Techno-economic analysis of polymer electrolyte membrane fuel cell system configurations

Abstract

The major constraints restricting wide-spread commercialization of fuel cell systems are both technical and economical. Many researchers have designed polymer electrolyte membrane (PEM) fuel cell system configurations, which are different in terms of energy utilization and cost. Therefore, it is imperative to determine the best system configuration in order to produce efficient and economically viable PEM fuel cell systems. This paper reports an exergy and economic analyses conducted on five different PEM fuel cell system configurations with a view to assess their performance. Thermolib – a tool box for MATLAB/Simulink designed for modelling and simulation of energy systems was used to model and simulate the operation of each of the systems (5 kW stack power, 40 cells and 0.25m2 active membrane area) and data obtained was used for the exergy analysis. It was found that largest exergy loss occurred in the fuel cell stack (over 90%). The overall exergy and energy efficiencies of the studied systems were between 24.23% to 30.18% and 47.77% to 59.48%, respectively. A hybrid PEM fuel cell system configuration was proposed and analyzed. It was found to have an overall exergy and energy efficiencies of 31.95% and 62.97%, respectively. The return-on-investment evaluated for each of the five studied PEM fuel cell system configurations as well as the proposed system configuration were 1–27% while the payback periods were 3–13 yrs. The proposed system configuration was found to have the best performance in terms of energy utilization and had the lowest cost per kilowatt net power.