**4. Discussion**

The next step was to analyze the results in terms of potential energy savings. Firstly, the results of the simulation tool were validated. Secondly, the heat absorbed by water in summer can be both subtracted from the cooling loads and considered as renewable energy production. According to the Energy Performance of Buildings Directive (EPDB 2018) recommendations [2], primary energy factors (PEFs) were used to assess the energy performance.
