In the present study the series combination of N PVT water collectors, partially covered with photovoltaic module, in two different configurations namely case A: Photovoltaic module at lower portion; case B: Photovoltaic module at upper portion, have been analyzed. Analytical expressions for instantaneous thermal efficiency and temperature dependent electrical efficiency have been derived. The performances of both configurations have been compared on thermal efficiency basis and temperature dependent electrical efficiency basis. It has been concluded that at moderate mass flow rate, for large number of PVT water collectors connected in series both cases give nearly same results. (C) 2015 Elsevier Ltd. All rights reserved.