In power plant Emsland the expert system SR::EPOS continuously determines the current performance factors of the important power plant components including the gas turbo sets. It primarily serves the purpose of the online monitoring of the thermodynamic process quality of the entire power plant process or a sub-process of various plant components. This system detects deviations of the process quality from the ideal or reference condition, assesses and visualizes them. In addition, it facilitates the root cause analysis for the possibly deviating process quality.