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Prequalification process

Prequalification process

Potential providers of balancing services must provide proof within the prequalification process that they meet the requirements necessary to ensure supply security for the provision of one or more types of balancing services.

These requirements include IT, product-specific, and technical requirements, which are checked as part of the prequalification process. All relevant documents are published alongside. 

The key elements of the prequalification include: 

  • Creation of IT and deliverance concepts, 
  • Performing the operating test, 
  • Conducting the control system test, 
  • Submission of certificates (e.g. Anschlussnetzbetreiber Bestätigung (ANB)). 

For all types of balancing services (FCR, aFRR, mFRR), the prequalification is carried out exclusively by the TSO in whose Load-Frequency Control (LFC) area the relevant technical units (power generation plants and/or consumption units) are connected to the grid, regardless of the voltage level (the so-called connecting TSO). You can find the key steps of the prequalification in the process diagram. 

IT-Concept

The transmission system operators (TSOs) have defined uniform requirements for the information technology used by companies providing balancing services. These are found in the form of "IT Mindestanforderungen EN" 

Due to their system responsibility, TSOs generally maintain high requirements for the confidentiality, availability, and integrity of their infrastructures and information, which extend to all connected infrastructures and service providers. The requirements represent minimum standards for security and availability and provide further recommendations for achieving the desired goals.

Deliverance concept

The deliverance concept is the document in which the provider describes their provision and delivery. This includes, for example, the documentation of the technical implementation of the respective type of balancing services. You can find a guide for creating the concept here.

Operating test

The operating test is a trial provision of balancing services. It is essentially a practical test based on standardized criteria, used to check the technical suitability of a provider's units for providing balancing services. The operating test is documented in an operational log, which the balancing service provider submits with the application documents.

Control system test

The control system test is the final check performed by the connecting TSO to verify that the provider's control system connects correctly to the TSO's control system. Parts of the test include checking the correct collection and delivery of individual data points, receiving and accurately implementing setpoint values, and verifying redundant data connections. 

The test is carried out in close coordination between the provider and the TSO and is intended for all types of balancing services. The prequalification documents are submitted to the relevant TSO using the PQ portal. Access to the PQ portal can be requested from the respective connecting TSO.

The PQ portal is the central cross TSO database for the prequalification of TE/RE/RG. It needs: 


  • Standardized collection and verification of the submitted data 
  • Accelerated, transparent, and simplified PQ process 
  • Application for access data from the connecting TSO necessary 

The current overview of prequalified capacity by balancing services is as follows. A more detailed list and a depiction of the development of prequalified capacity in Germany over the years can be found here.

Prequalified capacity (in GW) per primary energy source/category