Miranda Dam

Miranda Dam
Location of Miranda Dam in Portugal
Official name	Barragem de Miranda
Location	municipality Miranda do Douro, Bragança District, Portugal
Coordinates	41°29′19″N 6°15′56.2″W
Status	Operational
Construction began	1955
Opening date	1961
Owner(s)	Companhia Portuguesa de Produção de Electricidade
Dam and spillways
Type of dam	Concrete buttress dam
Impounds	Douro
Height	80 m (260 ft)
Length	263 m (863 ft)
Dam volume	240,000 m^3 (8,500,000 cu ft)
Spillway type	Over the dam
Spillway capacity	11,000 m³
Reservoir
Total capacity	28,100,000 m^3 (22,800 acre⋅ft)
Active capacity	6,660,000 m^3 (5,400 acre⋅ft)
Surface area	1.22 km^2 (0.47 sq mi)
Power Station
Operator(s)	Energias de Portugal
Commission date	Miranda I: 1960 Miranda II: 1995
Hydraulic head	Miranda I: 66 m (217 ft) (max) Miranda II: 60 m (200 ft) (max)
Turbines	Miranda I: 3 x 58.84 MW Francis-type Miranda II: 193 MW Francis-type
Installed capacity	Miranda I: 180 MW Miranda II: 189 MW
Annual generation	Miranda I + II: 897.8 GWh

Miranda Dam (Portuguese: Barragem de Miranda) is a concrete buttress dam on the Douro, where the river forms the national border line between Spain and Portugal. It is located in the municipality Miranda do Douro, in Bragança District, Portugal.

Construction of the dam began in 1955. The dam was completed in 1961. It is owned by Companhia Portuguesa de Produção de Electricidade (CPPE).[1]

Dam

Miranda Dam is an 80-m-tall (height above foundation) and 263-m-long buttress dam with a crest altitude of 535 m. The volume of the dam is 240,000 m³. The dam contains 4 crest spillways (maximum discharge 11,000 m³/s) and one bottom outlet.[1]

Reservoir

At full reservoir level of 528.05 m (maximum flood level of 533 m) the reservoir of the dam has a surface area of 1.22 km^2 and its total capacity is 28.1 mio. m³ (active capacity 6.66 mio. m³).[1]

Power plant

The power plant went operational in 1960. It is a run-of-the-river hydroelectric power station. It is owned by CPPE, but operated by EDP.[2] The plant has a nameplate capacity of 369[3][4] (390)[1][2] MW. Its average annual generation is 897.8[3] (879[4] or 1,036.3[1][2]) GWh.

Miranda I

The power station contains 3 Francis turbine-generators with 58.84 (67)[2] MW each in an underground powerhouse. The turbine rotation is 150 rpm. The minimum hydraulic head is 51 m, the maximum 66 m. Maximum flow per turbine is 128 m³/s.[3]

Miranda II

In 1995 an additional underground powerhouse was completed and a further Francis turbine with a 193 MW capacity went online. The turbine rotation is 100 rpm. The minimum hydraulic head is 40 m, the maximum 60 m. Maximum flow of the turbine is 386 m³/s.[3]

See also

• List of power stations in Portugal

References

1. "MIRANDA DAM". APA Barragens de Portugal. Retrieved 2015-02-05.
2. "Miranda Hydroelectric Power Plant Portugal". Global Energy Observatory. Retrieved 2015-02-05.
3. "Miranda Informação Técnica" (in Portuguese). Energias de Portugal. Archived from the original on 2014-11-03. Retrieved 2015-02-05.
4. "DECLARAÇÃO AMBIENTAL 2012" (PDF) (in Portuguese). Energias de Portugal. pp. 29–30 (27–28). Archived from the original (PDF) on 2014-11-03. Retrieved 2015-02-05.