A theoretical simulation of flat plate collector performance, with temperature-dependency for material and coolant properties, is presented and the simulation is performed without asserting an a priori value for an overall heat loss coefficient of the collector. This approach differs from many previous works reported in the literature. For a given meteorological condition as well as key design parameters of collector as inputs, the model describes a 2-D absorber plate where its temperature distributions along with the coolant channels can be predicted. A comparison between the theoretical predictions and the experimentally measured data show good agreement to within 4%. The distributed modeling of a collector described in this paper is deemed to be a useful tool for the design of solar collectors. (C) 2002 Elsevier Science Ltd. All rights reserved.