For the sustainable production of clean H-2, it is essential to optimize the capture and conversion of renewable energy. In this context, this paper presents a new technique to maximize the efficiency of a photovoltaic conversion system supplying an electrolyzer. Simple, efficient and low cost maximum power point tracking algorithms to optimize energy production are proposed for the three DC/DC electronic converter topologies typically used in photovoltaic and H-2 applications. The method is based on energy balance concepts and exhibits certain analogies with maximum power tracking algorithms extensively used in wind turbines that do not require measurement of the primary energy source. The algorithm provides a reference to the current controller only requiring measurement of electrical variables and solar array temperature. The current controller is implemented using sliding mode strategies. Experimental and simulation results are provided showing the effectiveness and simplicity of the proposed method. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.