What is eRoaming?
Patchwork charging infrastructure
Charging infrastructure for electric cars is offered in Germany, and internationally, by many different providers with different contract systems and pricing. Theoretically, drivers can only use charging stations of those operators with whom they have concluded a contract – in order to be able to charge everywhere, drivers would therefore have to enter into a contract with every single operator. This makes no sense for either operators or drivers. Operators solve this problem by providing access to the charging station via eRoaming. This way, drivers only have to sign one contract, but they can use charging stations from different operators. But what exactly happens with eRoaming?
EMPs, CPOs and eRoaming platforms
In order to use this convenient method, drivers sign a contract with an eMobility service provider (EMP or eMSP). The EMP is the contact person for the drivers, issues RFID charging cards and takes care of the pricing structure for the drivers as well as the billing of charging processes. eRoaming platforms usually do not run a charging infrastructure themselves, but facilitate agreements between EMPs and operators (charge point operators = CPOs). The CPOs voluntarily connect to one or more of the EMPs via a roaming platform. Examples of well-known EMPs are EnBW, NewMotion or ADAC.
Drivers have access to the charging stations of all CPOs with which their EMP has concluded a contract via an eRoaming platform. This creates far-reaching charging networks for drivers.
Drivers can see whether charging stations are eRoaming capable by looking at the sticker on the eRoaming platform. The most common eRoaming provider is Hubject with its platform intercharge and a network of over 200,000 charging points worldwide (as of April 2020).
Advantages of eRoaming
Drivers can move freely via eRoaming and charge without hesitation at charging stations of different CPOs. Charging station operators, in turn, can attract more users and generate additional revenue by joining an eRoaming network, thus increasing the utilisation rate and profitability of their charging station.
eRoaming – often a condition for government subsidies
Through eRoaming, charging stations can be made available to the public. Public access via eRoaming is often a prerequisite for applying for state subsidies for the construction of charging stations – because public funds are only approved if no electric car drivers are excluded.
What is the technical background?
To enable roaming, EMPs and CPOs exchange detailed information on charging stations, such as GPS coordinates and authorisation information, as well as CDRs (charge detail records) via the eRoaming platform. Drivers use a mobile app to see eRoaming charging stations’ locations on a map, what the stations’ opening hours are and whether they are currently occupied.
If a driver tries to charge at an eRoaming station, the charging station checks whether it recognises the driver or the RFID charging card used. If not, it forwards the request to the eRoaming platform. The platform checks whether the driver is registered with one of the EMPs. If so, the charging process is started and then billed via the eRoaming platform. In this way, eRoaming enables eCar drivers to charge and pay independently of providers.
