This paper analyzes a new low-temperature electrolysis hydrogen production system using molybdenum-oxo catalysts in the cathode and a platinum bared anode. A thermodynamic model is developed for the electrolysis process in order to predict and analyze the energy and exergy efficiencies. The new electrolysis system with molybdenum-oxo catalysts consists of two half cells of PEM (proton exchange membrane) and alkaline electrolysis. The effects of temperature and membrane thickness are reported at varying current densities. The results are presented and compared with previous studies to demonstrate the promising performance of the system. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.