CASTRO II is a 195 MW hydro power station in Castille and Leon, Spain. It is operated by IBERDROLA GENERACION S.A.. Based on reported annual generation of 182 GWh, it can supply roughly 52,085 homes. It ranks #85 of 872 Spain power plants by installed capacity. Commissioned in 1977, it is around 49 years old — long-established. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, hydro supplies about 11.4% of Spain's electricity; the national grid averages 154 gCO₂/kWh (74.6% low-carbon) (2025).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id WRI1006321.
Annual generation (GWh), WRI Global Power Plant Database (CC BY 4.0).
Operated by IBERDROLA GENERACION S.A.. All plants by this company →
This hydro plant converts the energy of falling or flowing water through hydro turbines. It sits in a warm-summer Mediterranean climate (Köppen Csb) — Northern Hemisphere, latitude 41.6°N — which shapes how much energy it can produce and how its output varies through the year.
Monthly mean temperature
Heating degree-days here run 5% 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: 48/100 — 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.
The #24 largest hydro power plant of 124 in Spain by capacity.
Spain has 124 hydro power plants in this dataset, together about 15,659 MW of capacity.
Coordinates 41.5756, -6.1891 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
