The Roaming Protocol

Understanding OCPI: The Open Charge Point Interface

OCPI is a free, independent, open-source protocol that facilitates automated roaming between Charge Point Operators (CPOs) and eMobility Service Providers (eMSPs). It's the key to creating a seamless, accessible, and user-friendly charging network for all EV drivers, regardless of which service they subscribe to.

Why OCPI is Essential for EV Roaming

While OCPP manages communication between a charger and its management system, OCPI handles the communication *between different charging networks*. This allows a driver from one network to seamlessly use a charger from another.

Seamless Driver Experience: Drivers can use one app or RFID card to access thousands of chargers across different networks, eliminating "range anxiety."
Automated Billing & Reconciliation: OCPI automates the exchange of billing information (CDRs) between partners, simplifying complex financial settlements.
Real-Time Data Exchange: Provides live information on station location, availability, and pricing, ensuring drivers always have accurate data.

An electric car charging with network symbols connecting it to the world

A group of diverse professionals working together on a project

Governed by the EVRoaming Foundation

The OCPI protocol is managed and developed by the **EVRoaming Foundation**, a non-profit organization based in the Netherlands. Its mission is to ensure OCPI remains a free, independent, and robust standard for the global e-mobility community.

Initiated in 2014 by market players in the Netherlands and Germany, OCPI was created to solve the practical challenges of cross-network charging. It was designed to be a simple, scalable, and independent alternative to more complex, proprietary systems. The foundation now includes hundreds of members from around the world, all collaborating to drive the future of accessible EV roaming.

Core OCPI Modules

OCPI is structured into different modules, each handling a specific type of information to ensure smooth and reliable roaming.

Locations

Shares detailed information about charging station locations, including address, connector types, and real-time availability status.

Tokens

Allows for the validation of driver identification (like RFID cards or app IDs) across different networks to authorize charging.

Tariffs & CDRs

Exchanges pricing information (Tariffs) and sends detailed session records (CDRs) after charging for accurate billing between partners.

Sessions

Provides real-time information about an ongoing charging session, including energy consumed and duration.

Commands

Enables one network to send remote commands, such as start or stop charging, to a station on a partner network.