Pracana dam

Pracana dam
	location
Coordinates	39 ° 33 '54 " N , 7 ° 48' 44" W Coordinates: 39 ° 33 '54 " N , 7 ° 48' 44" W.
country	Portugal
place	Mação County , Santarém District
Waters	Ocreza
Height upstream	114 m
	power plant
owner	Companhia Portuguesa de Produção de Electricidade (CPPE)
operator	Energias de Portugal (EDP)
construction time	1947 to 1950
Start of operation	1950
	technology
Bottleneck performance	41 megawatts
Average ; height of fall	28 to 57 m
Expansion flow	88 m³ / s
Standard work capacity	63.8 million kWh / year
Turbines	Francis turbines : 2 × 8 MW, 1 × 25 MW
Generators	2 × 9.68 MVA, 1 × 28.5 MVA
	Others

The Pracana dam ( Barragem de Pracana in Portuguese ) is located in the central region of Portugal . It dams the river Ocreza , a right (northern) tributary of the Tejo to a reservoir (port. Albufeira da Barragem de Pracana ). The Ocreza forms the border between the districts of Santarém and Castelo Branco at this point . A little downstream from the dam, the Ocreza flows into the Tejo. To the south of the Pracana dam is the Fratel dam , which dams the Tejo. The A23 motorway runs between the Tagus and the Pracana reservoir . The nearest town is Gardete , which lies between the two dams on the A23.

The project to build the dam began in 1947 (or 1944). The construction was completed in 1950 (or 1951). The dam is used to generate electricity. It is owned by the Companhia Portuguesa de Produção de Electricidade (CPPE).

Barrier structure

The barrier structure is a concrete pillar dam with a height of 60 m above the foundation base. The top of the wall lies at a height of 115 m above sea level . The length of the top of the wall is 245.5 (or 255) m. The volume of the structure is 144,000 (or 129,000) m³. On the upstream side, a concrete spur reaches 5 m into the rock.

The dam wall has both a bottom outlet and a flood relief . A maximum of 52 m³ / s can be discharged via the bottom outlet, and a maximum of 2,560 m³ / s via the flood discharge. The design flood is 3,500 m³ / s; the probability of this event occurring has been determined to be once in 1,000 years.

Reservoir

With the normal storage target of 114 m, the associated reservoir extends over an area of around 5.5 km² and holds 111.9 (or 116.5) million m³ of water - 69 (or 69.3, 95.6) of this or 102) million m³ are used. The minimum congestion destination at which the machines can still be operated is 97 m. With the usable 95.6 million m³ of water, 9.8 million kWh can be generated.

power plant

With an installed capacity of 40 (or 41) MW, the Pracana power plant is one of the smaller hydropower plants in Portugal . The average annual generation is 61.8 (or 41, 51 or 63.8) million kWh . It is used to cover the peak load .

machinery

Three Francis turbines with a vertical shaft and different capacities are installed. You are in a machine house at the foot of the dam. The following table gives an overview:

machine	Nominal speed (1 / min)	Turbine (MW)	Generator (MVA)	Transformer (MVA)
1	375	8th	9.68	20th
2	375	8th	9.68	20th
3	272.7	25th	28.5	30th

The nominal voltage of the generators is 6 (machine 1 and 2) or 6.3 (machine 3) kV . In the switchgear , the respective generator voltage is raised to 63 kV by means of power transformers.

Global Energy Observatory states that in 1950 three machines with a maximum output of 13.5 MW each were put into operation. According to this source, the installed capacity at the time of commissioning in 1950 was only 14.7 MW.

The minimum height of fall is 28 m, the maximum 57 m. The maximum flow rate for turbines 1 and 2 is 18 m³ / s each, for turbine 3 it is 52 m³ / s.

The power plant went into operation in 1951 (or 1950) and was renovated in 1993. It is owned by the CPPE but operated by EDP .

Web links

Commons : Pracana dam - collection of images, videos and audio files

BARRAGEM DA PRACANA E FRATEL. Youtube, accessed September 17, 2014 (Portuguese).

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Pracana Informação Técnica. EDP , accessed November 16, 2014 (Portuguese).
↑ ^a ^b ^c ^d ^e Pracana dam. Structurae International Database for Structures and Civil Engineers, accessed November 15, 2014 .
↑ ^a ^b ^c ^d PRACANA DAM. APA Barragens de Portugal, accessed November 15, 2014 .
↑ PRACANA. APA Barragens de Portugal, accessed September 16, 2014 .
↑ ^a ^b ^c DECLARAÇÃO AMBIENTAL 2012. (PDF 16.1 MB p. 52 (50)) EDP , accessed on November 16, 2014 (Portuguese).
↑ ^a ^b ^c ^d Hidroelectricidade em Portugal memória e desafio. (PDF 226 KB p. 29 (27)) Rede Eléctrica Nacional, SA (REN), accessed on November 16, 2014 (Portuguese).
↑ ^a ^b ^c ^d ^e Pracana Hydroelectric Power Plant Portugal. Global Energy Observatory, accessed November 15, 2014 .

[EDP-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Pracana Informação Técnica. EDP , accessed November 16, 2014 (Portuguese).

[str-2] Pracana dam. Structurae International Database for Structures and Civil Engineers, accessed November 15, 2014 .

[APA-3] PRACANA DAM. APA Barragens de Portugal, accessed November 15, 2014 .

[APA_2-4] PRACANA. APA Barragens de Portugal, accessed September 16, 2014 .

[da-5] DECLARAÇÃO AMBIENTAL 2012. (PDF 16.1 MB p. 52 (50)) EDP , accessed on November 16, 2014 (Portuguese).

[ren-6] Hidroelectricidade em Portugal memória e desafio. (PDF 226 KB p. 29 (27)) Rede Eléctrica Nacional, SA (REN), accessed on November 16, 2014 (Portuguese).

[geo-7] Pracana Hydroelectric Power Plant Portugal. Global Energy Observatory, accessed November 15, 2014 .