Analytical simulation of rich hydrogen gas - Air Proton Exchange Membrane Fuel Cell system fueled by natural gas

A low temperature Proton Exchange Membrane Fuel Cell (PEMFC) system, fueled by natural gas is proposed and its performance is investigated by establishing a thermodynamic model of integral approach using energy and species mass conservation in addition to chemical and thermal equilibrium and electrochemical principals. Adiabatic cell reactions with temperature changes are assumed. Activation, ohmic and concentration potential losses are considered in cell voltage calculations. Estimate of the cost of electricity (COE) of the proposed system is also made using data fits of the available purchase costs. Computer programs using the Engineering Equation Solver (EES) supported with graphical user interface (GUI) are established for solution. Parametric studies are conducted to this system over ranges of: stack pressure, stack inlet temperature, reformer temperature, gas shift temperature and current density. Output power, electrical efficiency and the COE are calculated to investigate the economically optimum operating range of each input parameter.