The methodology used seeks firstly to determine the energy savings achieved after the energy renovation in the 7.1 million priority dwellings, in order to study their economic impact. In that sense, the 16 million dwellings in the area are classified into 2,100 cases with similar characteristics; the energy simulation is carried out on these groups thanks to the engine of the urbanZEB tool, which makes it possible to define the energy savings achieved in each case and extrapolate them to the dwellings as a whole. Prioritisation is established on the basis of a probability by efficiency matrix, which defines a package of 7.1 million dwellings with high probability and high efficiency of intervention, of which 1.2 million will be renovated in the period 2021-2030 and another 5.9 million in the period 2031-2050. Finally, a microeconomic cost-benefit analysis is carried out considering various financing scenarios over 15, 20, 25 and 30 years.