The DELISA-LTO project, funded by the Horizon Europe programme (2022-2026), is making significant strides in ensuring the safe long-term operation (LTO) of Water-Water Energetic Reactors (VVER). This collaborative initiative, involving nine institutions from five countries—Czech Republic, Slovakia, Hungary, Ukraine, and Finland—aims to extend the operational life of VVER reactors for an additional 40 years without compromising safety.
Focusing on critical phenomena such as thermal ageing and swelling, the project is assessing the impact of LTO on VVER reactor components through experimental measurements and advanced modelling techniques. Key components, including the Reactor Pressure Vessel, Reactor Internals, and Steam Generator Tubes, have been identified as particularly vulnerable to degradation during extended operations. The Reactor Pressure Vessel, in particular, is irreplaceable and prone to thermal and irradiation embrittlement, making its maintenance vital to the safety and reliability of nuclear power plants (NPPs).
Through cutting-edge simulation tools and experimental studies, the DELISA-LTO project is developing predictive models to ensure the continued safety of VVER reactors during extended lifetimes. These efforts include the study of steel thermal ageing, advanced Non-Destructive Testing (NDT) techniques, and a comprehensive early-warning system to assess material integrity.
By integrating interdisciplinary approaches and ensuring that critical infrastructure remains operationally safe, the DELISA-LTO project contributes to Europe’s goals of reducing greenhouse gas emissions through sustainable energy production.
