The simple empirical relation is developed to estimate the glass cover temperature for known values of water and ambient temperatures in basin type hybrid (PV/T) active solar still. The empirical relation developed is based on outdoor experimental results of water and ambient temperature in the range of 14 degrees C to 92 degrees C, and 14 degrees C to 36 degrees C respectively. The results obtained for glass cover temperature using proposed relation are validated with the experimental as well as using a numerical results (obtained by numerical solution of heat balance equation) of solar still. The proposed glass cover temperature is obtained with a maximum relative error of 1.12% compared to the value obtained through a numerical solution. The maximum relative error in evaporative mode of energy transfers from water surface is obtained as 1.2%. (C) 2009 Elsevier B.V. All rights reserved.