Fundamental Modeling of a PEM Fuel Cell Integrated System: Experimental Validation and Multiobjective Optimization
Pradip Sugriv Nande, Amiya K. Jana
Abstract
Polymer electrolyte membrane fuel cells (PEMFC) are an emerging renewable energy resource with wide applications, like in mobile, electric vehicle, airplane, and space research. This work aims at designing an integrated PEMFC system that maximizes efficiency and minimizes cost. With this goal, the fundamental model is developed for a PEMFC integrated with relevant auxiliary units, namely, a compressor, a cooler, a humidifier, and supply and return manifolds. It incorporates fluid flow, electrochemical reaction, and thermal behavior. Validating the model with transient experimental data, it is used for analyzing PEMFC behavior and extended to employ for optimization. A multiobjective optimization problem is formulated with hybridizing the technique for order of preference by similarity to ideal solution and a genetic algorithm first time for PEMFC to optimize the design and operating parameters against two conflicting objectives, stack electrical efficiency and power production cost (PPC), for which a new cost model is introduced. For a hydrogen purchase cost of $5/kg, the optimal PEMFC achieves an average efficiency of 55.3% (against the reported efficiency of 52.21%) with the lower heating value (LHV) and 46.6% with the higher heating value (HHV). PPC is reduced to 0.30–0.32 $/kWh, almost identical for both the LHV and HHV, against reported costs of 0.30–0.31 $/kWh, with a hydrogen purchase cost of 4.55–4.62 $/kg for the HHV.