Nuclear plant operator Teollisuuden Voima (TVO) said testing of the Olkiluoto 3 (OL3) nuclear reactor would restart on Tuesday evening.
Test drills at Finland's newest nuclear reactor stopped in October, following the discovery of damage to feedwater pumps that TVO said had "most likely been caused by the test production, where the pumps are used in abnormal circumstances."
During Tuesday's test production, OL3 will generate electricity at an output level of 300-400 megawatts, according to TVO's projections. By Wednesday, output is expected to reach 1,600 megawatts, the reactor's full capacity.
"The week-and-a-half long trial phase will include about ten full capacity tests. During this time output will vary considerably. At times the facility will be disconnected from the national grid," explained TVO spokesperson Johanna Aho.
The reactor is expected to generate an estimated 1.3 terawatt hours of electricity over the trial period.
Regular electricity production is to start on 8 March 2023, according to TVO.
The Olkiluoto 3 project—which had initially been due to start full power electricity production in 2009—has been besieged by problems and setbacks.
The 1.6-gigawatt OL3 will become Finland's fifth and biggest reactor, and is expected to produce around 14 percent of the country's electricity once it is fully operational.
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