Interventions on thermal plants, shown in Fig. 12, have mostly payback times lower than the average life of a plant and are advantageous even without access to the deductions provided by Italian laws [13]. The high favorability economic combined with the simplicity of these interventions, which can be performed without additional costs and with no differentiation between historical and modern buildings, give these works a priority. In this case it is important to consider that the favorability of the intervention may be even greater when one considers that the divergence between real consumption and theoretical consumption can be attributed mainly to the low efficiency of the regulation systems.