Through the construction of the pumped storage power plant Reisseck II, VERBUND is not only investing in the expansion of renewable energies but - in connection with the existing power plants Malta and Reisseck - is also creating one of Europe's most efficient hydropower plant groups in Carinthia's Möll Valley.
The high Alpine project area for the pumped storage power plant Reisseck II is located in Mühldorfer Graben at a height of up to 2,300 metres (m) where the Great Mühldorfer Lake will later function as an upper basin. The cavern power plant Reisseck II will be erected 1,585 m above sea level in the mountain and equipped with two powerful pump turbines.
Similar to a normal storage power plant, Reisseck II will produce peak electricity in high demand periods, whereby water will be transported via a works water channel from Great Mühldorfer Lake to the two turbines that drive the generators. The processed water will run into a lower basin.
Both of the machines units in the mountain can be switched to pump operation, whereby the generators will then function as motors and the turbines will pump the water from the lower basin back up to the upper basin. Pump operation will take place during the day when the European grid is carrying more electricity than is required by the consumers. Energy which, for example, comes from the large wind farms or the Danube power plants can be saved in the form of pumped-up water. The pumped storage power plant Reisseck II will therefore function as a "green battery" in the Alps. The power plant will have a capacity of 430 megawatt (MW), both in turbine and pump operation. This corresponds to the electricity generating capacity of approximately 200 wind turbines.
On completion of the rock cavern for the power plant in 2011, the boring of the works water channel to Great Mühldorfer Lake commenced in the first half of 2012 with an 880-ton (t) and 220 m tunnel boring machine. The assembly work on Austria's largest power plant construction site commenced in summer 2012. 300 experts are currently working on this high Alpine site. The newest VERBUND pumped storage power plant Reisseck II will be commissioned in 2014. The total investment volume amounts to € 385 million.