Introduction
Tariffs are used to provide a price for sessions and charge detail records. The table below show which information can be configured on a tariff.
| Field | Description | Roaming |
|---|---|---|
| Ocpi identifier | This code is used when the tariff is shared with roaming partners via the OCPI protocol. See the OCPI paragraph for more information. | ✓ |
| Hubject identifier | Identifier that is used when creating a so called "service offer" on the Hubject roaming platform. See the Hubject paragraph for more information. | ✓ |
| Start tariff | The price when a session is started. | |
| Price per Kwh | Price per Kwh for the session. Prices are rounded per wh. | |
| Currency | The currency for the session. | |
| VAT | The VAT that is applicable for the sessions. | |
| Charging Time | Price per minute as long as energy is being transmitted. | |
| Parking Time | Price per minute when the EV is still connected, the session is not completed yet but no energy is being transmitted anymore. |
Hubject
| Attention: It's mandatory to have a tariff available on a charging session for Hubject. If there is no tariff selected on a charger, a default value of AC1, AC3 and DC will be used. These values are selected based on the power of the EVSE in the Location overview screen. |
When tariffs are used for a Hubject roaming session, the tariff codes need to match the "name" of the authorization service offer in the Hubject portal. To simplify this process, it is possible to change the Hubject identifier of a tariff. Pay attention that only one unique Hubject identifier can be active.
OCPI
For roaming communcation via OCPI (like e-clearing, Gireve or P2P connections with EMPs), we support the tariffs module. This means that tariffs are exchanged with the OCPI roaming partners. The EMP will exactly know what the CPO price will be for a certain EVSE.
Active tariff
When a session is started, the applicable tariff is determined based on the start datetime of the session. The tariff that is active at that specific time will be used during the complete session. The tariff can be changed during a session but it will not be applied onto the running sessions.
Calculation
The following calculation is made to determine the total amount of the session and the cdr. Important to know is that the MeterStart and MeterStop are being transmitted in Wh.
| Total = Tariff.StartTariff + ((StartTransaction.MeterStop - StopTransaction.MeterStart) * (Tariff.PricePerKwh / 1000)) When charging time and/or parking time tariff is configured: Total ChargingTime = RoundUp((Duration - GracePeriod) / StepSize) * Tariff. |
Time-based tariffs
When a time-based tariff is configured, it will be added to the startariff and the energy tariff. This enables to use Parking Time to discourage EV drivers to keep their car on the parking spot while not charging. Make sure that these price components are clear for the EV drivers to avoid confusion. Alle tariff components including the time-based tariffs are also shared via OCPI. The session screen also shows in detail how the total price is being calculated.
Grace period
Setting up time-based tariffs allows for configuring a grace period. This enables a certain leniency that can be applied. This will give the EV driver some time to remove the car before the driver gets charged for this.
Smart Charging (AC/DC)
We advice to use time-based charging only on DC chargers. Smart charging on an AC charger can suspend a charging session and then time-based charging is not fair to the EV driver. Parking time will also be reset to 0 when at the end of a charging session a short amount of energy is being transmitted.