Preparing for repairs in Kaprun

In recent weeks, the Kaprun storage power plant group has suffered two separate technical failures at two different power plants. The manufacturing companies are currently evaluating the causes of the faults. Repair measures are being prepared and preliminary work has begun.

“Evaluating the causes of damage to the affected components is the responsibility of the relevant manufacturers or contract partners of VERBUND. This is being carried out as quickly as possible in close coordination with VERBUND’s experts.Specific repair plans and timetables will be provided to us by our contract partners by the end of November,” said Michael Strugl, CEO of VERBUND. “The other power plants in the Kaprun power plant group, primarily Limberg II and Kaprun Haupstufe, are not affected and are continuing to produce electricity reliably. The security of supply in Austria is not at risk due to the outages.”

Situation at Limberg I power plant (Kaprun-Oberstufe)

In early November, scheduled black start tests at Limberg I power plant resulted in damage to the mains regulating transformer. In order to determine the exact cause of the damage, VERBUND’s contractual partner will arrange for the equipment to be disassembled, removed and sent to a repair workshop within the next two weeks. The transformer is still under warranty.  Despite this damage in Kaprun-Oberstufe, the Kaprun power plant group’s black start capability is still fully assured by the Kaprun-Hauptstufe and Klammsee power plants. 

Limberg III – generator of generator set 2 already removed

Completely separately from this, insulation damage occurred to the rotors of both generator sets during initial operation tests carried out at the new Limberg III pumped storage power plant. To determine the exact causes of damage to the generators, which are still in the commissioning phase, VERBUND’s contracting partner removed and dismantled generator set 2 immediately after its failure. The corresponding repair plan will be submitted to VERBUND for final approval by the end of November. According to VERBUND’s contractual partner, this plan will be based on rapid procurement, production and installation measures so that commissioning can resume and be completed as quickly as possible. A realistic estimate of the duration of the repair works can only be made once the final, detailed damage analysis is available. 

Production stoppages and warranty

Since the detailed damage analyses by the contractual partners are still ongoing, the length of time required for repairs and thus the extent of revenue losses for both power plants have not yet been determined. Monetary impacts cannot be estimated until the repair plans of VERBUND’s contractual partners have been finalised. 

VERBUND Kaprun power plant group

The Kaprun storage power plant group consists of five power plants with a turbine capacity of 902 MW and a pumping capacity of 620 MW. This includes the pumped storage power plant Limberg I (Kaprun-Oberstufe, 160 MW turbine and pumping capacity) and Limberg II (480 MW turbine and pumping capacity). The newly built Limberg III pumped storage power plant (480 MW turbine and pumping capacity) is currently at commissioning stage.

The Kaprun-Hauptstufe storage power plant with a turbine capacity of 260 MW, in conjunction with the Klammsee storage power plant, also provides system services such as black start capability for the Austrian transmission system, in addition to peak power generation.