Gas turbine power plants have characteristics that make them well-suited for applications where fast dynamics and high outputs are required, for example to accommodate variable load profiles and intermittent energy sources. However, this flexibility comes at a cost: these plants are much more expensive to operate than other types of power plants. This article proposes a new energy management system that enables a flexible and efficient operation of gas power plants. It is based on a multi-agent system combined with an economic and environmental dispatch algorithm obtained through an optimization algorithm based on differential evolution. Simulation results for a test system based on actual data of a GE 9E turbine show that the system helps reducing operation costs by up 4.7% and NOx emissions by up to 20.5%, and can be used with a large variety of gas power plants, as well as be adapted to evolutions in the plant structure. (C) 2012 Elsevier Ltd. All rights reserved.