Nestled in the mountain ranges of the Hohe Tauern at the foot of Austria’s highest mountain, the Grossglockner, the Mooserboden, Wasserfallboden, Margaritze and Klammsee reservoirs are fed by the Pasterzen glacier and other mountain streams.
The Kaprun Oberstufe/Limberg 2 pumped storage power plant pumps water from the lower Wasserfallboden reservoir into the Mooserboden reservoir and converts the power of this water back into electrical energy as required, thus supplying valuable balancing and control energy for the power grid.
Security of the energy supply
The impressive dam walls of the Kaprun high mountain reservoirs and the intelligent combination of reservoirs with storage and pumped storage power plants make the Kaprun power plant group an important element of Austria’s energy supply.
Around 50% of the water stored in the Mooserboden and Wasserfallboden reservoirs and used for electricity generation in the Kaprun Upper Stage and Kaprun Main Stage power pants comes from the south of the Alps; most of it is meltwater from the Pasterzen glacier of the Großglockner.
Water from the lower-lying Wasserfallboden reservoir can be pumped into the Mooserboden reservoir by the pumps in the Kaprun upper level power plant.
| Owner | VERBUND Hydro Power GmbH |
|---|---|
| Operator | VERBUND Hydro Power GmbH |
| Commissioning | 1956 |
| Type | Pumped-storage power plant |
| Country | Austria |
| Region | Salzburg, Carinthia |
| Waters | Salzach, Kapruner Ache |
| Output | 593 MW |
| Annual output | 152,092 MWh |
| Turbine | Francis |
| Connectivity | No fish bypass |
The final level of the Mooserboden storage facility is 2,036 m above sea level. The topographical situation required two damming structures for the storage facility: the Mooser dam and the Drossen dam. The final level of the Wasserfallboden storage facility is located at an elevation of 1,672 m above sea level and includes the damming structure, the Limberg dam.
The powerhouse was built entirely on rock at the foot of the Limberg dam. Two sets of machinery with horizontal shafts (two Francis turbines) and a total bottleneck capacity of 112 MW (without auxiliary sets of machinery) are installed in the powerhouse. Each set of machinery comprises a Francis turbine, a motor generator, a gear coupling and a two-stage, double-flow pump. 110 kV indoor switchgear was installed in the powerhouse. The energy is conducted via a 110 kV double-circuit transmission line to the Kaprun open-air switchgear.
Limberg II, the “green battery”, represents the most significant expansion of the Kaprun power plant group since the commissioning of the upper stage in 1956. Two caverns, a power cavern and a transformer cavern were built underground in the rocks. Two vertically installed pump turbines, each with an intake capacity of 72 m³/sec, deliver 240 MW of valuable peak energy each during pumping and turbine operation.
