Ybbs-Persenbeug: Final round for the power plant revitalisation

As part of the refurbishment of Austria's oldest Danube power plant at Ybbs-Persenbeug, this winter will see the complete replacement of the last of a total of six machine sets. After the modification, an additional 77 million kilowatt hours of hydroelectricity can be extracted from the Danube. In total, the more than 1.4 billion kilowatt hours generated in the modernised power plant will be enough to supply around 400,000 households.

The mighty size of the plant requires extraordinary equipment. The first task is to drain the machine under the Danube before the actual replacement can be started. 

The dam beams are the key elements when preparing to replace the machines in Ybbs. To withstand the masses of water in the Danube requires strong steel elements weighing 20 tonnes and more. These in turn can be transported only by the floating crane "DOKW2". This waterborne vehicle is owned by VERBUND and can transport loads of up to 80 tonnes and is the only crane of its kind on the Danube. To ensure that the dam beams sit tightly, divers have to go about 15 metres under water. At the foot of the power plant, they manually clean sand and gravel from the support surface and check whether the dam beam is sitting properly. This laborious work can only be done by touch because the murky Danube water obscures the divers' sight. The dam beams themselves are picked up by the floating crane and lowered centimetre by centimetre in to the precisely matching slots in front of the turbine. That requires good coordination between the team, controller and crane operator. 

In the coming days, the decommissioned turbine will be pumped out and the machine set fully disassembled. Parts of the new turbine are already in the power plant and will be completed on site. The challenging works will continue into the spring of 2022.

Electricity from hydropower for generations to come

By investing more than €144m in the project, the revitalisation of all six machine sets will increase generation by more than 77 million kilowatt hours (kWh) to a total of 1.4 billion kWh and further improve reliability. The six old Kaplan turbines will be replaced, the instrumentation and control system improved. This efficiency increase of 6% corresponds to the annual electricity consumption of 22,000 households.
The measures at the existing Ybbs-Persenbeug power plant will – without having to make structural interventions in the surrounding area – enable the generation of electricity from hydropower to increase significantly and thus save an additional 62,000 tonnes of CO2 emissions every year.