Coals that are produced in excess of demand have to be deposited in stockpiles. Spontaneous combustion phenomenon can take place in these stockpiles when convenient conditions are available. In this work, some of the parameters that are effective on the temperature of the stockpiles were measured. Additionally, the size of the coal piles formed on an industrial scale and the equipment used to take temperature measurements are given in detail. Finally, a model developed by the utilization of the statistical analysis technique for Tuncbilek coals was introduced. This model offers an estimation of temperature change behaviour for the coals in stockyards to a high level of accuracy. (c) 2005 Elsevier Ltd. All rights reserved.