Performance analysis and optimization of a novel vehicular power system based on HT-PEMFC integrated methanol steam reforming and ORC

Abstract

In this paper, a novel vehicular high temperature proton exchange membrane fuel cell (HT-PEMFC) power system integrated with methanol steam reforming (MSR) and Organic Rankine Cycle (ORC) is proposed. The system uses waste heat from the HT-PEMFC to provide the MSR subsystem for hydrogen production, and the ORC subsystem recovers the remaining heat to generate electrical power. The thermodynamic model of the system and multi-criteria evaluation are established. Numerical results show that increasing the current density and decreasing the cathode pressure and stoichiometry is favorable for improving the net output power of the system, but also increasing the levelized cost of energy and carbon mass specific emission of the system. Higher operating temperatures and anode pressures are beneficial to overall performance. Moreover, the system is optimized using the NSGA-II algorithm to obtain the three-dimensional (3D) Pareto solution and the optimal set of operating parameters. The optimized system net output power, levelized cost of energy and carbon mass specific emission at the Final Optimal Point are 36.98 kW, 0.2138 $/kWh and 0.5583 kg/kWh, respectively. Compared to the un-optimized system, the system working at optimal parameters has better thermodynamic, economic and environmental performance.