A comprehensive study of the behaviour of a large-scale, integral-type, natural-circulation solar-energy dryer suitable for use in the tropics has been performed over the entire range of weather conditions encountered in a typical tropical climate. The design, construction and installation of the dryer and its measured transient performance are reported. Linear correlations of measured data for a grouped parameter of ambient and crop properties against moisture content is obtained which may form the basis for the development of solar dryer design charts.