This paper investigates how to improve the fuel efficiency of an anodic dead end mode fuel cell for portable power generation Generally, a periodic purge process in anodic dead end operation is required to avoid anode flooding caused by back diffusive water from the cathode However during the purge process small amounts of the hydrogen are discharged with the water lowering the fuel utilization efficiency Therefore hydrogen pulsations are introduced and experimental attempt to minimize the purge frequency is conducted in this study The experimental results indicate that pulsation reduces partial pressure of the water vapor in the anode channel, increasing the interval between purges by approximately three times thus improving overall efficiency (C) 2010 Professor T Nejat Veziroglu Published by Elsevier Ltd All rights reserved