This article presents and discusses the results of an exergy analysis conducted during the operation of a test-bed hybrid wind/solar generator with hydrogen support, designed and constructed at the Industrial Engineering School of the University of Extremadura, Badajoz (Spain). An exergy analysis is made of the different components of the system, calculating their exergy efficiencies and exergy losses, and proposing future improvements to increase the efficiency of the use of the surplus energy produced by the wind/solar generator. The results show the electrolyzer to have an acceptable efficiency (eta(ex) = 68.75%), but the photovoltaic modules a low exergy efficiency (eta(ex) = 8.39%) as also is the case, though to a lesser extent, for the fuel cell (eta(ex) = 35.9%). Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.