The majority of coal burned in Indian power stations is high-ash, nln-of-mine coal that has been subjected to little or. no coal beneficiation to reduce its ash and sulfur content. This article considers each stage of the supply chain of coal from the coal mine to electricity generation in evaluating costs for the supply of power station fuels. The question of whether or not to wash mined coal prior to combustion is fundamentally addressed. Three cases of coal preparation are considered and the relative economics of all mine-to-electricity costs examined in order to establish a set of guidelines for determining the extent of beneficiation needed for optimum power generation economics.