To maximize the environmental performance of the energy systems, a paradigm change towards the concept of Smart Multi Energy Systems (SMES) is needed. Optimal design and operation of SMES, which efficiently integrate different energy sources, vectors and needs, is intrinsically a multi-objective problem in terms of sustainability. In this study, we develop a decision support methodology based on performance indicators and Pareto multi-objective optimization, considering economic, environmental and energetic objective functions. In Part I of this research, the so-called conventional approach has been applied to an Italian food industrial district case study. SMES design combines RES and CCHP serving a cluster of firms through district energy distribution networks. Results show that SMES concept can really represent a major opportunity to industrial districts either from the sustainability and the competitiveness perspective. Research also suggests that some financial incentives should be studied so that the solution providing the largest energy saving and GHG emission reduction should become economically attractive
