Intro to EV


This page is for partners who are new to the EV world.

Below we briefly describe key concepts, relationships and further links.


Key players:

  • Driver of an EV
  • CPO who owns and manages an EVSE
  • eMSP holds the relationship with the Driver and provides e.g. RFID card
  • Roaming Hubs that act as clearing houses between CPOs and eMSPs

Note: CPOs can also have eMSPs businesses. Additionally some build their own hardware. Equally there are pure players in each category.

Key activities

Basic scenario;
Driver connects their EV car to a charge station (EVSE). The CPO checks whether this card is authorized to charge on this charge station. If it is, the system will start the charging session.

Following a successful charging session, the CPO will send a CDR to the eMSP where the driver is registered with. The eMSP collects payment from the Driver and pays the CPO the difference.

Closed network

The basic scenario is where a company is both CPO and eMSP. This company (lets call them Company A) sets up charge stations and provides charge cards to customers to charge on this network. Drivers need to have RFID charge cards to be able to charge on Company A's charge stations.


In order for customers of another Company B to also charge on Company's As network, there are two options:

  1. 'Driver registers with Company A - Driver needs to have charge cards for every charging network.
  2. Roaming - enable Drivers of company A and B to charge on each other's network.

To enable roaming, both companies need to have agreement with each other (technically the CPO with the eMSP of each side).

This can either go through a Roaming Hubs or via a direct connection.

Open network with payment terminals

Use of RFID cards and readers is widespread on continental Europe. In the UK and the USA, the use of ad-hoc payments at the charge station are more common. Therefore eMSPs and roaming have a different role and importance.

Key protocols & standards

  • OCPP standardizes communication between the EVSE and CPO
  • ISO 15188 is a relatively new standard to manage Plug & Charge / Autocharge
  • OCPI : One of two main European standards for communication between CPOs, eMSPs and Roaming Hubs. See also OCPI
  • OICP: One of two main European standards for communication between CPOs, eMSPs and Roaming Hubs.
  • OSCP - Open Smart Charging Protocol - standardizes connection between Distribution System Operators and CPOs and eMSP. Future looking use cases towards managing grid capacity.