Developing roaming protocols for EV charging: Insights from the field

As electric vehicles (EVs) become more mainstream, roaming will become an increasingly important topic; more and more EV drivers want to connect to available charging networks. Roaming is enabled via communication protocols, which also allow for services such as information on availability and tariffs of charge points. Currently, there are several roaming protocols in use within Europe. With multiple roaming protocols gateway technologies are necessary to achieve full interoperability of charge points, which has disadvantages such as extra costs and limited functionality. Whether multiple protocols will be continued to used or one protocol becomes dominant in the future does not only depend on technical performance of the protocols, but also on attitudes of stakeholders towards them. To investigate these attitudes, we have interviewed roaming experts across Europe. Our results address current issues in roaming and point to trade-offs in how to proceed in achieving full interoperability for charging infrastructure.