Thermo-environmental evaluation of traditional cogenerative and fuel cell plants

A model is proposed that can contemporaneously determine the optimum techno-economic working trajectory of any cogenerative plant and achieve the successive thermodynamic and environmental comparison. By means of the introduction of suitable coefficients, based on aspects of an energy and environmental nature, an engineering approach to the concept of sustainable development is provided. Moreover, the model enables the recording, for every technological solution, in optimum running and planning conditions, of the working moments and the load diagrams of the primary engine and of the possible auxiliary boiler. From a study of the results obtained from the application of the proposed procedure to a real case, using plant solutions with differing degrees of technological maturity, it emerged that the analysis of economic convenience, despite often being a decisive factor in the choice of a cogenerative system, does not necessarily provide a complete evaluation of the said system.