The reev EMS enables grid-compatible charging for any EV infrastructure. This fulfils the requirements of Section 14a of the German Energy Industry Act (EnWG), which apply to all charging stations connected to the low-voltage grid from January 1, 2024, with a nominal power greater than 4.2 kW.
To prevent overloading the power grid, the grid operator may temporarily reduce the electricity consumption of charging stations. EV operators may benefit from this by being entitled to reduced grid fees.
If new charging stations are being planned, charge point operators should contact their local grid operator as early as possible and apply for the applicable fee reduction. Existing systems may also be voluntarily registered to receive the reduced grid fees.
Two options are available:
Module 1: A flat-rate discount on the grid fee is granted for each connection point. The discount amount varies by grid operator but typically ranges from €110 to €160 gross per year.
Module 2: A 60% reduction in the grid fee is granted per connection point. This option requires that the charging stations are connected via a dedicated, separate electricity meter.
In addition, installers should confirm with the local grid operator whether and how they intend to implement grid-compatible control. reev GmbH is in no way responsible for this, nor is it entitled to give suggestions.
Technical implementation
The technical method for applying temporary power reductions is not yet standardized. Currently, electricians must determine how to implement grid-compatible control on a case-by-case basis. The reev EMS supports grid control through a ripple control receiver (RCR).
In this setup, a ripple control receiver is installed at the charging site and connected to a Teltonika gateway. The gateway receives switching signals from the grid operator via the relay contact of the RCR and sends them to the reev EMS, which then dynamically adjusts the power of the EV infrastructure in real-time accordingly.
Note: This configuration is intended for compliance with §14a EnWG. However, it may also be used to integrate building management systems or fire alarm systems using the same logic and control relay interface.
Physical Setup Requirements
A Teltonika router must be installed and available on-site, along with its corresponding I/O adapter. For more details on how this adapter works, visit [Teltonika website].
Route the control cable from the location's control relay to the Teltonika router's I/O adapter.
Connect one terminal of the relay to Pin 3 (Digital Input) of the I/O adapter.
Connect the other terminal of the relay to Pin 1 (+VDC Power Supply).
Prepare the meter cabinet for the ripple control receiver in accordance with the grid operator's requirements.
Required circuit diagram: