Modernisation of the Braunau-Simbach power plant

VERBUND is revitalising the hydropower plant with the energy transition in mind. The Braunau-Simbach power plant, consisting of four vertical Kaplan turbines with three-phase synchronous generators, was constructed in the years 1951 to 1954. Due to the plant’s age and the condition of the original turbines and generators as well as the electrical ancillary facilities, extensive refurbishment measures are needed over the coming years. Initial preparatory work is expected to begin in December this year, with the gradual replacement of the machine components scheduled to take place between autumn 2024 and the end of 2028. The total investment runs to 80 million euros.

Replacement of the turbines and generators

The main part of the work involves the installation of four new, ultramodern Kaplan turbine impellers and generators. The turbine replacement will demand maximum precision from the team working in the power plant. An impeller alone weighs 58 tonnes and has a diameter of 6.3 metres. The improved efficiency of the turbines and a planned increase in the expansion water quantity from 1,070 to 1,260 m³/s will enable generation to be increased by 11.8% following completion of the project and authorisation under the Water Act. Thus an additional 65 million kilowatt hours per year will be generated there in future. That corresponds to the annual power consumption of 18,500 households. In total, once the refurbishment is complete, the Braunau-Simbach power plant will be generate 615 kilowatt hours and thus supply 175,000 households with green electricity generated from hydropower.

The remaining machine components and key electrical system parts, such as transformers and switchgear, have also reached the end of their service life and need to be partially refurbished or replaced. Due to the size of the plant, storage areas are needed near to the powerhouse for the removal of existing components and the delivery of new ones.

Additional space for office, accommodation and sanitary containers is also needed for the engineers and fitters who will be needed to work on site. Initial visible measures include the carrying out of felling and clearing work near the power plant site. These areas will be used on a temporary basis for the aforementioned storage and container areas. They will be reforested following completion of the revitalisation work. The cycle path will remain fully open during the construction work.

With the revitalisation of the Braunau-Simbach power plant, VERBUND is continuing the maintenance and expansion activities at its power plants on the Inn. Thanks to the extensive modernisation works, VERBUND is making a valuable contribution to securing the sustainable energy supply, with an additional saving of around 25,000 tonnes of CO2 per year.

Modernisation phases at the Braunau-Simbach power plant:

• Q4 2023 - Q1 2024 Clearing of the necessary areas (temporary)
• Q4 2023 - Q2 2024 Gantry crane refurbishment
• Q1 + Q2 2024 Assembly of the crane track extension
• Sept. 2024 - April 2025 Renewal of Machine 2
• Sept. 2025 - April 2026 Renewal of Machine 4 and Block 4 (*)
• Sept. 2026 - April 2027 Renewal of Machine 3 and Block 3 (*)
• Sept. 2027 - April 2028 Renewal of Machine 1 and Block 1 (*)
• Sept. 2028 - Dec 2028 Renovation of Block 2 (*)
  
  

(*)    Includes the renewal of the block transformer, 110 kV switchgear, generator diversion and the medium-voltage switchgear