Muddy Run
Muddy Run is a pumped-storage hydro plant in Lancaster County, Pennsylvania, operated by Constellation Power, Inc. Among the 33 pumped-storage plants in the country it is the seventh-largest. Counting by its oldest working unit (1967), it is the eighth-oldest of the 33 pumped-storage plants still running in the United States.
Nameplate capacity, 2025
1,072 MW
1,058 MW net summer capacity
8 operable units
- Pumped-storage hydro1,072 MW100%
Unit by unit, 1967 to 2025
operating in 2025bar height follows unit size
Unit 1 Pumped-storage hydro, 134 MW, 1967
Unit 2 Pumped-storage hydro, 134 MW, 1967
Unit 3 Pumped-storage hydro, 134 MW, 1967
Unit 4 Pumped-storage hydro, 134 MW, 1967
Unit 5 Pumped-storage hydro, 134 MW, 1967
Unit 6 Pumped-storage hydro, 134 MW, 1967
Unit 7 Pumped-storage hydro, 134 MW, 1968
Unit 8 Pumped-storage hydro, 134 MW, 1968
Among Pennsylvania’s plants
Largest plants in the state by nameplate capacity, with the plants ranked next to this one.
- 1Peach Bottom2,876 MW
- 2TalenEnergy Susquehanna2,532 MW
- 3Limerick2,277 MW
- 16Tenaska Westmoreland Generating Station1,134 MW
- 17Moxie Freedom Generation Plant1,105 MW
- 18Muddy Runthis plant
- 19Hickory Run Energy Station1,034 MW
- 20Crane Clean Energy Center981 MW
Other rankings
- All US power plants
- 280th of 14,286
- Power plants in Pennsylvania
- 18th of 273
- Pumped-storage plants in Pennsylvania
- 1st of 2
- Plants in the PJM Interconnection balancing area
- 69th of 2,049
- Plants run by Constellation Power, Inc
- 4th of 17
- Biggest single unit, among Pennsylvania’s plants
- 45th of 273
Operable units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 1 | Pumped-storage hydro | 134 MW | 134 MW | 1967 | Operating |
| 2 | Pumped-storage hydro | 134 MW | 132 MW | 1967 | Operating |
| 3 | Pumped-storage hydro | 134 MW | 134 MW | 1967 | Operating |
| 4 | Pumped-storage hydro | 134 MW | 134 MW | 1967 | Operating |
| 5 | Pumped-storage hydro | 134 MW | 129 MW | 1967 | Operating |
| 6 | Pumped-storage hydro | 134 MW | 128 MW | 1967 | Operating |
| 7 | Pumped-storage hydro | 134 MW | 134 MW | 1968 | Operating |
| 8 | Pumped-storage hydro | 134 MW | 134 MW | 1968 | Operating |
Grid and site
- Balancing area
- PJM Interconnection
- Reliability region
- ReliabilityFirst
- Highest grid connection voltage
- 220 kV
- Water source
- Susquehanna River
- Nearest town on record
- Drumore
- Operator type
- Independent producer
- Coordinates
- 39.808°N, 76.299°W
Closest plants
| Plant | Runs on | Capacity | Distance |
|---|---|---|---|
| Holtwood | Hydroelectric | 247 MW | 2.2 mi northwest |
| Peach Bottom | Nuclear | 2,876 MW | 3.7 mi southeast |
| York Energy Center | Natural gas | 1,449 MW | 4.9 mi south |
| Keystone Solar | Solar | 5 MW | 5.6 mi northeast |
| Safe Harbor | Hydroelectric | 418 MW | 9.4 mi northwest |
| Wildcat Point Generation Facility | Natural gas | 1,114 MW | 9.5 mi southeast |
| Essential Power Rock Springs LLC | Natural gas | 796 MW | 9.6 mi southeast |
| Conowingo | Hydroelectric | 531 MW | 12.3 mi southeast |