Recupero di energia dai rifiuti: dall'economia del danno all'economia del benessere - The organization of an economical system is based on a flux of energy and materials that receive from the external environment. In nature evolution move systems to a growing efficiency in circulating energy and materials to let them producing positive effects implementing the internal organization, to create new opportunities to move far from equilibrium, to create differences. But while natural systems operate cyclic processes, economical systems are linear, and using concentrated resources as input and producing wastes that spread in the environment in a way that make them no more reusable, as much it success in growth as much it approximate its end. From an energy life cycle analysis of a material used in an economical process we can see that is much more efficient reuse goods and recycle materials than incinerate them. For instance we study the case of a PET bottle to deduce that reusing 20 times a 50g PET bottle can save 5 times more energy than electricity produced by burning 20 one-use 25g bottles in an incinerator.