The ISO 15118-20 standard is designed to enable bidirectional charging for EVs. However, it must be specified for topics such as “Distributed Energy Resources” (or “DER”) requirements and for compliance testing. Today, each car or charging station manufacturer develops specific solutions, which means that EVs and charging stations cannot be combined at will. The biggest obstacle to the widespread adoption of V2G today is the non-interoperable protocol and non-standardized grid codes. As a result, economies of scale cannot be achieved, there is a lack of real market competition, there is no price erosion for bidirectional charging stations and the widespread introduction of V2X is delayed. HEV-TCP is addressing the interoperability issues with the new task 53 “Interoperability of bidirectional Charging”. It has two main objectives: interoperability between bidirectional charging stations and vehicles, and between charging stations and distribution networks.