Analysis of H2 production with zero carbon emissions from an integrated multi-energy system

In this study, a novel system was designed and analyzed experimentally by integrating 8 integrated panels of flat-plate photovoltaic thermal (FP PV/T) producing 1600 W and 2 series connected proton exchange membrane (PEM) electrolyzer to produce green hydrogen, electrical and thermal energy. The numerical model was established for FP PV/T driven PEM electrolyzer and physical model was investigated for key factors to analyze the efficiency and performance of the proposed system. Experimental analysis shows that the temperature and current density play a key role in the production and efficiency of the electrolyzer. However, increasing the FP PV/T temperature also affects electrical efficiency negatively, and the effect of applied current density is larger as compared to inlet temperature. For the membrane thickness of 300 μm, PEM electrolyzer showed the best performance. In simultaneous heat and hydrogen production mode of novel system, the overall solar energy utilization efficiency, hydrogen production efficiency, hydrogen production capacity, and thermal efficiency were 25.52%, 10.01%, 1299.33L, and 15.51% respectively. The system was validated and the relative errors in hydrogen production efficiency, photovoltaic electrical efficiency, electrolyzer efficiency, and hydrogen production were 7%, 1.4%, 5.8%, and 5.8%, respectively. The economic analysis shows that the novel system needs additional equipment as compared to conventional solar powered PEM electrolyzer, which increases the initial cost however it proves to be more economical in the longer time span and returns its value in 5 years. The experimental results show that the model can be implemented as a standalone system to fulfill energy needs, or it can be considered as a prototype for energy and hydrogen production on the large scale.