What is the difference between OCPP and OCPI?

The electric vehicle (EV) industry has witnessed rapid growth over the past few years, with more and more EV charging stations being installed worldwide. To enable interoperability and seamless communication between various charging stations, standardized protocols like Open Charge Point Protocol (OCPP) and Open Charge Point Interface (OCPI) have been developed. In this article, we will explore the differences between OCPP and OCPI, shedding light on their specifications and use cases.

OCPP: The Backbone of Charging Station Communication

OCPP, which stands for Open Charge Point Protocol, is an open-source application layer protocol that facilitates smooth and secure communication between charging stations and central management systems (CMS). It provides a standardized way for charging stations to exchange information and perform various functions.

One of the key features of OCPP is its flexibility. It supports multiple transport layers, including TCP/IP, WebSocket, and SOAP, making it compatible with various communication mediums. This allows charging station manufacturers to choose the appropriate transport layer based on their specific requirements and infrastructure.

OCPP also defines a set of common messages and actions that charging stations and CMS can execute. For example, it enables the start and stop of charging sessions, monitoring of charging status, retrieval of historical data, and firmware updates. By adhering to the OCPP standard, different charging station models from different manufacturers can seamlessly communicate, ensuring interoperability and ease of integration.

OCPI: Enabling Roaming and Interconnections

While OCPP focuses on the communication between charging stations and central management systems, Open Charge Point Interface (OCPI) aims to establish a standardized method for EV charging networks to interact with each other. OCPI addresses the need for roaming and interconnections between different charging networks, enabling EV drivers to charge their vehicles at various charging stations without any compatibility issues.

The main purpose of OCPI is to provide a common language and set of protocols for different charging networks to share essential information. This includes details about available charging stations, pricing, reservations, and real-time status updates. With OCPI, EV drivers can locate and navigate to nearby charging stations, check the availability of charging ports, and make payments efficiently, regardless of the charging network they are registered with.

Similar to OCPP, OCPI is designed with flexibility in mind. It supports different authentication methods, like OAut or JSON Web Tokens, ensuring secure and reliable communication between charging networks. Additionally, OCPI accommodates different data formats, such as JSON or XML, making it adaptable to the existing infrastructure of charging networks.

Conclusion

In summary, OCPP and OCPI play crucial roles in the development of the EV charging ecosystem. OCPP defines the standard communication protocol between charging stations and central management systems, ensuring interoperability and smooth operation. On the other hand, OCPI focuses on enabling roaming and interconnections between different charging networks, creating a seamless experience for EV drivers.

Both OCPP and OCPI contribute to the growth and widespread adoption of EVs by providing a standardized framework for communication and integration. As the EV industry continues to expand, these protocols will continue to evolve, addressing new challenges and enabling further advancements in charging infrastructure.