TVO permitted to continue to increase the power of OL3

The third unit of the Olkiluoto nuclear power plant was started, in other words, its fuel was made critical for the first time on 21 December 2021.

After the start-up, the low power tests carried out by TVO together with the plant provider showed that the plant is operating as planned. STUK reviewed the test plans, observed the tests on site and reviewed the results. The plant provider is a consortium made up of AREVA GmbH, AREVA NP SAS and Siemens AG.

STUK will continue to observ the power increase and the tests carried out in connection with it on site. The next time TVO will need STUK's permission is when it increases the power of the reactor above 30% of its full capacity. Before that, the plant has already started to produce electricity. STUK will also authorise the increase of the power of the reactor above 60%.