PV/T solar collector is an energy system designed to provide both thermal and electrical energies at the same time. In this paper, the dynamic simulation of a photovoltaic thermal collector is presented. The effect of different parameters, such as meteorological, design and optical parameters are investigated. Furthermore, evaluation and comparative economic analyses among different designs of PV/T sheet-tube collectors, conventional thermal solar collector and PV module is conducted under Monastir (Tunisia) climatic conditions. Numerical results show that the thermal and electrical efficiencies significantly depend on the studied parameters. It is also found that, in terms of economy, the uncovered PV/T collector yield the best performance among others. (C) 2014 Elsevier Ltd. All rights reserved.