The implementation of ADEX technology to the control of combustion in Group II in the coal fired power plant at Andorra (Teruel) has achieved extraordinary results. The continuous changes of power generated in coal fired power plant brought about by variable demand for electricity, together with the complexity inherent in the coal combustion process itself, makes boiler pressure and generated power the two most critical control loops in a coal fired power plant. An ADEX optimised, adaptive control system applied to the combustion process in the ENDESA power plant has succeeded in optimising the stability and performance of the process in terms of pressure and generated power, totally automating its function under both constant and variable load. In the latter case, the ADEX system has easily handled ramps in power change of 5MW/min in response to unexpected changes in demand. These ramps almost double the incline of the changes which were considered viable in the previous control system based on PID methodology and which employed advanced strategies designed on the basis of the experience and professionalism of the people in the plant responsible for control and instrumentation. In addition, the optimisation resulted in a drastic reduction in CO and NOx emissions.