The innovative energy systems operating in Ferrara were designed with the aim of saving energy and reduce the emissions towards the environment. A suitable integration of the energy sources and the arrangement of the plants in two separate islands allowed to obtain an efficient and interesting overall system, supplying both heat and electricity to the users of the town. Geothermal energy, wastes burning, cogeneration, energy recovery and integrative boilers have properly been matched. A previous analysis and simulation of the plants working allowed the authors to choose the size of each sub-system and to foresee the operation results throughout the year. These results are very close to the experimental data coming from actual operation modes. The overall system is very interesting and brings about a remarkable saving of both energy and environmental impact