Conowingo

Hydro power plant in Maryland, United States of America. Approximate location 39.6572, -76.1752.

HydroMarylandUnited States of America

Conowingo is a 531 MW hydro power station in Maryland, United States of America. It is operated by Exelon Power. Based on reported annual generation of 2,162 GWh, it can supply roughly 617,685 homes. It ranks #706 of 9,833 United States of America power plants by installed capacity. Commissioned in 1943, it is around 83 years old — an older, legacy facility. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, hydro supplies about 5.3% of United States of America's electricity; the national grid averages 384 gCO₂/kWh (43.0% low-carbon) (2025).

531MW installed capacity
2,162GWh reported / yr
617,685homes powered
1943commissioned (~83 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0001574.

Reported generation trend

2013: 1,699 GWh20132014: 1,595 GWh20142015: 1,598 GWh20152016: 1,369 GWh20162017: 1,935 GWh20172018: 2,788 GWh20182019: 2,162 GWh20193k GWh

Annual generation (GWh), WRI Global Power Plant Database (CC BY 4.0).

Owner

Operated by Exelon Power. All plants by this company →

Local climate & thermal context

This hydro plant converts the energy of falling or flowing water through hydro turbines. It sits in a humid subtropical climate (Köppen Cfa) — Northern Hemisphere, latitude 39.7°N — which shapes how much energy it can produce and how its output varies through the year.

12.1°Cannual mean temp
2,630heating degree-days (base 18°C)
505cooling degree-days (base 18°C)
71 melevation

Monthly mean temperature

J: 0 °CJF: 1 °CFM: 6 °CMA: 11 °CAM: 16 °CMJ: 21 °CJJ: 24 °CJA: 23 °CAS: 20 °CSO: 13 °CON: 8 °CND: 3 °CD24 °C

Heating degree-days here run 7% above the median power plant in this dataset — a proxy for how much extra energy heated equipment must replace through its surfaces in winter.

Climate heat-demand index: 53/100 — this site sits in the mid third of the power plants we cover by heating degree-days.

In colder climates, uninsulated hot equipment (boilers, turbines, valves, steam lines) loses proportionally more heat to ambient air — exactly the loss Inzonex modular insulation is designed to cut.

Climate normals: WorldClim 2.1 (1970–2000 monthly normals, 10 arc-min, CC BY 4.0); zone: Köppen-Geiger world climate classification (Kottek et al. 2006, 0.5° grid). Degree-days & heat-demand index computed by PowerAtlas — a modelled heat-demand proxy, not a measured site figure.

How it compares & nearby plants

The #45 largest hydro power plant of 1449 in United States of America by capacity.

United States of America has 1449 hydro power plants in this dataset, together about 101,657 MW of capacity.

Nearby power plants

Location

Coordinates 39.6572, -76.1752 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

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