Ancillary services

What are ancillary services?


Remunerated ancillary services cover two service categories :

  • frequency ancillary services which integrate frequency containment reserve and automatic frequency restoration reserve
  • voltage ancillary services which consolidate primary and secondary voltage regulation and also the specific processing of the synchronous compensation.

A description of these controls can be found in RTE's Technical Reference Documentation (article 4.1 for frequency control and article 4.2.1 for power control).

Frequency ancillary service rules :


The frequency ancillary service rules determine the procedures for participation in frequency ancillary services and also payment for them by RTE. They have been approved by CRE in compliance with article L. 321-11 of the Energy Code.

The provision of frequency ancillary services is open to any prequalified capacity in continental France, irrespective of its technology and its connection point to the grid.

Frequency containment reserve is carried out with cross border auctions (www.regelleistung.net). Automatic frequency restoration reserve procurement is carried out with obligations issued to obliges remunerated with a regulated price of about 19 euros per MW and per hour. Over the counter exchanges between providers are allowed for both reserves.

A participant signs a participation agreement in the rules (model agreement in appendix 1 of the rules). Download the list of frequency ancillary services providers

Payment related to a frequency reserves failure due to a balancing operation on the balancing mechanism:


The frequency reserves terms and conditions determine a "payment related to a frequency reserves failure due to a balancing operation on the balancing mechanism” paid by the reserve providers to RTE.

This SA payment is revised on 1 April of each year Y, for the period running from 1 April of the year Y to 31 March of the year Y+1.

It is calculated as follows:

Where:

  • ΣA-1 Additional Costs SSY is the sum of the frequency reserves additional costs (EUR) of the year Y-1, determined in accordance with the MA-RE Terms and Conditions
  • ΣA-1 SSY reconstituted volumes is the sum of the frequency reserves reconstituted volumes for the year Y-1 (in hMW), determined in accordance with the MA-RE Terms and Conditions
  • ΣA-1 aVH + (1−a)VB is the sum, for all reserve providers, for all half-hourly intervals for the year Y-1 and for all types of reserve, of the volumes V, as defined in Article 11.3.2 (in hMW), where VU is the upward volume and VD is the downward volume
  • a is the ratio of payment increase/decrease established in accordance with Article 11.2.3

S computing for the year 2019


  • Sum of additional costs SSY for 2018: €15,913,793
  • Sum of SSY reconstituted volumes in 2018: 454,275 hMW
  • 2018 balance: + €751,769 (as a reminder, the 2017 balance was - €910,610.99)
  • S2019 = 35.72 €/hMW

Voltage ancillary service rules :


The voltage ancillary service rules determine the procedures for participation in voltage ancillary services and also payment for them by RTE. They have been approved by CRE in compliance with article L. 321-11 of the Energy Code.

For voltage regulation, remuneration is made up of a fixed part and a variable part. It varies according to the over-sizing of the alternator, of the type of voltage regulation and the geographical area. Participation is possible for sites connected to the transmission grid.

A participant signs a participation agreement in the rules (model agreement in appendix 1 of the rules).