Modeling for optimal operation of PEM fuel cells and electrolyzers

This contribution presents and analyzes modeling and minimum cost operation of proton exchange membrane (PEM) fuel cells and electrolyzers. First, detailed thermoelectric models of the electrochemical technologies based on a first-principle approach are presented. Then, as the detailed nonlinear models developed are intractable for use in online optimal control computation, a mixed integer linear program (MILP) is formulated with a piecewise affine approximation of the conversion efficiency and linear temperature dynamics for the devices. The outputs of the simplified linear models are compared with the detailed ones, when optimally producing and consuming a fixed quantity of hydrogen gas. Comparisons are performed for a variety of price scenarios and efficiency approximations, for both the fuel cell and electrolyzer.