With the increase of electrical appliances with heavy energy consume, and the limited available power, the German government saw the need to take control over the power consumption.

A new regulation was implemented in January 2024 ‘The Energy Industry Act (EnWG)’. The §14a states that it is mandatory to install a control receiver.

If you already have a smart meter, you can check with your grid operator how this applies to you. Otherwise, the grid operator needs to be able to control your energy use, when the grid is heavy loaded. The reason for this regulation is to ensure grid stability and smart and flexible energy use.

The consequence can be that the grid operator will limit available power down to 4.2kW at times with high usage, impacting on how you can use energy. The regulation also applies to EV chargers that must be controllable by the grid operator.

DEFA has implemented solutions for how your EV charging can be controlled, offering flexibility and smart power use with DEFA Power.

When the Grid provider is limiting the available power, it can be a good option to have access to another energy source, e.g. solar energy. Alternatively, you need to optimize the use of your available power.

There are three solutions to choose from:

• With DEFA Power and Perific integration which also gives opportunity for Solar energy
  
• With Modbus with the opportunity to control several devices
  
• Cloud based with grid provider og back-end solution (OCPP2.0.1)
  

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Solution with Perific Max and DEFA Power

DEFA Power can be connected to the Perific Max device – a compact ripple control receiver that meets FNN specifications. It interprets the grid operator’s signals and triggers the corresponding control actions on the charging station

With Perific Max you can also control the use of solar energy to charge your EV. Read more here.

To get started:

• In addition to DEFA Power, you need the energy control unit Perific Max installed in your fuse cabinet. This unit will communicate with the FNN box from your grid provider.
  
• Download the DEFA Power app, to control charging. If you have Solar integrations you have several options with the app.

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Solution with Modbus TCP which also allows control of more of your electrical devices

A local Modbus-compatible controller receives control signals from the grid operator and forwards them to DEFA Power using the Modbus TCP protocol. This solution enables fast, reliable load management without relying on a cloud connection.​

Alternatively, if the FNN box installed in the system supports Modbus TCP and includes control functionality, it can serve directly as the Modbus controller. In this case, no additional control unit is required — the FNN box itself communicates with DEFA Power to fulfill §14a EnWG requirements. By installing a local Modbus TCP controller, e.g. Siemens LOGO! – this device will receive signals from the grid operator through the FNN box and adjust charging accordingly. 

With the Modbus solution, you can also control other devices such as electrical heat pumps and air conditioning systems.

• App control will depend on the solution provider. 

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Cloud-based solution with OCPP 2.0.1.

• Our Back-end solution partners or your grid operator can offer cloud-based control solutions.
• No installation in fuse cabinet needed
• App control depending on what the solution partner can offer. Check the partners that offer OCPP 2.0.1 support here

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Read more about §14 here.