The present thesis works on the concept of energy transition, providing analyses aimed to orient energy policies in a portion of the City of Turin. In particular, it focuses on the building sector, recognising its high impact and the potential for renovation. It takes advantage of 2.5D data, which include elevation information in a bi-dimensional representation, but keeps the option of tridimensional representations open. The work aims to provide a theoretical background to the concepts of digital cartography and energy transition before going into the practical application. This is structured along two axes, one about energy renovation and the other concerning photovoltaic potential.