How Does an eRoaming Charging Station Work?

Germany’s charging infrastructure is a patchwork. To drive forward electric mobility and make it easier for EV users, a solution was urgently needed: eRoaming. This technology enables drivers to access public charging stations operated by different Charge Point Operators (CPOs) using an RFID charging card.

Find out how eRoaming charging stations work and why they are becoming a key technology for the future of electric mobility.

EV Charging Infrastructure Made Simple

In Germany – and internationally – electric vehicle charging infrastructure is provided by numerous operators, each with their own contract systems and tariffs. In theory, drivers can only use charging stations operated by providers with whom they have a contract. To charge everywhere, they would need to sign a contract with each individual operator. This is neither practical for operators nor convenient for drivers.

The solution? eRoaming.

Through eRoaming, charging stations are made accessible across different networks. With just one eRoaming charging card, EV drivers can access a wide range of public charging stations. This means they only need a single contract while still being able to use charging stations from various operators.

But what exactly is behind eRoaming?

EMP, CPO, and eRoaming Platforms – What Do They Mean?

For eRoaming charging infrastructure to function smoothly, seamless collaboration between operators is essential.

Electromobility Service Provider (EMP)

To benefit from eRoaming, EV drivers sign a contract with an Electromobility Service Provider (EMP or eMSP). Well-known EMPs include EnBW, NewMotion, and ADAC.

The EMP serves as the main point of contact for drivers, issuing RFID charging cards for EVs and managing tariff structures and billing for charging sessions. (RFID = Radio Frequency Identification)

Charge Point Operators (CPOs)

eRoaming platforms typically do not operate their own charging infrastructure. Instead, they facilitate agreements between EMPs and Charge Point Operators (CPOs). CPOs voluntarily connect to one or more EMPs via a roaming platform.

Drivers can access charging stations operated by any CPO that has a roaming agreement with their EMP. This creates extensive charging networks for EV users.

eRoaming Platforms

Drivers can identify whether a charging station supports eRoaming by looking for the sticker of the eRoaming platform. The most widely used eRoaming provider is Hubject, which operates the intercharge platform. As of 2023, Hubject enables access to over 400,000 charging points worldwide through its network of over 960 charging service providers.

Benefits of eRoaming

Thanks to eRoaming, EV drivers can move freely and charge their vehicle at public charging stations operated by different CPOs without any restrictions. For charging station operators, joining an eRoaming network helps attract more users and generate additional revenue, ultimately increasing both utilisation and profitability.

eRoaming – Often a Requirement for Government Subsidies

In many cases, receiving government subsidies for setting up charging stations requires public access via eRoaming. This regulation ensures that no EV drivers are excluded, which is a key condition for the allocation of public funding.

How Does eRoaming Work?

To enable roaming, Electromobility Service Providers (EMPs) and Charge Point Operators (CPOs) exchange detailed information about charging stations via an eRoaming platform. This includes GPS coordinates, authorisation details, and Charge Detail Records (CDRs).

EV drivers can use a mobile app to locate eRoaming-compatible charging stations, check their availability, and view their opening hours.

When a driver initiates a charging session at an eRoaming station, the charging point verifies whether the driver or the RFID charging card is recognised. If not, the request is forwarded to the eRoaming platform, which checks whether the driver is registered with one of the EMPs. If so, the charging process begins, and billing is handled via the eRoaming platform.

This enables EV drivers to charge and pay independently of the charging station operator, ensuring a seamless and convenient charging experience.

Step-by-Step Guide: How to Use an eRoaming Charging Station

1. Sign a Contract: Choose an Electromobility Service Provider (EMP) that supports eRoaming and sign a contract. Popular EMPs in Europe include EnBW, NewMotion, and ADAC.

2. Receive an RFID Charging Card: Once your contract is in place, your EMP will provide you with an RFID charging card. This card is required to start charging sessions at eRoaming-compatible charging stations.

3. Download the App: Download your EMP’s mobile app. The app allows you to locate available charging stations, check the status of charging points, and monitor your charging sessions.

4. Find a Charging Station: Use the app to locate a nearby eRoaming-compatible charging station. The app will also indicate whether the station is available or currently in use.

5. Drive to the Charging Station: Navigate to the selected charging point and ensure that it is compatible with your EMP’s eRoaming network.

6. Authenticate Yourself: Hold your RFID charging card to the station’s reader to authenticate yourself. In some cases, authentication can also be completed via the EMP’s app.

7. Start the Charging Session: Follow the instructions on the charging station or in the app to begin charging. Plug the charging cable into your vehicle and the charging station.

8. Monitor the Charging Process: Check the progress of your charging session via the station’s display or your EMP’s app. Some apps also send notifications when charging is complete.

9. End the Charging Session: Follow the instructions to safely end the charging session. This may include unplugging the charging cable and re-authenticating to finalise the session.

10. Payment & Billing: The charging session is automatically billed via your EMP. The cost is calculated based on your contract and tariff.