Both units at Finland’s Loviisa NPP are now operating after undergoing extended outages for modification and improvement work to increase their net capacity to 507 MWe. The two VVER-440 pressurised water reactors supplied by Russia began commercial operation in 1977 and 1981.Their original design net capacity was 420MWe. Unit 1 returned to commercial operation on 18 October after an annual outage of around 26 days. Unit 2’s 47-day outage ended on 21 September. A number of safety improvements were implemented including improvements to critical safety functions, maintenance work on the main generators and the replacement of generator stators.
In May 2014 plant owner/operator Fortum and Rolls-Royce signed an agreement for modernisation of the most critical safety automation systems on both units. Fortum created the safety automation architecture based on Fortum's overall plant safety design concept ADLAS, which validated the safety functions with the advanced process simulator APROS, the company said on 25 October. Rolls-Royce was responsible for the design, licensing, installation and commissioning of the new safety systems.
Fortum said the work was completed on time and within budget. The operating licence for Loviisa 1 is valid until 2027 and Loviisa 2 until 2030. The scope of work for Rolls-Royce included design, licensing, installation and commissioning activities for new safety systems. The modernisation work was implemented in three phases during annual outages over the last two years. Fortum said the work was “the most challenging” outage work in the Loviisa station’s history, both in terms of workload and complexity.
Magnus Forsstrom, automation modernisation project owner at the Loviisa power plant, said the nuclear-specific challenge, related to the complexity of licensing processes, “was turned into a success factor throughout the excellent cooperation between Fortum, Rolls Royce and all other stakeholders. This was achieved through an extensive pre-planning phase, proactive schedule management and continuous improvement during the project”. In 2017 the plant produced more than 10% of Finland’s total electricity.