A multi-million SEK investment to secure long-term power supply from Oskarshamn 3

Pressrelease Thursday, August 24, 2017

OKG's Board of Directors has decided to invest in a complementary security system at Oskarshamn 3 (O3), a so-called independent core cooling. The system will be completed at some point during 2020 and will amount to a total cost of 865 million SEK. The investment is a fundamental prerequisite for the OKG organisation's ability to secure long-term supplies of weather-independent and fossil-free power from Sweden's largest single production plant.

From December 31, 2020 onwards, it is presumed that Swedish nuclear power reactors meet new increased safety requirements. To secure future power production in these plants, plant owners thereby need to invest in systems that are capable of cooling the fuel core even if all of the ordinary and parallel safety systems fail. Through the investment decisions now taken by OKG's Board of Directions, the prerequisites are in place to ensure long-term production operation for the company.

- Today's investment decision is clear evidence of the owners' confidence in the efficiency improvements we have carried out so far and reflects a confidence in our ability to carry out operations in a safe and effective manner, says CEO Johan Dasht. It is now up to our own abilities to secure the supply of power from O3 through to the 2040s.

Johan underlines that the staffing need however remains unchanged compared with what was agreed to in the context of the conversion process taking place in the light of the decisions taken to phase out the company's two other reactors.

- Thereby, the owners' decision creates a long-term approach which involves greater security for the approximately 600 employees who are required to manage our changed tasks regarding both production and decommissioning. What also paves the way for a bright future is that we, in our key performance indicators regarding operations, have noted positive trends in a number of different areas. It is our systematic improvement process which leads to the organisation performing better and better.

The current investment project itself is a good example of this efficient work. An original design solution has been fine-tuned so that the selected design is both less complex and smaller in size, thereby creating greater freedom of choice when it comes to its location in the plant. In the new solution, the so-called failure filter is also used in order to divert heat created if regular cooling of the fuel core fails. Thereby, a large part of the electrical equipment that was originally included in the design is no longer necessary, which has resulted in a lower investment cost.

- We will therefore be well-equipped to meet all kinds of challenges, concludes Johan Dasht, regardless of whether they are related to competitiveness or safety aspects.

Background information:

In March of 2011, four nuclear power reactors in Fukushima suffered serious failures. These occurred in conjunction with the massive tsunami which affected the eastern coast of Japan. Based on the experiences from these events, so-called stress tests at all nuclear power plants in the EU were carried out. In the light of these, international requirements were revised. Adherence for Swedish nuclear power plants involves needing to implement, by 2020, a complementary safety system which must be able to cool the fuel core if all of the ordinary and parallel cooling systems fail. In the requirements, it calls for the system to be completely independent from ordinary power and water supplies. In the light of this comprehensive set of requirements, OKG has, during the year, secured their design solution with The Swedish Radiation Safety Authority.

If all of the power supply to the reactor's process and safety system would fail at the same time, the high pressure that arises in the reactor tank would be discharged to the so-called condensation pool. At the same time, the heat from the fuel core would be diverted out of the plant via the condensation pool, yet with the help of the existing failure filter. This is so that the discharge is filtered from radioactivity and noble gases.

The independent core cooling system consists of two pumps that are directly driven by a diesel engine. The larger pump starts when the water level in the reactor tank reaches a predefined level. It can replenish the reactor tank in one hour with water from a central pool. The need of water for cooling decreases as the heat in the fuel core drops, and the smaller pump starts after approximately two hours. It cools the core during the remainder of the sequence of events with water from both the central pool and the fire water system and, if necessary, also from a water source in the surrounding area.

Press contact

Johan Dasht

Managing Director

Phone: +46 491-78 75 23

Communications and Public Relations

E-mail: info@okg.uniper.energy

Phone: +46 491-78 75 50

Page updated Thursday, August 24, 2017