Thermal modeling and simulation of a Hydrogen Power Generator

In recent years, the transition toward a sustainable energy system has become one of the major global challenges. Climate change, the increasing demand for electricity, and the need to ensure the security and resilience of energy infrastructures have pushed institutions, governments, and companies to seek alternatives to fossil fuels. In this scenario, hydrogen has gained a strategic role due to its potential as a clean, storable, and flexible energy carrier. This thesis was developed within this context of profound transformation and focuses on the development of hydrogen-based stationary power generation systems, known as Hydrogen Power Generators (HPG). Specifically, the study was conducted at Hitachi Energy, with the aim of providing technical and strategic support to the preliminary evaluations of thermal architectures for the development of a proprietary HPG. The work is divided into two main activities: - a competitive market analysis, aimed at understanding the current landscape of HPG technologies. This includes identifying key players, evaluating the technological solutions they offer, analyzing system sizes, power ratings, and application areas, and comparing performance. This study provides insight into market trends, gaps, and opportunities for the design of competitive hydrogen power solutions; - a thermal simulation phase, aimed at evaluating the thermal architecture of a potential FC-based generator prototype. Simulations are necessary to predict temperature distribution, heat flux, and the overall feasibility of the cooling strategy. The underlying motivations that lead a company like Hitachi Energy to consider entering this sector are multiple. HPGs offer an interesting solution for off-grid or grid-connected and backup or continuous power generation applications in industrial, railway, or civil contexts. Compared to diesel generators, HPGs eliminate local emissions and reduce noise pollution, with the possibility of integration into microgrids or hybrid systems. Despite these advantages, the development of an HPG also poses significant challenges, including the selection of the most suitable FC technology (PEMFC, PAFC, SOFC), the optimization of thermal management, hydrogen supply logistics, and the scalability of industrial production. The simulation results highlight the thermal behavior of the system under different operating conditions. The components temperature profiles are reasonable and close to supplier data, confirming the effectiveness of the cooling strategy. In particular, the heat flux across the heat exchangers shows a stable trend in normal operating conditions, ensuring efficient energy transfer between the working fluid and the environment, while as expected it undergoes de-rating when considering a hotter environment. The transient analysis demonstrates how the system gradually reaches steady-state conditions, where both the temperatures and the heat flux stabilize. These results validate the selected design parameters and provide a solid basis for further optimization. In summary, this thesis aims to offer a concrete and integrated contribution to the technical and strategic evaluation of an emerging technology in a sector destined to play a key role in the decarbonization of energy systems.