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What are balancing services?

What are balancing services?

In short, balancing services are a type of ancillary service used to keep the frequency in the power grid stable at 50.0 Hertz.

The power grids of most European countries on the European mainland are interconnected and operate at a common grid frequency of 50.0 Hertz. To keep the frequency stable at 50.0 Hertz, the grid supply (generation) must match the grid consumption (load) at all times.

Capacity-frequency scale

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A distinction is made between the terms balancing services, balancing capacity, and balancing energy. Balancing services is the general term for balancing capacity and balancing energy. Balancing capacity describes the availability of capacity for system stabilization, and balancing energy is the actual amount of energy activated and utilized in the event of frequency deviations.

Due to fluctuations in generation and load, transmission system operators (TSOs) use balancing services to balance these discrepancies. There are three types of balancing services:

    • FCR – Frequency Containment Reserve 
    • aFRR – automatic Frequency Restoration Reserve
    • mFRR – manual Frequency Restoration Reserve


The three types of balancing services primarily differ in their activation speed and product length, which leads to different product-specific requirements. A more detailed description of the three types can be found under: What types of balancing services are there?

What types of balancing services are there?