Unit 1 at Belgium's Doel nuclear plant automatically shut down on 2 January, just three days after it was restarted following a lengthy outage.
Plant operator Electrabel said: "Everything went according to procedure. There was no impact on safety, and no impact on staff, local residents and the environment." Electrabel added that the reactor went offline due to "normal safety mechanism," so it can restart safely. It is expected to restart again on 6 January.
Belgium's Federal Agency for Nuclear Control (Fanc) had approved the restart of Doel 1 and 2 in late December. Doel 1 was shut down in February 2015 when it reached the end of its 40-year operating life. Doel 2 has been in a maintenance outage since October 2015 and was scheduled to close permanently this month under the same phase-out legislation. However, both units have had their operating licences extended by 10 years until 2025 after Fanc verified that operator Electrabel had completed "priority actions" at the units and that conditions for long-term operation have been met. Doel 1 and 2, both 433MWe pressurised water reactors (PWRs), began commercial operation in February 1975 and December 1975 respectively.
Belgium's Council of Ministers announced in July 2012 that both units would have to close after 40 years of operation. However, in December 2014 the new ruling coalition government agreed to a further 10 years of operation, provided that Electrabel complied with Fanc's new technical safety requirements. In April, Electrabel submitted an integrated action plan to Fanc comprising a list of priority actions to be completed before the units resumed operation and a series of measures to be taken within 3-5 years of the reactors being restarted. This was approved by Fanc in early October.
Under current Belgian law, nuclear power is to be phased out by 2025. At the end of November, Electrabel's parent Engie agreed to pay an annual fee of €20m ($21m) between 2016 and 2025 for the continued operation of Doel 1&2. The fee is to be paid into the energy transition fund. Doel 3 and Tihange 2 look set to close when they reach the end of their 40-year lives in 2022 and 2023, with Doel 4, Tihange 3 and the life-extended Tihange 1 following in 2025.
Doel 3 was restarted on 21 December, Engie said, ending a shutdown that began in March 2014 after unexpected results from tests carried out on the structural integrity of its reactor pressure vessel. The restart of the 1006MWe PWR had been postponed for a week because of issues related to planning and not because of any abnormality with the plant, Electrabel said. Doel 3 was originally taken offline in 2012, along with Tihange 2, because of uncertainties over the structural integrity of their RPVs. In June 2013 the units were restarted, but were shut down again in March 2014 after unexpected results from additional tests. Last month Fanc authorised their restart based on satisfactory results from structural assessments. Tihange 2, a 1008MWe PWR, was restarted earlier in December.