This paper proposes a new and more efficient device for energy transfer over melting ice with performance improved to produce chilled air by complete removal of melt in cool thermal discharge systems. The maximum temperature gradient on the free surface with complete removal of melt in cool thermal discharge systems has a positive influence on energy transfer rate, and hence the application of this concept to design cool thermal discharge systems is technically and economically feasible. Energy equations have been formulated for calculating the thickness of the ice melted and the thermal penetration distance in the ice layer region. The mathematical formulation of cool thermal discharge systems from ice melting with complete removal of melt has been investigated and the approximation solution has been derived with integral boundary-layer analysis, The equations for estimating the required mass flow rate of the ambient air to produce chilled air were derived from an analysis of the heat transfer coupled with the energy balance. Numerical examples with different inlet ambient air temperatures have been illustrated to simulate practical systems, and hence the time histories of the air mass velocity and the outlet temperature of chilled air have been also delineated. (C) 2002 Elsevier Science Ltd. All rights reserved.