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Caldeirão

Hydro power plant in Guarda, Portugal. Approximate location 40.5317, -7.3296.

HydroGuardaPortugalconventional storage

Caldeirão is a 40 MW hydro power plant in Guarda, Portugal. It is operated by Electricidade dos Açores SA. Based on its capacity (estimated), it can supply roughly 40k homes (estimated). It ranks #60 of 480 Portugal power plants by installed capacity. Commissioned in 1994, it is around 32 years old — long-established. 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).

40Source-backed capacity
40,045homes powered (est.)
1994commissioned (~32 yrs)

Plant data: WRI Global Power Plant Database (CC BY 4.0), id WRI1022568.

Data status

Known data

FacilityCaldeirão WRI
CountryPortugal · Guarda WRI
Coordinates40.5317, -7.3296 WRI
FuelHydro WRI
MW installed capacity40 MW WRI source record; scope not independently normalised
OwnerElectricidade dos Açores SA WRI
Commissioned1994 WRI
Technologyconventional storage WRI

Calculated from dataset

Capacity rank in country#60 of 480 calculated
Fuel-specific rank in country#14 of 122 calculated
Capacity vs country/fuel peers8.51× · 5 MW median · 122 peers calculated
Homes-powered equivalent40,045 calculated
Climate13.0°C · HDD 2,008 derived from coordinates
Environmental severityC3 · 30/100 derived from coordinates

Not available

GWh reported / yrNot available not in dataset
CO₂ emissionsnot applicable not applicable

Known, modelled and calculated values are kept separate. Missing fields are shown as unavailable.

Data provenance

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 L100001054813); fuel: WRI source-record fuel

In context: how this plant compares

At 40 MW, Caldeirão is well above the median hydro plant in Portugal (5 MW). Technically it is described as conventional storage. 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.

Capacity vs largest hydro plants in Portugal

Frades II: 736 MW736Frades IIAlto Lindoso: 630 MW630Alto Lindo…Venda Nova: 90 MW90Venda NovaBelver: 81 MW81BelverRibeiradio: 74 MW74RibeiradioAlto Rabagão: 68 MW68Alto Rabag…Caniçada: 62 MW62CaniçadaVilar-Tabuaço: 58 MW58Vilar-Tabu…

Installed capacity (MW), WRI Global Power Plant Database (CC BY 4.0).

Owner

Operated by Electricidade dos Açores SA.

Local climate & thermal context

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 40.5°N — which shapes how much energy it can produce and how its output varies through the year.

13.0°Cannual mean temp
2,008heating degree-days (base 18°C)
211cooling degree-days (base 18°C)
711 melevation

Monthly mean temperature

J: 6 °CJF: 7 °CFM: 9 °CMA: 10 °CAM: 14 °CMJ: 18 °CJJ: 21 °CJA: 21 °CAS: 18 °CSO: 14 °CON: 9 °CND: 7 °CD21 °C

Heating degree-days here run 18% 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: 43/100 — this site sits in the mid 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.

Site climate & environmental severity

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.

C3ISO 9223 corrosivity (indicative)
30/100environmental-severity index
14.8°Cseasonal temperature swing
122 kmdistance to coast

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.

How it compares & nearby plants

The #14 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.

Nearby power plants

Location

Coordinates 40.5317, -7.3296 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions

What type of power plant is Caldeirão?

Caldeirão is a 40 MW source-record hydro power plant in Guarda, Portugal, commissioned in 1994.

How many homes can Caldeirão power?

Its output is enough to supply roughly 40,045 homes (estimated).

Who operates Caldeirão?

Caldeirão is operated by Electricidade dos Açores SA.

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