Use a Time-based Tariff to Discourage Blocking of Electric Vehicle Chargers, Study Recommends.

Analysis of the data yield several insights about real-world use of charging infrastructure. These insights include:

• Fully charged vehicles frequently block public charging infrastructure. During an observation period, the average blocked time (time that an EV was connected while already fully charged) for a charging station was 595 hours, almost as much as the charging time of 651 hours.
• Faster charging systems (e.g., high power DC fast charging) can discourage blocking of chargers
• Carsharing vehicles block chargers at much higher rates than privately owned vehicles

To improve turnover at charging stations, operators should consider using a time-based tariff system as opposed to a session fee. The average blocking rate (proportion of time at the charger while already fully charged) under a time-based system was 0.12 vs. 0.2 when a session-based fee was used.