Polymer Electrolyte Membrane Fuel Cells for maritime applications: state of art of the technology, experimental assessment of a 240-kW system, and Response Surface Methodology application to data analysis

Hydrogen energy technology allows the production of electricity from hydrogen and backward to store large amounts of energy by converting electricity into hydrogen, using a fuel cell, an electrolyzer, and a hydrogen storage system. The fuel cell market is increasing, offering components with improved converting performances; the expansion of this market and the spread of hydrogen system applications are bringing down the industrial costs of such technology offering new opportunities for commercial applications. This work concerns the Polymer Electrolyte Membrane technology, giving a complete overview of opportunities and problems that may arise from the employment of this type of system for maritime applications. The starting point of the analysis follows a more theoretical approach. Performance and degradation issues have been deeply investigated through thorough literature analysis, to issue the main problematics that can appear in the real operation of the PEM fuel cell system. In this context, a degradation map has been drawn, which can help the prediction of voltage degradation linked to the poisoning of the cell components. Therefore, since the external parameters that can influence the FC performance are highlighted, a statistical approach is investigated to understand how the reactants' flow rates and the thermal control can affect the performance. This has been possible thanks to the employment of the software Design Expert. In the second part of the Thesis, a more experimental approach to the thematic of PEM fuel cell systems for maritime applications is faced. This has been possible thanks to the test campaign carried out on the HI-SEA system, a 240-kW system located in the IES Laboratory of the University of Genoa (Savona Campus), made up of eight Polymer Membrane Fuel Cell modules supplied by Nuvera. This is one of the few complete and existing real-size laboratories for the assessment of PEMFC technology for maritime applications. The laboratory activities are part of the collaboration between the University and Fincantieri, the main Italian shipbuilder. The system has undergone a commissioning phase, which is accurately described, where previous issues are analyzed, understood, and solved to optimize the control system. Therefore, despite a prolonged inactivity time, the PEM fuel cell stacks have been reactivated thanks to a dedicated and innovative procedure. Finally, the system is fully operative: the results of the whole system operation confirm its suitability for operation in a ship-likely environment.