Maranhão is a 6 MW hydro power plant in Portalegre, Portugal. Based on its capacity (estimated), it can supply roughly 6.1k homes (estimated). It ranks #264 of 480 Portugal power plants by installed capacity. Commissioned in 1958, it is around 68 years old — an older, legacy facility. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, hydro supplies about 29.7% of Portugal's electricity; the national grid averages 128 gCO₂/kWh (81.0% low-carbon) (2025).
Plant data: WRI Global Power Plant Database (CC BY 4.0), id WRI1022733.
Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.
The capacity and fuel fields on this page are source-record values from the upstream open dataset. They are useful for identification and ranking, but they have not been upgraded to a 2026 registry/GEM-location verified value.
capacity: WRI Global Power Plant Database source-record (legacy); fuel: WRI source-record fuel
At 6 MW, Maranhão is well above the median hydro plant in Portugal (5 MW). 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.
Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).
This hydro plant converts the energy of falling or flowing water through hydro turbines. It sits in a hot-summer Mediterranean climate (Köppen Csa) — Northern Hemisphere, latitude 39.0°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 53% 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: 28/100 — this site sits in the bottom 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 moderately corrosive environment (estimated ISO 9223 class C3 — Medium), with humidity / wetness 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 #52 largest hydro power plant of 122 in Portugal by capacity.
Portugal has 122 hydro power plants in this dataset, together about 2,718 MW of capacity.
Coordinates 39.0152, -7.9756 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.
Maranhão is a 6 MW source-record hydro power plant in Portalegre, Portugal, commissioned in 1958.
Its output is enough to supply roughly 6,106 homes (estimated).
