Litostroj manufactures impellers for Austrian Rosshag power plant

Litostroj Power of the ENERGO-PRO Group will produce four impellers for the Austrian Rosshag pumped-storage hydropower plant. The contract also includes the development of the hydraulic design and model tests in the hydraulic laboratory. Thanks to the contract, Litostroj Power has won its eighth contract from the Austrian power company Verbund Hydro Power.

Litostroj Power, which manufactures turbines and other hydropower equipment in Ljubljana, Slovenia, together with Litostroj Engineering in Blansko, Czech Republic, and other sister companies, form the industrial pillar ENERGO-PRO, a multinational operator of hydroelectric power plants. "We are further strengthening our industrial pillar. We appreciate the fact that we are becoming a stable supplier of our solutions for such an important client as Austrian Verbund. We see this further contract as recognition of Litostroj's creative and reliable approach," said Pavel Váňa, CEO of the ENERGO-PRO Group.

Litostroj Engineering will be in charge of the hydraulic design of the impellers and of the tests in the hydraulic laboratory in Blansko for the Rosshag power plant while Litostroj Power will be in charge of the manufacture of the impellers in Ljubljana and the final delivery of the turbine.

Head like two Eiffel Towers

The Rosshag pumped-storage power plant with four 65-megawatt Francis turbines is located in the Ziller Valley in Tyrol. The water head from the Zillergründl dam reaches 640 metres, which is equal to the height of ten Prague’s Petřín lookout towers or about two Eiffel towers. Rosshag is thus approaching the parameters of the neighbouring Häusling power plant, which boasts the world record of 744 metres – the highest water head in the world that uses a Francis turbine impeller.

Litostroj Power had previously won a contract at the Häusling power plant to modernize its two turbines. The turbines then received new impellers in 2019 and 2020 thanks to the cooperation of engineers in Blansko and Ljubljana. The Rosshag and Häusling power plants are located in the same valley, just a few kilometres apart.

Litostroj Power is currently also implementing four other projects for Verbund – Malta Oberstufe, Limberg I, Töging and Ottensheim—Wilhering.

Technical data

Turbine type

Maximum Output

Maximum water head

Maximum flow rate

Rotational speed

Impeller outer diameter        


4 x 65 MW

640 m

13.3 m³/s

750 min-1

1980 mm