What is ISO 15118 in EV charging?

ISO 15118 is a family of standards for communication between an electric vehicle and charging equipment. It supports functions such as Plug and Charge, while Part 20 defines messages for bidirectional power transfer [S1], [S2], [S3]. Ask which part, features and vehicle combinations your proposed system supports before treating it as an export-capable installation. Checked October 2026.

Last checked 19 October 2026

What is ISO 15118?

ISO 15118 is a family of standards describing digital communication between an electric vehicle and charging equipment [S1].

Why it matters for your site: a proposal should identify the supported part and enabled functions, alongside the vehicles and service arrangements that make them usable.

ISO 15118-20 defines communication messages and sequences for bidirectional power transfer [S2]. That means the standard covers instructions for energy moving in either direction; it does not certify your installation for export.

How does it relate to Plug and Charge and smart charging?

Plug and Charge uses ISO 15118 interfaces to automate identification and billing, removing the separate card or app identification step for a compatible session [S3]. Ask who manages the charging contract and security certificates, and how a driver starts charging if automatic identification fails.

Smart charging uses communication to coordinate charging requirements. The Open Charge Alliance identifies ISO 15118 support and additional smart charging functions in OCPP 2.0.1 [S4]. Keep the interfaces distinct: OCPP connects your charger to management software, while ISO 15118 concerns communication with the vehicle.

Ask the installer to demonstrate schedule changes with the intended vehicles. A protocol label does not establish that the proposed service is configured or supported.

Does ISO 15118 mean your site can use vehicle-to-grid?

Part 20 expressly includes bidirectional communication [S2]. Ask for a complete compatibility statement covering vehicle, charger, controls and connection permissions. State whether you want normal charging, building supply or grid export.

Use the vehicle-to-grid guide for that wider project assessment. Keep electricity-price assumptions separate using the charging cost tool.

Next step

Browse the glossary for related definitions.

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