česky english deutsch <<< >>>


Hydroelectric power station, pumped-storage equipment

Ing. Karel Kosek, the executive officer of Zemský úřad (central administration) in Prague came up with the idea to build a hydroelectric pumped-storage power station under Černé jezero (Black Lake) around the year 1920. The idea was later taken up by Ing. František Alexej Pech who produced the project documentation – construction project planning at all levels. In 1928 Západočeské elektrárny (the Western Bohemia Power Company) decided to go ahead with this construction and in June 1928 Ing. František Alexej Pech, the project engineer, in fourteen days surveyed the area for the purpose of the project; he used a three-kilometre-long polygon along the whole track of the future pipeline, and the 274 m high slope with the drop of elevation up to 1:2 was surveyed through the method of tachymetric levelling. The general plan was finished in the autumn 1928, in November the same year it was approved by the water management authority and so detail execution plans and expected budget could be prepared in full. In May 1929 the Civil engineering company Nejedlý and Řehák was commissioned to do all building and construction jobs, and the Škoda Works to deliver all technological equipment and pipelines. The construction of this ambitious power plant in these uneasy natural conditions lasted for just a year and three quarters and cost 10 million CZK. Waters of the Úhlava river were at the beginning taken through the building site in a wooden channel; once the base outlet of 2000 mm calibre was finished, the water went in the pipeline of this outlet as typical of dam constructions. Concreting the dam started from the left bank. The power station was put in operation on the 6th of December 1930. The incoming pipeline 1266 m long from Černé jezero (Black Lake) to the pressure relief chamber is built from cast iron socket tubes sealed with lead of 800 mm calibre and with the flow rate 800 l/s. The pressure channel is 1007 m long and built from steel flange tubes of 560 – 600 mm calibre (the thickness of the wall of the pressure relief chamber is 6 mm, and with the increasing drop of elevation enlarges one mm by one mm up to 15 mm at the power station). The pressure relief chamber is made of iron-concrete, the diameter of its circle cross section is 4 m and it is 12.0 m high over the ground.. The power station alone is situated on the left bank of the Úhlava river in the axis of the dam sufficiently enough protected against big waters. It has one Pelton turbine unit installed, the flow rate 800 l/s at the drop of elevation 247.7 m, the diameter of the wheel is 850 mm, the number of revolutions 750 /min., two jets, regulation with needles, and the over-speeding is also prevented. The Pelton turbine was made by the Škoda Works in Pilsen. On the shared shaft with the turbine is a Škoda motor generator with the output 1500 kW (the power demand in the motor regime is 1750 kW), the output voltage 6 000 V is transformed into 22 000 V (2.5 MVA) to go to the high voltage distribution network. Another machine on the shared shaft is a six-grade centrifugal pump which at that time was the most powerful pump of this type in the country. The diameter of the impeller is 800 mm, the max suction height is 4.7 m. The remarkable pressure height of the pump when we take into account pressure losses is 283.50 m. The pump at its max output flows back 400 l/s through the pipeline to Černé jezero (Black Lake).

Useful information

Česká pošta, (Czech Post) s.p., Hojsova Stráž (phone no. 376 390 120), MO – FR: 13:00 – 16:00

Lékařská ordinace (Medical surgery) Železná Ruda (phone no. 376 397 312), MO, TH: 7:30 – 17:00, TU,WED,FR: 7:30 – 12:00,

Městská Policie (City Police) Železná Ruda (phone no. 602 437 686)

Hasiči (Firemen) Hojsova Stráž (phone no.606 312 870)

Hasiči (Firemen) Železná Ruda (phone no. 724 347 596)

Lékárna (Pharmacv) Železná Ruda (phone no. 376 397 032), MO – FR: 8:00 – 12:00, 13:00 – 17:00

Sběrný dvůr (Waste collection tip) Železná Ruda, WED: 14:00 – 18:00, SA: 8:00 – 12:00

Auto – pneu servis (Car and tyre service) Dalibor Řehulka, Špičák 138 (phone no. 605 803 685)

Odtahová služba (Tow service), nákladní doprava (Freight transport) KS Kontejner (Container) (phone no. 725 809 030)

GPS position

N 49° 11.077', E 13° 11.824'



Město Železná Ruda
Milan Kříž