Today, the vehicles that meet the criteria announced in this directive correspond fairly well to what is on the market. Pure electric vehicles, whether they are depot-loaded or in-line, are very often those that are requested by cities. In fact, this is the category in which we find the most manufacturers, including those from Asian countries. The offer is even very oriented towards electric charging at the depot, which seems to be the most installed solution to date. And yet, it is not without constraints… Indeed, in order to obtain sufficient autonomy, it is necessary to carry a significant quantity of batteries, which not only increase the cost of the vehicle, but also the mass, thus reducing the passenger capacity. No need to remind you that the primary vocation of a public transport vehicle is to transport people, not batteries! Another constraint of the slow charge bus is that it takes time to recharge. On average, a bus with a 300 kWh battery needs to be recharged for 6 hours at the depot during the night. This implies that all vehicles are recharged at the same time and that the energy supply must therefore be very substantial at the depot. In addition, there is the problem of space, as the depots must be redesigned to accommodate all the electric vehicles at the same time in the appropriate safety conditions. Also, despite a higher investment cost in the case of a bus in opportunity charging, this version is certainly the most relevant in pure electric, in terms of vehicle operation. The charge is fast and can be done at any time of the day. But the installation remains costly and requires heavy administrative procedures.