Registry, engineering, and operating metrics shown on a consistent EIA basis.
| Metric | Conowingo Harford County | Seneca Generation LLC Warren County |
|---|---|---|
| Capacity | 530.8 MW | 437.9 MW |
| Technology | Conventional Hydroelectric | Hydroelectric Pumped Storage, Conventional Hydroelectric |
| Operator | Constellation Power, Inc | Seneca Generation LLC |
| Operating units | 11 | 3 |
| Latest 12-month generation | 1.68 TWh | -344.9 GWh |
| Latest complete-year capacity factor | 33.3% (2025) | — |
| National technology rank | #26 of 1,349 | #16 of 39 |
| Latest EIA report | 2026-04 | 2026-04 |
Generation comes from EIA-923. Capacity, unit counts, technology, and reporting relationships come from EIA-860. Incomplete reporting years are excluded from capacity-factor comparisons.