Based on the target annual mobility demand (10 9 km/year), the requirements in terms of PV area were determined. The surface for electricity harvesting was considered by matching the day-by-day demand (considered as constant) with the total supply, including the efficiency losses due to the production of the energy storage molecules and to their reforming to H2 or combustion to produce electricity. Hence, the quantity of energy required is different according The differing efficiency between FCEV and BEV is reflected in the results as the amount of energy for the H2 cases is significantly higher. Additionally, as in the H2 cases all the electricity must be converted into H2 as a first step, the productivity is influenced by the efficiency of the electrolyser (which is ca. 70 % HHV-based). The results show a clear seasonal trend, with an excess of production in summer and the requirement of energy from storage in winter. In the March-September period, the demand needs to be covered by reforming/electrification only sporadically, hinting that these holes could be covered by some intermediate between-days storage, not considered here . On the other hand, during the cold season, there are clusters of days when the synthesis reactor would be active (mainly periods of persistent atmospheric high pressure), showing that the storage unit cannot be deactivated during long time, due to the risk of curtailing a significant amount of electricity .