Conowingo — Harford, MD — Operational Power Plant
EIA 860M DataOperational
Total Capacity
530.8 MW
Summer: 496.9 MW | Winter: 572 MW
Technology
Hydro
11 generators
First Unit Online
March 1, 1928
Conowingo is a hydro power plant in Harford County, MD with 11 generating units totaling 530.8 MW of nameplate capacity. It is operated by Constellation Power, Inc. Its first unit came online in 1928.
About this plant
The Conowingo Dam is a large hydroelectric dam in the lower Susquehanna River near the town of Conowingo, Maryland. The medium-height, masonry gravity dam is one of the largest non-federal hydroelectric dams in the U.S., and the largest dam in the state of Maryland. The dam sits about 9.9 miles (16 km) from the river mouth at Chesapeake Bay, 5 miles (8 km) south of the Pennsylvania border and 45 miles (72 km) northeast of Baltimore, on the border between Cecil and Harford counties. The dam is privately owned by the Susquehanna Electric Company, a subsidiary of Constellation Energy.
Source: Wikipedia
Capacity rank
- #47 in the U.S. by capacity
- #1 in MD by capacity
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Monthly generation history
Source: EIA Form 923
Generators (11)
Operational
11 generators
11 operational generators totaling 530.8 MW · online 1928–1964
Plant Information
| Plant ID | 1574 |
| Plant Name | Conowingo |
| Operator | Constellation Power, Inc |
| Sector | IPP Non-CHP |
| Balancing Authority | PJM |
| Power Market | |
| County | Harford |
| State | Maryland (all interconnection requests in Maryland) |
| Status | Operational |
| Generation Type(s) | Hydro |
| Total Nameplate Capacity (MW) | 530.8 |
| Total Summer Capacity (MW) | 496.9 |
| Total Winter Capacity (MW) | 572 |
| Generating Units | 11 |
| Operational Units | 11 |
| Planned Units | 0 |
U.S. county map showing Harford, MD
Data source: U.S. Energy Information Administration EIA Form 860M
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