ISO 15118 protocol

Recommendation by AFIREV following an analysis of the utilities and costs of ISO 15118 communication protocol between electric vehicle and charging point

The ISO 15118 standard considerably empowers the communication between an electric vehicle and a charging station, which is currently limited to analogue control for electrical safety (IEC 61851). It completes the IT architecture of charging ecosystem for electric vehicles, making EV charging simpler, safer and bringing new services to drivers:

– Plug and Charge, which enables the user’s service contract to be automatically identified by simply connecting the charging cable between the vehicle and the charging station, with a high level of IT security and a simplified user experience;

– Smart Charging Management (smart charging), which allows the programming of a charging schedule, negotiated between the station and the vehicle and optimized according to their technical constraints, the needs and requirements of the driver and the electrical constraints of the network;

– Bidirectionality of charging[1], which makes it possible to negotiate and optimize, via the station, the reinjection of electricity stored in the vehicle into the home (vehicle-to-home), the building (vehicle-to-building) or the grid (vehicle-to-grid);

– Other services can be designed and provided to drivers, for example for charging without cable handling (inductive or automated charging).

The ISO 15118 standard also ensures better prevention of cybercrime (energy theft, identity theft, cyber vandalism, etc.) and protection of drivers’ data, on which AFIREV has published a recommendation. Subsequently, in 2022, a cooperation of several European partners in line with this recommendation developed a working demonstrator of a PKI key certificate architecture not relying on a single monopoly player, presented in this video.

DC charging stations equipped with CCS chargers already incorporate a reduced version of this standard. Vehicles with the first full version of the standard (published in 2014) are starting to be marketed and AC charging stations compatible with this version will be available in 2020. This standard should thus be gradually deployed in the coming years on a European scale and involve all actors at play in EV charging ecosystem: infrastructure developers and owners, charging station manufacturers, operators of charging infrastructures, mobility service operators, roaming platforms, car manufacturers and, ultimately, energy providers.

However, the deployment of ISO 15118 and associated services generates costs to be considered against its benefits: hardware purchase, engineering, development, software maintenance and telecommunication costs. In order to enlighten the actors, AFIREV has made an assessment of these costs through interviews with actors and experts involved in the development of the standard. The results of this analysis lead to the estimation of deployment costs[2]according to a volume of charging points[3], which is related either to the amortization annuity of the recharging points, or to the transaction, as follows:

– An additional cost between 5 and 7 €/year and per charging point;

– An additional cost between 5 and 10 euro cents per charging session (allocating the above-mentioned additional cost to each charging session and adding cost of mobility contract management).

This estimate can be considered as a ceiling, as the actual foreseeable costs are expected to decrease with the development of the technology.

Consequently, and considering: the effective usefulness of the new functions brought by 15118, the reasonable implementation cost compared to the amortization annuity and charging session costs, and the European industrial stake, AFIREV commits the essential actors concerned, beyond AFIREV members, to work on this deployment in France at the beginning of 2020 with the mobilization of adequate resources.

More details and practical recommendations on this purpose are made in the published report (in french). In order to carry out this project, a concerted effort to accompany the actors by means of expertise, training, tool development, support and certification structures will have to be carried out with the appropriate means in 2020 and 2021.

AFIREV proposes the following main action areas:

  1. Specification of the different use cases of ISO 15118 standard and the associated services, with the objective of recommending implementation profiles of the standard adapted to each use case;
  2. Implementation of a concerted PKI key architecture at European level, in accordance with the proposals of the AFIREV in the report on this subject;
  3. Realization of workshop-schools for implementation, experimentation and demonstrators of use cases in complete systems (at least with a car manufacturer, a charging point operator and a mobility service provider) to learn how to operate 15118 in an interoperable way and to define the support tools necessary for its deployment (supporting expertise structures, software brick libraries, training tools, certification bodies, etc.);
  4. Development of a deployment strategy: priorities and deadlines for infrastructures investors of various kinds (public, private), definition of generations and versions of charging stations and systems, etc.);
  5. Drafting of a deployment reference framework (timetable, recommendations, guides) specifically for investors in publicly accessible infrastructures and private sectors (businesses, collective residential, car-sharing) with recommendation for specifications for the purchase of charging stations and subcontracting of their supervision.

The following up on this matter is the object of MOBENA project. See also the video of demonstration of an interoperable PKI architecture for ISO 15118.

[1] Compatible only with a second version of the standard (15118-20)

[2] Costs for a network of charging stations pool open to the public, investments being shared at European scale, without taking into account costs on the EV side, nor the two-way charging service (all the assumptions are detailed in part 2.2 of the report).

[3] 20,000 ISO 15118 compatible charging points open to the public by 2025, more than 300,000 by 2035.