A computer-simulation model of the behaviour of a photovoltaic (PV) gas-turbine hybrid system, with a compressed-air store, is developed in order to evaluate its performance Lis well as predict the total energy-conversion efficiency and the incurred cost under various operating conditions. This integrated PV and gas-turbine hybrid plant produces approximately 140% more power per unit of fuel consumed compared with corresponding conventional gas-turbine plants. In addition, lower rates of pollutant emissions to the atmosphere per kWh of electricity generated are achieved. (C) 2003 Elsevier Ltd. All rights reserved.