Waldshut power plant - The youngest member of the Schluchsee Group
Once the Schluchsee water has passed the Häusern and Witznau power plants on its 600-metre journey into the High Rhine Valley and generated clean electricity, it hits the turbines of the Waldshut pumped-storage power plant. From here, it can flow directly into the power plant’s own High Rhine reservoirs, completing the natural hydrological cycle.
Conversely, Waldshut pumped-storage power plant is the starting point of the storage cascade – the water is transported from the High Rhine along the same route via Witznau and Häusern power plants, which are located higher up, to Schluchsee whenever the huge storage pumps have to relieve the pressure on the power grid.
Witznau and Waldshut pumped-storage power plants are directly connected by a 9.4-kilometre-long underground tunnel that has to meet the highest hydraulic demands. It connects Witznau reservoir as the upper reservoir with the four hydroelectric sets at Waldshut power plant, each consisting of a turbine, a pump and a generator.
Being able to store electricity in large quantities and generate it within seconds when needed is now more important than ever. The sun and the wind have long been playing their part in generating electricity in Germany and are producing an ever increasing share. Yet these generation sources fluctuate depending on the weather and are unreliable. Pumped-storage power plants come into play when too much electricity overloads the grid or a lack of electricity threatens the supply. They work within seconds, produce zero emissions and generate outputs that rank them among the best of all available storage technologies.
How pumped-storage power plants work
Pumped-storage plants consist of an upper and lower basin. Between them are power plants, which pump water uphill if there is excess electricity and allow it to flow down again through turbines to generate electricity when power is needed. They are precisely tailored to meet the needs of the grid at all times. As such, they help to secure the supply – cleanly, effectively and reliably.
With its five pumped-storage power plants, Schluchseewerk AG is one of Germany’s largest suppliers and leading experts. As a partner to its shareholders, it oversees the safe and reliable operation of all its facilities, thereby helping to stabilise the power grid and playing its part in safeguarding the energy supply for today and tomorrow. Schluchseewerk – we are driven by water!
|Construction period:||1942 to 1951|
|Tunnel length:||9.4 kilometres (Rhine Valley Tunnel)|
|Average drop height:||160 metres|
|Average output in turbine mode:||150 megawatts|
|Average output in pump mode:||80 megawatts|
|Upper reservoir||Witznau reservoir|
|Lower reservoir||Reservoirs in the High Rhine and the Aubecken reservoir in Dogern|
Facts and figures
- Average annual generation: approx. 160 million kilowatt-hours of power (enough to cover the annual needs of around 45,000 three-person households)
- Pressure equalisation structure: Eschbach surge tank, standing 160 metres tall with a diameter of 14 metres (making it almost as tall as Ulm Minster)
- Turbine flow rate at full load: 140 cubic metres of water per second (this could fill about 1,200 bathtubs every second)
- Pump flow rate at full load: 40 cubic metres per second