In this paper, an integrated combined system of a photovoltaic (glass-glass) thermal (PV/T) solar water heater of capacity 200 1 has been designed and tested in outdoor condition for composite climate of New Delhi. An analytical expression for characteristic equation for photovoltaic thermal (PV/T) flat plate collector has been derived for different condition as a function of design and climatic parameters. The testing of collector and system were carried out during February-April, 2007. It is observed that the photovoltaic thermal (PV/T) flat plate collector partially covered with PV module gives better thermal and average cell efficiency which is in accordance with the results reported by earlier researchers. (C) 2008 Elsevier Ltd. All rights reserved.