Teollisuuden Voima Oyj (TVO) company announced that Unit 3 of Finland's Olkiluoto 1600 MWe nuclear power plant was connected to the national grid on 12 March and has started supplying electricity. Unit 3 attained first criticality on 21 December. On 12 March, the unit was connected to the grid at a power output of 103 MWe. Olkiluoto Unit 3 is the first nuclear power plant commissioned in Finland after more than four decades. The test phase will last about four months, and will be followed by the unit's power output being gradually increased to 100%.