |
| Wisconsin | # 24 | 251 | 5,674.74 GWh |
| Wyoming | # 33 | 73 | 3,641.70 GWh |