Fuel utilization factor challenges in theoretical and experimental approaches

In the Polymer Electrolyte Membrane (PEM), high purity hydrogen (about 99%) is typically employed as the input of the anode and the remaining part of the hydrogen is recycled to the entrance of the anode via a reversible hydrogen cycle. Nevertheless, this reversible process has a lot of unsolved control problems, such as high price. By the purpose of solving these problems and maximizing the security and efficiency in these systems, the amount of the fuel should be reduced for a determined output power. In addition to, it is crucial that the fuel consumption can be reduced in a cell, without add an extra step for the hydrogen reversing, to improve the energy efficiency of these systems.