en.Wedoany.com Reported - Fortum is implementing a major turbine island modernization at the Loviisa nuclear power plant, scheduled to be completed in phases during the annual outage periods from 2026 to 2028. Upon completion, the plant's electrical power output will increase by approximately 38 megawatts (MWe), and electricity generation over its entire lifetime will rise by about 7 terawatt-hours (TWh). This project is part of a EUR 1 billion (USD 1.15 billion) lifetime extension investment program aimed at ensuring the plant continues to provide stable, fossil-free electricity through 2050. The project is led by Fortum's in-house experts and implemented together with selected partners.
The Loviisa nuclear power plant consists of two Soviet-designed VVER-440 reactors and currently supplies more than 10% of Finland's electricity. Unit 1 entered commercial operation in 1977, and Unit 2 in 1981. Preparatory work for this modernization includes rotor cleaning and inspection, and the overall effort is structured around three base projects targeting the plant's conventional island area rather than the nuclear island.
The low-pressure turbine refurbishment is being carried out by Doosan Škoda Power of the Czech Republic, delivering the 38 MWe electrical output increase directly without requiring additional heat from the reactors. The work involves replacing all eight low-pressure turbine inner casings and internal flow components across both units. To minimize raw material waste and control costs, the structurally sound large outer casings and existing steam valves are being retained and refurbished, then structurally integrated with new steam-aerodynamically optimized internal flow components. After the upgrade, the plant's expected lifetime electricity generation under the extended operating license will increase from 170 TWh to 177 TWh. Equipment delivery and physical modification began in August 2026 during the scheduled annual outage.
The turbine automation upgrade is being handled by Finnish technology supplier Valmet. The turbine protection and control systems are undergoing a comprehensive technology transition to replace obsolete third-party legacy systems that have reached the end of their operational life. Valmet is installing its proprietary Valmet DNA turbine automation system on four separate steam turbine sets, replacing more than 16,000 physical interface signals, all routed through a modern distributed digital control network. The new user interface provides operators in the two main control rooms with expanded real-time data, high-fidelity monitoring, and digital diagnostics for generator auxiliary systems. In April 2026, Valmet delivered an identical comprehensive digital training simulator hardware and software package to help control room operators master the new automation operations before the actual systems are commissioned. System testing and handover will first take place at Reactor 2 in October 2026, followed by Reactor 1 in October 2028.
The main seawater pump replacement is being carried out by Andritz of Austria. The main cooling infrastructure will be renewed to stabilize the secondary circuit thermal cycle of the conventional island. These industrial pumps draw cold Baltic Sea water directly into the plant's large condensers, cooling the steam leaving the low-pressure turbines back into water so it can be safely pumped back into the power generation circuit. Each of the two Loviisa units relies on four main seawater pumps in a redundant array, for a total of eight pumps across the plant. The original Soviet-era pumps and electric motors have reached the end of their technical life, and Andritz is installing custom vertical long-shaft or split-case cooling water pumps featuring hydraulic impeller blade adjustment and corrosion- and wear-resistant coatings suited to the brackish marine environment.
The upgrade is integrated with the annual outage maintenance to minimize impact on generation and make efficient use of resources. The 2026 outage is divided into two separate and consecutive phases, ensuring one reactor unit remains in operation while the other is being serviced. Unit 2, undergoing a comprehensive eight-year overhaul, is out of service from August 2 to September 21; the two units will then be temporarily online or in transition for a few days to balance grid load. Unit 1 follows a standard shorter maintenance window focused primarily on refueling, with an outage from September 26 to October 18. To carry out this work, the plant has brought in 1,000 external contractor workers from approximately 100 specialized engineering companies.
The logistics of transporting the newly upgraded low-pressure turbine components to the Loviisa site require careful coordination. The complete set of components to be replaced weighs approximately 2,000 tonnes, with heavy lifting operations broken down into specific modular assemblies. The turbine inner casings and new flow components are manufactured at the Doosan Škoda Power plant in Pilsen, Czech Republic, then transported via dedicated heavy-duty multi-axle trailers along Czech and German motorways to strategic northern German ports such as Hamburg or Rostock, where they are transferred to heavy cargo vessels for the Baltic Sea crossing, sailing directly to the dedicated industrial quay at the Loviisa site on Hästholmen Island.
Because the upgrade is tied to the plant's annual maintenance outages, there is no buffer time for delivery delays. Components must arrive, pass quality assurance, and be positioned on site before the outage sequence begins. To avoid congestion at the island's quay space, components are first systematically managed at an onshore secondary transshipment port, and only transferred to the island once the turbine hall is physically ready.
Once components enter the turbine hall, logistics shift to precise positioning. The heavy lifting team uses the turbine hall's main overhead gantry crane to hoist and lower the new internal assemblies. Since Fortum is retaining and refurbishing the original massive outer casings to save costs, engineers must seamlessly install the brand-new Western-designed internals into the Soviet-era shells, requiring micron-level alignment to prevent microscopic imbalances that could trigger dangerous turbine vibration.
As new components come in, old ones must be moved out, triggering a secondary logistics cycle. The eight original worn low-pressure inner casings must be carefully unbolted, cut into manageable sections, and lifted out of the turbine hall. These components operate entirely in the conventional island (non-nuclear side) and are not radioactive. Clearing thousands of tonnes of legacy industrial steel requires a dedicated transport fleet to move the metal off the island and deliver it to domestic recycling facilities.
