Real-time interface frequently asked questions (FAQ)

Read all about the mandatory direct control of energy assets by the grid operator with the real-time interface

An overview of many questions about the real-time interface

Scope of application real-time interface

Netbeheer Nederland: “With the energy transition, a large-scale emergence of sustainable generation installations in the distribution networks of regional grid operators is visible. This development ensures the return of large powers to grid parts that were not originally designed for this. This has already led to congestion problems and transport restrictions in many places. The purpose of the interface is to enable collaboration between generators and grid operators to increase and better utilize transport capacity and safely maintain the electricity network.”

The real-time interface is mandatory for generation installations with an installed capacity between 1 and 50 MW. That is category B of the European Regulation Requirement for Generators (RfG) . At a later stage, the real-time interface will be developed for the other categories: A, C and D.

The initial focus is on new generation installations in areas with existing and threatened grid congestion and installations connected to HS/MS and MS/MS stations. For the most current overview, see: capacity map of Netbeheer Nederland .

  • Under certain circumstances, the grid operator can switch off a generating installation. For example, in the event of acute congestion, carrying out congestion management or if there is no longer any redundancy in the network due to work. Of course there is a compensation for this.


The three largest grid operators Stedin, Enexis and Liander will start testing in Q1 2023.

From 2024, the real-time interface will be mandatory for new generation installations with a capacity greater than 1 MW. The grid operator can also make the real-time interface mandatory if this is necessary to carry out its statutory tasks. Or for adjusting production in the event of maintenance work in sub-grids where the disruption reserve has been used for the transport of production.

Real-time interface funtionnality

Article 14.2, part b, of the European RfG legislation : ‘requirements for additional equipment that makes it possible to control the generated power remotely’ for the purpose of frequency maintenance or influencing transport capacity.

The customer endpoint must be able to receive and process the control signal from the grid operator in accordance with IEC-61850. As a connected party, it is desirable that this functionality is combined with the additional control signals in order to participate in TenneT’s balancing markets.

The grid operator is responsible for the DSO endpoint. The customer is responsible for the customer endpoint and the cable to the DSO endpoint.

All equipment from the grid up to the transfer point of the connection is the property of the grid operator. Everything from this point within the connection is the property of the generator (connected party). The generator is therefore responsible for providing a functioning customer endpoint.

The owner of a generation installation must provide a certified customer endpoint to which the DSO connects. The Teleport is a certified Customer endpoint. After the Teleport is added to the installation, the generating installation can be put into operation.

A controller (such as the Teleport) to receive and process the signal to the generation installation, a measuring system to measure the load at the transfer point and connectivity so that cybersecurity updates can be carried out.

The Teleport can handle >200 asset protocols, including the most commonly used PV park controllers and wind turbine systems. See the full list of compatible assets:

In a logical and safe place for the connected person from which a connection can be made to the DSO endpoint.

The affiliate must take care of the purchase and installation of the customer endpoint. In some cases the grid operator will have to take care of this.

Every generation installation has a delivery process before it can be put into use. The RTI will be part of the delivery process. Currently, the RTI is not yet part of the official delivery process (compliance verification document). After commissioning, a key signal can be sent periodically. If there is no correct response, the grid operator can contact the connected party.

The Teleport automatically creates a log of all activations performed by the network operator. This log is immediately available.

These things are separate from each other. However, direct switching by the grid operator has priority over any other switching action. The Teleport as a customer endpoint can clearly distinguish this.

Many PV inverters, even very old ones, are already set up to be controlled by a centralized control system. They provide a standard communication protocol with registers that can receive commands. Please check compatibility in the product manual or in the document describing the communication protocol. The Teleport is already linked to dozens of brands and hundreds of types.

Traditional generators are usually equipped with a built-in control system or an external PLC that controls their operation. As with PV inverters, the controller requires a standard communication protocol with registers that can be used to receive and process control signals. The customer endpoint is installed on this controller.

The generator will be compensated when the grid operator uses the real-time interface. The extent and manner depend on the application framework.

The connected party must provide an overview of the missed electricity generated and lost income. The certified Teleport can generate the necessary source data for this.


For version 1.0 via an Ethernet (RJ45) cable [Requirement: Bandwidth-1, [Network segmentation-1].

At the closed part of the MS room [Requirement: Physical-security-1].

The customer endpoint may not be directly accessible via the internet, only via secure access [Requirement: Contract-segmentation-1].

  • – Passwords must be unique and strong based on section 5 NIST SP 800-63B [Requirement: Contract-hardening-1].
  • – There must be a process to implement security updates remotely on the real-time interface. The following must be monitored: vulnerability lists, manufacturer notifications and new release notes. Patches and updates should be implemented immediately after compatibility testing. [Requirement: Contract updates-1, Customer updates-1].
  • – Cybersecurity training must be followed by the administrators of the customer endpoints [Requirement: Contract training-1].
  • – The Teleport and the processes meet these requirements

ISO 27001 is desirable for data protection and additional requirements as set out by the European Network for Cybersecurity (ENCS). The Teleport meets this requirement.

A maximum deviation of 10 seconds is allowed [Requirement: Accuracy-2, Accuracy-3]. The Teleport meets this requirement.

Testing and certifications

Because it is a national standard, the specifications are published on the Netbeheer Nederland website .

A cable must be run between the generating installation and the MSR room. This could be the Ethernet cable between the customer endpoint and the DSO endpoint or it could be the cable between the generating plant and the customer endpoint. The optimal setup depends on the type of generating set and equipment and the possible installation locations.

There will be an adjustment to the connection and transport agreement (ATO) between the connected party and the grid operator. This will include that there is a real-time interface.

Measurements and control signals

The functionality of the real-time interface is based on reading the powers and voltages at the transfer point and the possibility of sending control signals (set points). In most cases communication will take place using a protocol such as Modbus RTU or Modbus TCP. The Teleport as a customer endpoint already has most protocols of commonly used generation installations in its asset library.

The measurement data is requested by the DSO endpoint and sent to the grid operator. If the generation installation is close to the transfer point (taking cable resistances into account) and there is little self-consumption (impact on power), the measurement data from the generation installation can be used directly (if they meet the correct measurement class).

Measurement data must have a class 1 accuracy in line with IEC-61869 [Requirement: Accurarcy-1].

The customer endpoint for the real-time interface can also be used without separate measuring equipment if the generation installation meets the measuring class and is representative of the behavior at the transfer point.

The grid operator and the generator are each individually liable for the quality of the measurement data and any resulting damage.

  • Maximum generated power in % and as absolute value [MW] and the maximum consumed power in absolute value [MW]. [Requirement: Setpoint-1, Setpoint-2, Setpoint-3].
  • Reactive power in [MVAr] [Eis: Setpoint-5].
  • The reason why a setpoint was sent [Requirement: Setpoint-8].

Current power in MW, Current reactive power in MW, Current voltage on all phases in kV, Current current on all phases in A. [Requirement: Measurements-1, Measurements-2, Measurements-3, , Measurements-4].

  • If communication is no longer possible between the customer endpoint and the DSO endpoint after a set period, the generated power must be switched back. The established period and the safe-mode setpoint are determined in advance. [Requirement: Safe-mode-1].
  • The grid operator can remotely read and set these safe-mode setpoints in MW and % [Requirement: Safe-mode-2, Requirement: Safe-mode-3].
  • When communication is restored, the 15 minute average, minimum and maximum power values ​​of the past 8 hours must be sent [Requirement: Safe-mode-5, Safe-mode-6, Safe-mode-7].

The grid operator determines the frequency with which measuring signals are automatically sent (integrity reports). In addition, the grid operator can set it to receive measurements when there is a change in measurements (for example when power or voltage is lost) (data change).

The customer Endpoint must have an availability of at least 99% of the time measured over a period of 6 months in accordance with IEC-60870-4 class A1 [Requirement: Availability-1]. In addition, the DSO must be able to retrieve the status of the customer Endpoint. [Requirement: Customer-configuration-1]

Communication between the Endpoints may not take more than 4 seconds [Requirement: Response-time-1]. The maximum response time between the asset and the customer Endpoint varies per use case [Requirement: Response-time-2]. For the first use cases (acute congestion), the response times inherent to Modbus RTU and Modbus TCP protocols comply, among other things. The time to start up after different types of interruptions may take a maximum of 3 minutes [Requirement: Response-time-3, Response-time-5, Response-time-6, Response-time-8]

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