The aim of this work is the development of an optimization tool that could be a useful instrument in the evaluation of the designing, sizing and managing of the cogenerative plants. This tool is a software called ECoMP, the acronym for Economic Cogeneration Modular Program. In this name the two main characteristics of the software are integrated: the modular structure and the purpose, that is the economical optimization of the cogenerative plants. In order to include innovative plant modules in the code, the fuel cell hybrid plants have been analyzed both from a static and dynamic point of view. The hybrid plant analyzed is composed by a Molten Carbonate Fuel Cell (MCFC) coupled with a micro gas turbine. The basics of any module are the off design performances of a plant and to do this, it has been necessary to study in depth the behaviour of the fuel cell hybrid systems. To develop a new ECoMP module it is necessary to include in the software the off design performance curves and to obtain these curves, a new model has needed. The structure of ECoMP is time depending and it is necessary to know the dynamic behaviour of the hybrid plants and his time response to a load variation, to a startup or a shutdown operation, to include them in ECoMP. With this purpose, a transient model has been developed.
