Subscribe & get the latest news in your email
blue x

What are OCPP, IEC 63110 & ISO 15118 and How Do They Relate to V2G?


Won Moon Joo

January 12, 2022

Electric vehicles are all about becoming cleaner and greener, right?

In theory, yes.

However, to deploy millions of electric vehicles that need charging through an electric grid that has never seen more than 2-3% penetration, we need to seriously think about the possible scalability problems.

Thankfully, concepts like V2G (Vehicle to Grid) might help.

Electric Vehicle Gird Integration

V2G is a vehicle and electric grid integration that allows the vehicle to feed energy back into the grid from the EV battery. The basic idea is that the car is charged and discharged based on market signals from the grid.

V2G requires data exchange between the individual vehicles, the chargers, and the grid.

An intelligent system is needed for reliable connection to different components and to effectively control how much and when the vehicle is discharging power into the electric grid.

Open industry standards that have global support from leading manufacturers help to integrate the current and future elements seamlessly. Otherwise, any installation will be proprietary and expensive to maintain.

Some examples are OCPP, IEC 63110, and ISO 15118.

While OCPP (OCPP 1.6 and OCPP 2.0) and ISO 15118 have been used to help facilitate the interoperability of EV charging, IEC 63110 is still in development.

In this article, we’ll discuss the overlaps and differences between the three standards.

OCPP, IEC 63110, ISO 15118

What is meant by ISO and IEC?

ISO is actually not an acronym, but a word derived from the Greek word “isos” meaning “equal.”

Also called the International Organization for Standardization (ISO), the worldwide federation promotes the development of standardization worldwide.

While ISO covers standardization in most fields (quality, IT communication, environment, security, and many more), it excludes electrical and electronic engineering standards. These are the responsibilities of the International Electrotechnical Commission (IEC).

The IEC and ISO are both independent, non-governmental, not-for-profit organizations that develop and publish fully consensus-based International Standards. Both organizations aim to reduce technical barriers to trade.

As electric vehicles are using electronic components and require IT communication, you’ll find ISO and IEC standards in most complex EV charging systems.

What are OCPP, IEC 63110, and ISO 15118?

ISO 15118

ISO 15118 provides a Plug & Charge mechanism that includes a user authorization and a security layer. The standard specifies the communication between the vehicle and the EV charger to enable easy usage of the charging station.

More precisely, EV drivers can plug in their vehicle at a public charger without necessarily using a mobile app or credit card. The vehicle “talks” to the charger. Mercedes Benz and other manufacturers have implemented this with their newest models to make charging more convenient.

An equally important fact is that ISO 15118 enables EV and charging stations to transfer energy data between each other. For example, the vehicle informs the charging station how much energy it requires from the grid.

Accurate energy data from the EV allows the central software systems to make better decisions for concepts of load management (also called Smart Charging). In the next section, we’ll discuss how ISO 15118 also helps to feed energy back to the grid.

IEC 63110

As mentioned above, the IEC specifies an electrotechnical component. IEC 63110 is a new international standard being developed to define a protocol for the “management of electric vehicles charging and discharging infrastructures.”. It will standardize the protocols for EV, EVSE, Charging Station Management System, and grid services.

The illustration below shows that the standard mainly describes the communication between charging stations and CMS or CPO. As the information comes from many secondary actors (SA), IEC 63110 becomes very relevant for utilities like distribution system operators (DSOs) or electric mobility service providers (eMSP).

In short, IEC 63110 covers:

  • Management of energy transfer (e.g. charge session), reporting, including information exchanges related to the required energy, grid usage, contractual data, metering data.
  • Asset Management of EV supply equipment, including controlling, monitoring, maintenance, provisioning, firmware updates, and configuration (profiles) of EV supply equipment.
  • Authentication/authorization/payment of charging and discharging sessions, incl. roaming, pricing, and metering information.
  • The provision of other e-mobility services like reservation.

IEC 63110 general architecture (IEC)
Slide 26 from International Electrotechnical Commission

Everyone who has been working in the EV market will remember keywords such as “reservation”, “payment”, and “metering updates” from OCPP. And indeed, IEC 63110 has some overlap to the older protocol OCPP 1.6 and OCPP 2.0.


OCPP is a protocol that handles the communication between charging stations and the Charging Station Management System (CSMS). OCPP is much “older” than IEC 63110. The first versions were developed in 2009.

OCPP is used to connect EV chargers and software backend systems using bilateral communication. The OCPP client (EV charger) and OCPP server exchange general information such as meter values (Wh, W, V, etc.) and start/stop charging events. OCPP also allows you to send charging commands from the OCPP server to the EV charger through OCPP’s smart charging functionality.

Yet, while OCPP is a widely accepted de facto standard (we estimate that around 60-70% of all chargers use OCPP), and has gained a dominant foothold in the industry, it is not an official international standard.

The Open Charge Alliance (OCA), made up of public and private charging infrastructure providers, promotes OCPP as an open-source communication standard for EV charging stations and network software companies.

So why are OCPP, IEC 63110, and ISO 15118 relevant for V2G?

Given the size of a car battery, enormous amounts of energy storage and consumption are being added to the grid.

The addition of existing and developing technologies like solar generation, on-site batteries, and hydrogen generation, adds to the complexity of the system.

For V2G, we see crucial factors that will require standardization:

  • Many different parties will access charging hardware (utilities, CPOs, eMSPs or OEMs)
  • The wrong execution of V2G can delay the possible departure of vehicles
  • Utilities that request the discharging of vehicles can charge penalties if the V2G events are not executed
  • V2G often requires data from multiple sources such as the vehicle, energy management system, and energy markets
  • Charging stations send sensitive data such as utility data and payment information.

These interactions require a lot of flexibility and security. Standards like OCPP, ISO 15118, and IEC 63110 can ensure reliability, security, and inter-compatibility.

Besides, companies and governments want to accelerate the deployment of charging infrastructure by standardizing interfaces and components.

This is exactly what IEC, ISO, and OCPP are trying to do. Their common purpose is to ensure the secure, affordable, and easy installation and use of EV charging components.

ISO 15118 is easier to differentiate from IEC 63110 and OCPP. The ISO standard only sets out standards for the communication between the vehicle and charger. However, IEC 63110 and OCPP are more overlapping.

Some charging stations communicate with proprietary protocols and others with OCPP, and these elements will probably fall under the international standard IEC 63110. Examples might include:

  • Payment communication
  • User authentication
  • Certain grid management functionalities
  • Plus many more.

Both standards ensure interoperability between charging stations on backend software and we believe that OCPP 2.0 will be a foundational input for IEC 63110.

Some experts say that IEC 63110 will be an upgrade to OCPP. Also, it will receive more international acceptance and acceptance by large companies or governments. An international standard will better enforce interoperability.

Although we expect the release of IEC 63110 to help guarantee international interoperability for the transition to widespread EVs, it is not clear if it actually offers benefits compared to alternatives such as OCPP.

It is also unknown when this new EV standard will be ready. Due to slow development processes and many review phases, it can easily take a couple of years before we will actually see any industrial applications of IEC 63110.

One thing is clear, no one wants to slow down the development of EV charging deployments. Instead, we’ll see continuous improvement from one standard to another standard.

Read more about how to implement OCPP to smart charging here

Related Posts
See All Posts

Learn how fleet operators use Ampcontrol

Ampcontrol is a cloud-based software that seamlessly connects to charging networks, vehicles, fleet systems, and other software systems. No hardware needed, just a one-time integration.