Alto Rabagão Dam () is a

concrete Concrete is a composite material composed of aggregate bound together with a fluid cement that cures to a solid over time. It is the second-most-used substance (after water), the most–widely used building material, and the most-manufactur ...

dam on the Rabagão River, a left tributary of the

Cávado River The Cávado River (, ) is a river located in northern Portugal. It has its source in Serra do Larouco at an elevation of above sea level. It runs from Fonte da Pipa, near the triangulation station Larouco, to its mouth into the Atlantic Oce ...

. It is located in

Peneda-Gerês National Park Peneda-Gerês National Park (, ), also known simply as Gerês, is a national park in Norte Region, Portugal. Created in May 1971, it is the oldest protected area and the only national park in Portugal. It covers an area of , occupying the Distric ...

, in the municipality

Montalegre Montalegre (), officially the Town of Montalegre (), is a municipality in northern Portugal, located in the district of Vila Real, along the border with Spain. The population in 2011 was 10,537, in an area of 805.46 km². History Early con ...

, in

Vila Real District The District of Vila Real ( ) is a district of northern Portugal. With an area of , the district is located east of the port city of Porto and north of the Douro, Douro River. Vila Real has always belonged to the historical province of Trás- ...

Portugal Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...

. Construction of the dam began in 1957. The dam was completed in 1964. It is owned by ''Companhia Portuguesa de Produção de Electricidade'' (CPPE). The dam is used for power production.

Dam

Alto Rabagão Dam is a 94 m tall (height above foundation) and 1,970 m long

dam, which is composed of an

arch dam An arch dam is a concrete dam that is curved upstream in plan. The arch dam is designed so that the force of the water against it, known as hydrostatic pressure, presses against the arch, causing the arch to straighten slightly and strengtheni ...

in the center and

gravity dam A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation. Gravity dams are designed so that each section of the dam is ...

s on both sides. Its crest altitude is 880 m. The volume of the dam is 1,117,000 m³. The dam contains a crest

spillway A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure tha ...

with 2 gates (maximum discharge 500 m³/s) and a bottom outlet (maximum discharge 360 m³/s).

Reservoir

At full reservoir level of 880 m (maximum flood level of 880.1 m) the reservoir of the dam has a surface area of 22.12 km² and its total capacity is 568.69 mio. m³. Its active capacity is 557.92 (550 or 550.1) mio. m³. Minimum operating level is 829 m. With the 550.1 mio. m³ water 973.1 GWh can be produced.

Power plant

The

pumped-storage Pumped-storage hydroelectricity (PSH), or pumped hydroelectric energy storage (PHES), is a type of hydroelectric energy storage used by electric power systems for load balancing. A PSH system stores energy in the form of gravitational potent ...

hydroelectric Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other Renewable energ ...

power plant went operational in 1964. It is owned by CPPE, but operated by EDP. The plant has a

nameplate capacity Nameplate capacity, also known as the rated capacity, nominal capacity, installed capacity, maximum effect or gross capacity, (72) MW. Its average annual generation is 85.2 (83 95 or 97) GWh. The power station is located downstream and contains 2 reversible

Francis turbine The Francis turbine is a type of water turbine. It is an inward-flow reaction turbine that combines radial and axial flow concepts. Francis turbines are the most common water turbine in use today, and can achieve over 95% efficiency. The pro ...

-generators with 36.75 MW (45 MVA), each in an

underground powerhouse An underground power station is a type of hydroelectric power station constructed by excavating the major components (e.g. machine hall, penstocks, and tailrace) from rock, rather than the more common surface-based construction methods. One or mo ...

. The turbine rotation is 428 rpm. The minimum

hydraulic head Hydraulic head or piezometric head is a measurement related to liquid pressure (normalized by specific weight) and the liquid elevation above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22, eq.3.2a. It is usually meas ...

is 129 m, the maximum 185 m. Maximum flow per turbine is 25.7 m³/s. When pumping, each of the pumps has a maximum energy consumption of 31.7 MW and can pump 18 m³/s. The pumps are operated independently of the Francis turbines. As lower reservoir for Alto Rabagão the reservoir of Venda Nova Dam is used.

References

{{DEFAULTSORT:Alto Rabagao Dam Dams in Portugal Pumped-storage hydroelectric power stations in Portugal Arch dams Dams completed in 1964 Energy infrastructure completed in 1964 1964 establishments in Portugal Buildings and structures in Vila Real District Reservoirs in Portugal Underground power stations

Dam

Reservoir

Power plant

See also

References