Kühtai Pumped Storage Power Plant, Austria

Copyright: TIWAG Austria

The additional storage volume increases the flexibility and functionality of the overall system. More available water enables electricity to be produced over a longer period of time; In phases with a lot of generation from solar and wind power, more energy potential is therefore stored in the large lakes at high altitude.

The planned Kühtai storage facility will not only store water for pump circulation. By capturing water in the rear of the Stubai Valley and in the Sulz and Winnebach valleys, an additional 260 million kWh of electricity can be generated from natural inflow alone.

Copyright: TIWAG Austria

Project Facts

Key figures of the Kühtai storage power plant:

Kühtai storage capacity: around 31 million m3.

Kühtai 2 power plant: average capacity of 130 MW in turbine mode and 140 MW in pump mode

Length of the bypass system: around 25 km from the rear Stubai Valley to Kühtai

Catchment area: around 68 km2

Electricity generation from nat. Inflow: 260 GWh / year

The Kühtai 2 power plant, including the headrace, connects the Finstertal and Kühtai reservoirs. The cavern excavated for this purpose is located at a depth of 174 m below the surface. The power plant is designed for combined turbine and pump operation. Up to 90 m3 of water per second will flow through the two machine sets.

The cavern has connections to the outside via an access tunnel and a drainage tunnel. Only the portal of these two tunnels are visible in the area.

Copyright: TIWAG Austria

AFRY's assignment covers the execution design of the main caverns including structural calculations, coordination with EM parts, preparation of formwork and reinforcement drawings and a 3-D coordination model of the main structures of the PSPP. The 3-D Model form the basis for the incorporation of the system in a BIM Model.

The overall schedule for AFRY's services is about 66 months.

“This is a continuation of AFRY's outstanding experience in the development and design of PSPP globally.

“We are very pleased to continue our good co-operation with TIWAG in executing this important project. “

Client: TIWAG – Tiroler Wasserkraft AG

Visit Kühtai Project Website

Did you know?

•         Pumped Storage Power Plants (PSPP), the world’s ‘water battery’, accounts for over 94 per cent of installed global energy storage capacity and retains several advantages such as lifetime cost, levels of sustainability and scale. The existing 161,000 Megawatts (MW) of pumped storage capacity supports power grid stability, reducing overall system costs and sector emissions

•         AFRY is one of the largest hydropower consulting engineering companies globally, ranked No 4 in the ENR Global Sourcebook 2020