Decommisioning of Barsebäck and Oskarshamn Nuclear Power Plants – status and results

The Energy Company Uniper is the owner of Sydkraft Nuclear Power, Sweden. Uniper is responsible for decommissioning of the two Barsebäck nuclear power units B1 & B2 located across from Copenhagen on the west coast of Sweden, as well as for the Oskarshamn units O1 & O2 situated on the Swedish east coast.

Barsebäck unit B1 closed in 1999 and unit B2 in 2005, while Oskarshamn O2 closed in 2015 (after 2,5 years of outage), and unit O1 in 2017. O1 was the first commercial NPP in Sweden and the smallest of the four. B1, B2, and O2 are triplets, meaning that their design is almost identical.

Oskarshamn unit O3 is still in operation with a planned end of life in 2045.

A strategy work performed in 2017-2018 was a unique endeavor as it evaluated various scenarios for the decommissioning of the four units. The chosen one was to combine all four units in an integrated fleet approach, a strategy that was both innovative and proved very efficient.

This selected scenario, known as the Sequence Scenario, was designed to tackle the critical and more complex work packages in a full combined sequence for all 4 units, ensuring a smooth and systematic process. This IDA event will go into detail as to how, why, and what lessons were learned, as well as how recycling and resource management were implemented and executed from the start.

The scheduled total duration for the radiological dismantling work and the planned free release of the sites is a testament to the strategy's effectiveness, namely totaling 10 years – making this unique for nuclear power plant dismantling globally.

In combination with the pragmatic Nordic regulatory framework, this fleet approach has enabled the D&D program to aim to be THE international benchmark for cost- and exposure-efficient dismantling.