From 28 to 30 July 2025, the Lecco campus of the Politecnico di Milano hosted the International Seminar on Nuclear Reactor Core Thermal Hydraulics Analysis (IS-ReCTHA-2), an international event dedicated to the challenges and perspectives of next-generation nuclear energy, with a particular focus on Small Modular Reactors. The seminar was organized by professors Marco Pellegrini and Stefano Lorenzi from the Department of Energy and brought together experts from universities, research centers, safety authorities, and leading companies in the field from Italy and abroad.

The seminar also featured the award ceremony for Prof. Hisashi Ninokata, recognized for his outstanding contributions to nuclear thermal-hydraulics, his exceptional commitment to training new generations, and his longstanding friendship with Italy and the Politecnico di Milano.

At the heart of the debate was the role of the Italian industry in the nuclear renaissance in the country and in Europe. Keynote talks were delivered by Michele Frignani (Ansaldo Nucleare), Luca Mastrantonio (ENEL), and Alberto Pasanisi (Edison), who outlined the potential contribution of “new nuclear” to national and continental decarbonization. Following this, Matteo Rocco (Politecnico di Milano – Department of Energy) presented a study on the role of nuclear energy in Italy’s energy transition pathways towards 2050.

A crucial part of the discussion focused on safety, including lessons learned from the Fukushima Daiichi accident, presented by Shinya Mizokami (TEPCO), as well as the latest simulation and modeling tools for SMR safety, introduced by Sandia National Laboratories, Canadian Nuclear Laboratories, and GRS. Special attention was devoted to advanced SMR technologies, with contributions from Westinghouse, Hitachi GE, EdF, and Holtec, highlighting progress in passive safety architectures and prospects for implementation in Europe and Italy.

European and international research projects with the participation of the Politecnico di Milano also played a central role. These included SASPAM-SA, coordinated by ENEA and dedicated to SMR safety assessment, and TANDEM, focused on integrating SMRs into hybrid energy systems for decarbonization. Further contributions addressed the development of innovative reactors, such as Lead-cooled Fast Reactors presented by newcleo, as well as regulatory aspects, with perspectives from the U.S. Nuclear Regulatory Commission (presented by Emilio Baglietto, MIT), and from the Dutch and Canadian regulators.