Billing system for EV charging stations

What a charging billing system does

A billing system records every charging session, assigns it to a user or vehicle, prices it with the stored tariff and generates a record from it. Technically it is part of a Charge Point Management System (CPMS), which also controls and monitors the charge points.

The key distinction is the meter. A meter answers exactly one question: how much energy flowed. It does not answer who charged, at what price the session is billed and how the amount reaches accounting. Three of the four necessary steps lie outside metering, and that is where NeuraCharge comes in.

Four billing models and what matters in each

Which model applies depends on who owns the vehicle and where it is charged. The requirements for recording, documentation and tax treatment differ significantly.

Wallbox with billing system or billing software?

Many wallboxes are marketed as models “with billing system”. Usually this means the station meters energy, stores sessions and assigns them via RFID card. Actual billing, meaning tariffs per user group, records, export to accounting and managing several sites, requires software in the background.

Manufacturer backends usually only work with their own hardware. If a station from another brand is added later, you end up with two separate billing systems. Manufacturer-independent billing software such as the NeuraCharge Portal connects any OCPP-capable charging station, so you stay free in your choice of hardware and still have one billing system for all sites.

What a reliable record must contain

An amount alone is not enough. To keep a charging session traceable, the record needs:

• Date plus start and end time of the session

• Energy charged in kilowatt-hours

• Unique ID of the charge point

• Assigned person, vehicle or cost centre

• Tariff applied and the resulting amount

• Meter readings at start and end, where the meter provides them

What matters is the level of detail: this data must exist per session, not as a monthly total. A total can no longer be split if several vehicles charged in the same household or at the same charge point.

Handover to accounting and payroll

The part most often forgotten during setup, and the one that costs the most time in operation. Three approaches are common:

File export

Monthly statement per person or cost centre as CSV or PDF. Enough for small fleets, but still requires a manual step.

Interface

Handover via API directly into ERP, accounting or payroll. From around twenty billing-relevant charge points, setup usually pays off within a few months.

Cost centre logic

For consumption to be allocated correctly, the assignment has to happen at the charge point, not later in accounting. That requires every user to have an authorisation medium that is assigned to a department in the system.