This paper compares the performance of three different solar based technologies for a stand-alone power supply (SAPS) using different methods to address the seasonal variability of solar insolation-(i) photovoltaic (PV) panels with battery storage; (ii) PV panels with electrolyser and hydrogen (H-2) storage; and (iii) photoelectrolytic (PE) dissociation of water for H2 generation and storage. The system size is determined at three different Australian locations with greatly varying latitudes-Darwin (12 degrees S), Melbourne (38 degrees S) and Macquarie Island (55 degrees S). While the PV/electrolyser system requires fewer PV panels compared to the PV/battery scenario due to the seasonal storage ability of H2, the final number of PV modules is only marginally less at the highest latitude due to the lower energy recovery efficiency of H2 compared to batteries. For the PE technology, an upper limit on the cost of such a system is obtained if it is to be competitive with the existing PV/battery technology. (c) 2006 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.