Title: Why Electric Vehicle Charging Stations on Highways are Overwhelmed

Highway travelers with low battery levels, in need of a recharge and on a tight schedule, often face frustration when arriving at charging stations only to find them occupied. This scenario not only causes inconvenience but also highlights a mismatch between drivers' real needs and the functioning of these stations.

Title: Why Electric Vehicle Charging Stations on Highways are Overwhelmed

The issue concentrates on routes where recharging is essential. On highways, a charging station serves a different purpose than in urban areas or at home. Electric vehicles typically arrive after several hours of driving, with depleted batteries and limited realistic alternatives nearby. The driver does not recharge for comfort; they recharge to complete their journey. This constraint creates a strong concentration of demand at certain locations.

Certain highways, such as those leading to the Mediterranean, the Alps, the Atlantic coast, or borders, are particularly affected. The phenomenon is also linked to travel habits. Many people stop at the same times: before lunch, between 12 pm and 2 pm, in the late afternoon, or early evening. They prefer well-known rest stops offering toilets, restaurants, fuel stations, and rapid charging. However, a station may seem well-equipped yet become insufficient during a short period.

Eight, twelve, or sixteen charging points usually suffice for ordinary traffic. But during a surge, multiple simultaneous arrivals can form a queue. This bottleneck does not solely depend on the number of electric vehicles on the roads. It primarily depends on the time, the route taken, and the time spent at each charging station.

Saturation comes from a funnel effect, amplified by rapid charging. The highway charging station is often overwhelmed because all vehicles need energy at the same locations and nearly at the same time. On a long journey, drivers do not choose each stop freely. Their autonomy, weather, speed, terrain, and charge level direct them to compatible stations along their route. An area then becomes a mandatory stop.

If the next charging site is distant, out of order, less powerful, or situated after an impractical exit, drivers prefer to wait. They avoid the risk of running low on reserve. The charging speed also explains part of the problem. A very powerful charging station can deliver a lot of energy, but it does not make all vehicles rapid chargers equally. The actual power accepted depends on the vehicle, its battery temperature, charge level, and pre-conditioning system. Moreover, charging slows down progressively. A battery typically passes more quickly from a low charge level to around 60% before the pace slows dramatically.