In this paper, a hybrid Photovoltaic (PV)-fuel cell generation system employing an electrolyzer for hydrogen generation is designed and simulated. The system is applicable for remote areas or isolated loads. Fuzzy regression model (FRM) is applied for maximum power point tracking to extract maximum available solar power from PV arrays under variable insolation conditions. The system incorporates a controller designed to achieve permanent power supply to the load via the PV array or the fuel cell, or both according to the power available from the sun. Also, to prevent corrosion of the electrolyzer electrodes after sunset, i.e. when its current drops to zero, the electric storage device is designed so as to isolate the electrolyte from the electrolysis cell. (C) 2002 Elsevier Science Ltd. All rights reserved.