GROSIO is a 737 MW hydro power station in Lombardy, Italy. It is operated by A2A SpA [100%]. Based on reported annual generation of 1,184 GWh, it can supply roughly 338k homes. It ranks #56 of 489 Italy power plants by installed capacity. Commissioned in 1960, it is around 66 years old — an older, legacy facility. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, hydro supplies about 15.8% of Italy's electricity; the national grid averages 285 gCO₂/kWh (48.8% low-carbon) (2025).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id WRI1002891.
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
The public capacity above is a source-verified 2026 capacity claim: 737 MW for Grosio hydroelectric plant.
Source: GEM tracker raw 2026. Scope: operating/nameplate; source-backed GEM tracker 2026 plant record. Confidence: high_source_row_verified_strict.
The capacity and/or fuel fields on this page include a source-backed provenance label from GEM, an official registry, Wikidata, OSM, or a cross-source match.
capacity: GEM tracker 2026 (location L100000602208); fuel: WRI source-record fuel
At 737 MW, GROSIO is well above the median hydro plant in Italy (132 MW). Technically it is described as run-of-river. Hydropower converts the energy of falling or flowing water into electricity; output depends on rainfall and reservoir level, and large dams also provide grid balancing and storage.
Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.
Annual generation (GWh), WRI Global Power Plant Database (CC BY 4.0).
Operated by A2A SpA [100%].
This hydro plant converts the energy of falling or flowing water through hydro turbines. It sits in a polar tundra climate (Köppen ET) — Northern Hemisphere, latitude 46.3°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 135% 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: 98/100 — this site sits in the top third of the power plants we cover by heating degree-days.
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.
For a plant’s outdoor hardware — heat-recovery steam generators (HRSG), expansion joints, valves, flanges and their insulation — the local climate sets how fast unprotected steel and coatings degrade. This site sits in a benign, low-corrosion environment (estimated ISO 9223 class C1 — Very low), with thermal cycling the leading environmental stress.
Higher environmental severity is exactly where protective removable insulation pays back most: a sheltered micro-climate slows corrosion, UV and thermal-cycling damage and extends outdoor hardware service life. This is an indicative site-climate context — not a condition assessment of any specific plant or operator.
Indicative estimate via the ISO 9223:2012 informative method (atmospheric corrosivity from temperature, time-of-wetness and airborne salinity), using WorldClim climate normals, the Köppen-Geiger class and coast distance. Indicative, not a measured corrosion rate.
The #5 largest hydro power plant of 58 in Italy by capacity.
Italy has 58 hydro power plants in this dataset, together about 13,593 MW of capacity.
Coordinates 46.286, 10.2653 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
GROSIO is a 737 MW source-record hydro power plant in Lombardy, Italy, commissioned in 1960.
GROSIO generates about 1,184 GWh of electricity per year.
Its output is enough to supply roughly 338,314 homes.
GROSIO is operated by A2A SpA [100%].
