Market-based procurement of inertia of local grid stability

The first consultation of the procurement concept was initiated by the BNetzA on September 29, 2023, the second consultation started one year later on September 12, 2024. The final determination of the procurement concept by the BNetzA is currently still pending.

What is Inertia of local grid stability?

Inertia of local grid stability is an inherent reaction to an active power imbalance in order to prevent a violation, even if only local, of frequency stability limits, which can be critical for grid stability. Inherent reaction means in particular the Inertia from synchronous machines (rotating mass) or grid-forming converters (synthetic rotating mass), which has the aim of limiting frequency gradients. The Inertia reacts instantaneously to short-term changes in the voltage angle, counteracts the active power imbalance and limits the frequency gradient at the origin.

Market design (status of 2nd market consultation)

The procurement of Inertia takes place via a fixed price system that remunerates the provision of iInertia. The level of remuneration depends on the availability of the unit in the respective billing period, the procurement region and the product offered. The fixed price is determined on the basis of a methodology drawn up by an independent expert.

The products are differentiated according to direction (positive / negative) and availability (basic / premium), resulting in four different products.

Once defined, the inertia of local grid stability procurement concept regulates the framework for

  • Remuneration requirements
  • Product definitions
  • Deadlines
  • Availability
  • Framework conditions for pricing
  • Remuneration
  • Publication obligations of the procuring TSO


Further information

On November 28, 2024, the TSOs presented the draft of the procurement concept dated September 12, 2024 (status of second consultation) in a stakeholder workshop. The slides are available at the following link (in german language):

Set of slides Stakeholder workshop Procurement concept inertia of local grid stability November 2024 (in German)

Q&A on the inertia of local grid stability procurement procedure

Here, the 4ÜNB publish answers to provider questions of general interest in anonymized form at regular intervals. Provider questions can be addressed to the network operators using the contact details below.In addition to the new questions and answers, the previous ones are also included in the new publications. However, past answers may be supplemented in new publications, and this will be indicated separately.

Contact with the TSOs

If you have any questions about the market-based procurement of inertia of local grid stability, please contact the responsible TSO: