In Finland, the Olkiluoto nuclear power plant is preparing to resume the operation of its third reactor in test mode after an issue with internal components of the feed pumps was identified. The restart is planned for December 27, a timeline reported by Reuters. This pause followed a maintenance period during which engineers inspected and confirmed the integrity of critical systems before reintroducing the unit to a controlled testing phase that verifies performance under near-operational conditions.
The Olkiluoto-3 unit is then scheduled to enter full normal operation on March 8 the following year. The transition from test mode to steady generation is a carefully staged process that requires validation of safety systems, heat transfer performance, and grid synchronization to ensure stable supply to the national network. Operators monitor turbine response, cooling performance, and emergency shutdown readiness as part of the commissioning plan, with milestone checks that align with regulatory requirements and utility safety standards.
The issue with the feed pumps was detected on October 19. While officials stated that the malfunction did not pose a danger to staff or the surrounding environment, it caused a delay in bringing the third reactor to its intended level of production. A thorough assessment was conducted to identify the root cause, followed by corrective actions designed to prevent recurrence. The incident underscores the importance of robust maintenance programs and rapid containment strategies in handling components that are essential to reactor cooling and power conversion systems.
Olkiluoto NPP plays a critical role in supporting Finland’s industrial sector, including the operation of local pulp and paper mills that rely on a stable and continuous electricity supply. The plant’s new reactor obtained its operating license on March 7, 2019, reflecting a long process of design review, safety certification, and regulatory approval. The power unit was connected to the electricity grid in a controlled trial mode on March 13, 2022, marking a significant milestone in the modernization of Finland’s clean energy capabilities and its commitment to reducing fuel imports through domestic generation capacity.
Separately, regional energy news reported that the Kozloduy Nuclear Power Plant in Bulgaria halted a unit due to generator cooling issues. The stoppage impacted output from that plant and prompted inspections aimed at safeguarding plant integrity and grid reliability. While the event is unrelated to the Finnish unit’s restart schedule, it highlights how commissioning, maintenance, and cooling system performance are common focal points across European nuclear facilities as they balance reliability, safety, and economic considerations. Industry stakeholders track such developments to understand how each plant’s operational readiness translates into regional energy security and market stability.