Techno-Economic Modelling of Sustainable-Hydrogen Filling of Fuel Cell Cars 2021-01-0744

A model is presented to simulate the production, storage, and dispensing of hydrogen under different conditions and demands. It entails modeling four main processes: production of hydrogen by electrolysis, its compression by an electrochemical process, a high-pressure storage, and a fuel-cell car-dispensing system. The Proton Exchange Membrane (PEM) electrolysis model is based on an equivalent circuit to compute the electric energy needed for a certain demand of hydrogen. A thermal model is integrated to determine the operating temperature during the electrolysis. The second phase of the model deals with the compression of hydrogen using an electrochemical compressor whose operating advantages are highlighted and compared to a mechanical compressor. A thermal model is also integrated to the compression process. Modeling the storage of the high-pressure reservoir and hydrogen dispensing are based on fundamental thermodynamics; change in internal energy is studied to determine temperature, then pressure is deduced using the Redlich-Kwong equation of state. The dispensing sub-model involves pressure boosting and precooling subsystems to allow fuel cell cars to perform a fill of their tanks for a wide range of initial pressures. Finally, the integration of all sub-models is carried out using smart control of the precooling system based on a lookup table of the initial pressures in the reservoir and the car tank, which would enable automated filling within the safety limits of the tank.