Holcomb Rock

Hydro power plant in Virginia, United States of America. Approximate location 37.5035, -79.3006.

HydroVirginiaUnited States of America

Holcomb Rock is a 2 MW hydro power plant in Virginia, United States of America. It is operated by Holcomb Rock Company. Based on its capacity (estimated), it can supply roughly 1,802 homes (estimated). It ranks #8345 of 9,833 United States of America power plants by installed capacity. Commissioned in 1920, it is around 106 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).

2MW installed capacity
1,802homes powered (est.)
1920commissioned (~106 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0056314.

Reported generation trend

2013: 0 GWh20132014: 5 GWh20142015: 6 GWh20152016: 3 GWh20162017: 0 GWh20172018: 0 GWh20182019: 0 GWh20196 GWh

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

Owner

Operated by Holcomb Rock Company. 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 37.5°N — which shapes how much energy it can produce and how its output varies through the year.

13.4°Cannual mean temp
2,225heating degree-days (base 18°C)
549cooling degree-days (base 18°C)
259 melevation

Monthly mean temperature

J: 2 °CJF: 4 °CFM: 8 °CMA: 13 °CAM: 18 °CMJ: 22 °CJJ: 24 °CJA: 24 °CAS: 20 °CSO: 14 °CON: 9 °CND: 4 °CD24 °C

Heating degree-days here run 9% below 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: 47/100 — 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 #1226 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 37.5035, -79.3006 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

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