In coal power plants from Romania, there is a major interest for the implementation of digital systems for monitoring and control, replacing the conventional control systems for power, frequency and voltage. Therefore it is necessary to develop mathematical models capable to accurately describe both dynamic and stationary behaviour of the coal burning units, in order to be able to implement digital control algorithms. Moreover, it is necessary to implement systems for monitoring and control of coal power plants, in order to optimise the use of the fuel resources. This paper presents the possibilities of modelling and simulation of the heat exchange in power plants and performs an analysis of different control structures and algorithms.