In this paper, a thermoeconomic approach is applied to a gas turbine based power plant in order to analyze the performance of its control system when variations in the operating condition, due to some internal or external causes, occur. Different control strategies are compared by quantifying, first, their effect on the performance of the components. Then, their economic impact on the management is determined, by also evaluating the impact of the control system on the components lifetime. (C) 2004 Elsevier Ltd. All rights reserved.