Open Protocols for EV Charging

The task of charging Electric Vehicles is becoming and increasingly sophisticated business as the EVs, the chargepoints and the assorted back offices need more and more data to drive payments, load control, roaming and indeed charging itself. In this article, we will outline some of the main data protocols associated with EV charging. We will enter into greater detail on some of these in later posts.

ISO 15118:

ISO 15118 is an international standard defining the communication protocols between an EV and an electric vehicle charging station.

The standard incorporates the Plug & Charge feature that is used by some electric vehicle networks. Plug and Charge enables an EV to automatically identify and  authorise itself to a charging station  on behalf of the driver, to receive energy for recharging its battery.  The only action required by the driver is to plug the charging cable  into the EV and/or charging station. The standard can be used for both  wired (AC and DC charging) and wireless charging for electric vehicles. This process is enabled by a digital certificate located in the vehicle, allowing it to communicate with the charging point management system (CPMS). This enables a seamless end-to-end charging process, which includes automatic authentication and billing, and avoids the need to use an RFID card, an app or to memorise PIN numbers.

ISO 15118 also enables bi-directional EV charging, otherwise known as vehicle-to-grid (V2G). With V2G, electric vehicles will be able to feed energy back to the grid when needed, thus helping reduce costly system peaks and ensuring a more intelligent, reliable grid.

OCPP – Open Charge Point Protocol

The Open Charge Point Protocol (OCPP) is an application protocol for communication between electric vehicle charging stations and a central management system. The protocol was developed by the Open Charge Alliance (OCA) for the EV infrastructure market, and is considered the de-facto standard for charging infrastructure interoperability among charging equipment manufacturers, software and systems providers, charging network operators and research organisations. The protocol is a proven way to optimise the cost and minimise the risk of networked infrastructure investments. It provides flexibility for infrastructure operators to be EVSE-agnostic and allows easy access for EV drivers.

Many key players in the EV industry (charging station manufacturers, utilities, charge point operators and back-office software providers) contributed to the development of the protocol. Most implementation of OCPP out there are probably based on the 1.6 version of the standard. This is a pretty powerful protocol but it somewhat lacks in the areas of security and smart charging.

The latest version, OCPP 2.0, has a lot of new and improved features for device management, transaction handling, security, smart charging functionalities, support for display and messaging and many additional improvements requested by the EV charging community. It also offers the option to support plug and charge for electric vehicles supporting the ISO 15118 protocol.

OCPI – Open Charge Point Interface:

The Open Charge Point Interface (OCPI) standard managed by the EVRoaming Foundation is designed for exchanging information about charge points between charge point operators and e-mobility service providers to enable scalable and automated EV roaming. The following is supported by the latest version of the standard (V2.2):

  • Roaming via hub
  • Roaming peer-2-peer
  • Roaming with mixed roles
  • Authorization
  • Reservation
  • Provide tariff information
  • Billing
  • Provide static charge point information (e.g. location)
  • Provide real-time charge point status information
  • Provide (real-time) session information
  • Provide CDR information
  • Remote start/stop (for use via mobile app)
  • Smart charging support
  • Platform monitoring

OSCP – Open Smart Charging Protocol

OSCP is an open protocol for communications between a charge point management system and an energy management system of a site owner or a DSO system.

The protocol can be used to communicate a real-time prediction of the local electricity grid capacity to the charge point operator. OSCP facilitates capacity-based smart charging of EVs.

OCPI (Open Charge Point Interface)

OCPI is an open protocol used for connections between charge station operators and service providers. In a nutshell, this protocol facilitates automated roaming for EV drivers across several EV charging networks. The protocol provides accurate charge station data such as location, accessibility, and pricing, and it takes into account real-time billing and mobile access to charge stations. The ultimate goal is to allow any EV driver to charge at any charging station in the EU.

OpenADR – Open Automated Demand Response

OpenADR is an open and secured foundation for interoperable information exchange to facilitate automated demand response.

It is typically used to send information and signals between distribution system operators (DSOs), utilities and energy management and control systems to balance energy demand during peak times.

Contact us