The removal of the four steam generators at Germany’s closed Grafenrheinfeld NPP is underway. PreussenElektra GmbH, a subsidiary of the German utility company E.ON, owns and operates the Grafenrheinfeld plant, which was shut down in 2015 as part of Germany’s nuclear phase-out and is now undergoing dismantling.
The single unit Grafenrheinfeld NPP, a 1,275 MWe pressurised water reactor, in Bavaria was commissioned in 1981. Following Germany’s decision to phase out of nuclear energy in the wake of the Fukushima disasted, Grafenrheinfeld was shut down in 2015. Before its closure, the plant generated 333 TWh of electricity – enough to supply Bavaria with electricity constantly for almost four years.
The dismantling of the Grafenrheinfeld plant began in April 2018 and is expected to take roughly 15 years to complete. In 2020, all fuel elements were moved to an on-site interim storage facility and in August 2024, both 143-metre-tall cooling towers were demolished in a controlled blast. The resulting 55,000 tonnes of concrete rubble are being used to fill the towers’ collection basins to create more storage space for further dismantling activities. The internal components of the Reactor Pressure Vessel (RPV) have already been removed.
PreussenElektra applied for the decommissioning and first dismantling permit for Grafenrheinfeld in 2014 and received it in 2018. PreussenElektra split the application for the individual dismantling scopes into two steps. The dismantling of the plant began in April 2018 with the granting of the decommissioning and dismantling permit. The second dismantling permit, which was applied for in 2019, was granted in December 2022 and includes the dismantling of the reactor pressure vessel and the biological shield surrounding it.
The first of the four steam generators has now been detached from its installation position inside the reactor building. It was gradually lifted, tilted and rotated several times before being set down in front of the new control area closure. This process was particularly challenging because, as the first removal, the space within the reactor building was very limited. Planning for removal of the steam generators began in 2021 and required some structural changes to be made in and around the reactor building.
“This task required the highest precision and impressive engineering skills. Thanks to months of preparation, the actual lifting process could be carried out smoothly in about nine hours,” said Project Manager Burghard Lindner. “Our experienced partners Framatome and Mammoet, who have already removed the four steam generators at the Unterweser NPP, mastered this challenge well.”
The 20-metre-high and 365-tonne steam generator will be removed and made available for transport. Removal of the remaining three components will follow. It is planned to complete the operation by the end of February.
In Spring 2027, the steam generators will be shipped to EDF subsidiary Cyclife in Sweden, dismantled on site and then partially melted down. In 2021, Cyclife which specialises in NPP decommissioning and waste management, was awarded the contract by PreussenElektra for the dismantling and disposal of 12 steam generators from the Unterweser, Grafenrheinfeld and Grohnde NPPs.
