Frequency Restoration Reserve (FRR)
European Union Electricity Market Glossary

 


 

 

According to Article 3(2)(7) of the Network Code on System Operation ‘Frequency Restoration Reserves’ or ‘FRR’ means the active power reserves available to restore system frequency to the nominal frequency and, for a synchronous area) consisting of more than one LFC area, to restore power balance to the scheduled value.

 

This category includes operating reserves with an activation time typically up to 15 minutes (depending on the specific requirements of the synchronous area).

 

Operating reserves of this category are typically activated centrally and can be activated automatically or manually (see the general requirements for Standard Products for Balancing Capacity in the EU Internal Electricity Balancing Market) 

 

In application of parameters of Balancing Capacity Standard Products the different categories of Balancing Capacity will have at least the following common characteristics:

 

a. For Automatic Frequency Restoration Reserves (aFRR):

 

- According to the draft Network Code on Load Frequency Control and Reserves (NC LFCR - substituted at the drafting stage by the Network Code on System Operation) requirements and, as aFRR is used to restore frequency, Full Activation Time and deactivation period for Central Europe was required not to be more than 15 minutes (900s), but could be shorter, depending of the needs of the TSOs in the Coordinated Balancing Area (CoBA).

 

This time duration depends on the Synchronous Area.

 

- The minimum Delivery Period shall be as small as possible and 10s is a target.

 

- The maximum Delivery Period shall be equal to the Validity Period duration.

 

- Mode of Activation shall be automatic.

 

- The product shall be divisible (10s time step and 1 MW power step).

 

As the ENTSO-E NC EB Supporting Document of 6 August 2014 (p. 57) underlines, bids for aFRR are exclusively available for maintaining the Active Power balance and not for other purposes, amongst others due to their specific requirements and different way of activation.

 

b. For Manual Frequency Restoration Reserves (mFRR):

 

- Requirements and as mFRR is used to restore frequency, Full Activation Time and deactivation period for Central Europe shall not be more than 15 minutes (900s), but can be shorter, depending of the needs of the TSOs in CoBA. This time duration depends on the Synchronous Area.

 

- Mode of Activation shall be manual.

 

For FRR the European integration model for a future EU-wide Balancing Market (i.e. activation of Balancing Energy) is intended to be based on a TSO-TSO Model.

 

The average price for the Frequency Restoration Reserve has a vital and commercially sensitive interconnectedness with the Imbalance Price. The Network Code on the Electricity Balancing stipulates that:

 

1. The Imbalance Price for shortage must not be less than:

 

(a) the weighted average price for activated positive Balancing Energy for Frequency Restoration Reserves and Replacement Reserves (RR); or

 

(b) in the event that no activation of Balancing Energy in either direction has occurred during the Imbalance Settlement Period, the value of the avoided activation of Balancing Energy for Frequency Restoration Reserves or Replacement Reserves.

 

2. The Imbalance Price for surplus must not be greater than:

 

(a) the weighted average price for activated negative Balancing Energy for Frequency Restoration Reserves and Replacement Reserves; or

 

(b) in the event that no activation of Balancing Energy in either direction has occurred during the Imbalance Settlement Period, the value of the avoided activation of Balancing Energy for Frequency Restoration Reserves or Replacement Reserves.

 

3. Imbalance Settlement Price, in the event that both positive and negative Balancing Energy for Frequency Restoration Reserves or Replacement Reserves have been activated during the same Imbalance Settlement Period, is to be determined for shortage and surplus based on at least one of the above principles.

 

The Agency for the Cooperation of Energy Regulators (ACER) in its Recommendation No 03/2015 of 20 July 2015 on the Network Code on Electricity Balancing proposes that all Transmission System Operators (TSOs) should implement the Regional Integration Models (RIMs) and European Integration Models (EIM) for mFRR.

 

In the Agency's opinion all TSOs currently operate mFRR process and therefore all TSOs should be part of the RIM and EIM.

 

In the ACER's opinion, RIM and EIM for aFRR should be implemented in line with the obligations stated in the NC LFCR (i.e. Network Code on System Operation).

 

The Agency expects that these obligations will require all TSOs operate the aFRR process, except for Great Britain, Ireland and Northern Ireland, where the implementation of the aFRR process is subject to a cost-benefit analysis to determine whether these TSOs should implement it.

 

The Agency considers that the overall number of CoBAs for regional implementation of aFRR and mFRR should be minimised as far as possible and fully justified by ENTSO-E to support their eventual merging.

 

The Agency recommends the overall number of CoBAs not to be higher than five and that each TSO is attributed to only one CoBA for each RIM.

 

This suggestion is driven by the objective to have large areas creating integrated and liquid balancing markets and also considers the practical aspects of the transition from RIM to EIM within the defined time periods.

 

The Agency also expects that CoBAs are defined in a consistent manner, which ensures efficient functioning of regional balancing markets, prevents delays in implementation projects in RIM, and facilitates the convergence and merging of CoBAs into each final EIM.

 

In the Agency's views, having consistent CoBAs means that the very large CoBAs defined for a given process may encompass a number of CoBAs defined for other processes.

 

For instance, the single CoBAs covering the whole Continental Europe Synchronous Area for the Imbalance Netting Process may cover a number of smaller CoBAs defined for the aFRR process, whereas each CoBAs for mFRR may encompass one or several CoBAs for aFRR or CoBAs for Replacement Reserves (RR).

 

The Agency also proposes to amend the Network Code on Electricty Balancing so that it explicitly states which Member States are included in each of the CoBAs for RR, mFRR and aFRR.

 

Provisions regulating Frequency Containment Reserve are stipulated in Articles 157 - 159 of the Network Code on System Operation (see box below). 

 

 

 

Network Code on System Operation

 

Title 6

Frequency Restoration Reserves

 

Article 157

FRR dimensioning

 

1. All TSOs of a LFC Block shall set out FRR dimensioning rules in the LFC Block operational agreement.

 

2. The FRR dimensioning rules shall include at least the following:

 

(a) all TSOs of a LFC block in the CE and Nordic synchronous areas shall determine the required reserve capacity of FRR of the LFC block based on consecutive historical records comprising at least the historical LFC block imbalance values. The sampling of those historical records shall cover at least the time to restore frequency. The time period considered for those records shall be representative and include at least one full year period ending not earlier than 6 months before the calculation date;

 

(b) all TSOs of a LFC block in the CE and Nordic synchronous areas shall determine the reserve capacity on FRR of the LFC block sufficient to respect the current FRCE target parameters in Article 128 for the time period referred to in point (a) based at least on a probabilistic methodology. In using that probabilistic methodology, the TSOs shall take into account the restrictions defined in the agreements for the sharing or exchange of reserves due to possible violations of operational security and the FRR availability requirements. All TSOs of a LFC block shall take into account any expected significant changes to the distribution of LFC block imbalances or take into account other relevant influencing factors relative to the time period considered;

 

(c) all TSOs of a LFC block shall determine the ratio of automatic FRR, manual FRR, the automatic FRR full activation time and manual FRR full activation time in order to comply with the requirement of paragraph (b). For that purpose, the automatic FRR full activation time of a LFC block and the manual FRR full activation time of the LFC block shall not be more than the time to restore frequency;

 

(d) the TSOs of a LFC block shall determine the size of the reference incident which shall be the largest imbalance that may result from an instantaneous change of active power of a single power generating module, single demand facility, or single HVDC interconnector or from a tripping of an AC line within the LFC block;

 

(e) all TSOs of a LFC block shall determine the positive reserve capacity on FRR, which shall not be less than the positive dimensioning incident of the LFC block;

 

(f) all TSOs of a LFC block shall determine the negative reserve capacity on FRR, which shall not be less than the negative dimensioning incident of the LFC block;

 

(g) all TSOs of a LFC block shall determine the reserve capacity on FRR of a LFC block, any possible geographical limitations for its distribution within the LFC block and any possible geographical limitations for any exchange of reserves or sharing of reserves with other LFC blocks to comply with the operational security limits;

 

(h) all TSOs of a LFC block shall ensure that the positive reserve capacity on FRR or a combination of reserve capacity on FRR and RR is sufficient to cover the positive LFC block imbalances for at least 99 % of the time, based on the historical records referred to in point (a);

 

(i) all TSOs of a LFC block shall ensure that the negative reserve capacity on FRR or a combination of reserve capacity on FRR and RR is sufficient to cover the negative LFC block imbalances for at least 99 % of the time, based on the historical record referred to in point (a);

 

(j) all TSOs of a LFC block may reduce the positive reserve capacity on FRR of the LFC block resulting from the FRR dimensioning process by concluding a FRR sharing agreement with other LFC blocks in accordance with provisions in Title 8. The following requirements shall apply to that sharing agreement:

 

(i) for the CE and Nordic synchronous areas, the reduction of the positive reserve capacity on FRR of a LFC block shall be limited to the difference, if positive, between the size of the positive dimensioning incident and the reserve capacity on FRR required to cover the positive LFC block imbalances during 99 % of the time, based on the historical records referred to in point (a). The reduction of the positive reserve capacity shall not exceed 30 % of the size of the positive dimensioning incident;

 

(ii) for the GB and IE/NI synchronous areas, the positive reserve capacity on FRR and the risk of non-delivery due to sharing shall be assessed continually by the TSOs of the LFC block;

 

(k) all TSOs of a LFC block may reduce the negative reserve capacity on FRR of the LFC block, resulting from the FRR dimensioning process by concluding a FRR sharing agreement with other LFC blocks in accordance with the provisions of Title 8. The following requirements shall apply to that sharing agreement:

 

(i) for the CE and Nordic synchronous areas, the reduction of the negative reserve capacity on FRR of a LFC block shall be limited to the difference, if positive, between the size of the negative dimensioning incident and the reserve capacity on FRR required to cover the negative LFC block imbalances during 99 % of the time, based on the historical records referred to in point (a);

 

(ii) for the GB and IE/NI synchronous areas, the negative reserve capacity on FRR and the risk of non-delivery due to sharing shall be assessed continually by the TSOs of the LFC block.

 

3. All TSOs of a LFC block where the LFC block comprises more than one TSO shall set out, in the LFC block operational agreement, the specific allocation of responsibilities between the TSOs of the LFC areas for the implementation of the obligations established in paragraph 2.

 

4. All TSOs of a LFC block shall have sufficient reserve capacity on FRR at any time in accordance with the FRR dimensioning rules. The TSOs of a LFC block shall specify in the LFC block operational agreement an escalation procedure for cases of severe risk of insufficient reserve capacity on FRR in the LFC block.

 

Article 158

FRR minimum technical requirements

 

1. The FRR minimum technical requirements shall be the following:

 

(a) each FRR providing unit and each FRR providing group shall be connected to only one reserve connecting TSO;

(b) a FRR providing unit or FRR providing group shall activate FRR in accordance with the setpoint received from the reserve instructing TSO;

(c) the reserve instructing TSO shall be the reserve connecting TSO or a TSO designated by the reserve connecting TSO in an FRR exchange agreement pursuant to Article 165(3) or 171(4);

(d) a FRR providing unit or FRR providing group for automatic FRR shall have an automatic FRR activation delay not exceeding 30 seconds;

(e) a FRR provider shall ensure that the FRR activation of the FRR providing units within a reserve providing group can be monitored. For that purpose, the FRR provider shall be capable of supplying to the reserve connecting TSO and the reserve instructing TSO real-time measurements of the connection point or another point of interaction agreed with the reserve connecting TSO concerning:
(i) time-stamped scheduled active power output;
(ii) time-stamped instantaneous active power for:
— each FRR providing unit,
— each FRR providing group, and
— each power generating module or demand unit of a FRR providing group with a maximum active power output larger than or equal to 1,5 MW;

(f) a FRR providing unit or FRR providing group for automatic FRR shall be capable of activating its complete automatic reserve capacity on FRR within the automatic FRR full activation time;

(g) a FRR providing unit or FRR providing group for manual FRR shall be capable of activating its complete manual reserve capacity on FRR within the manual FRR full activation time;

(h) a FRR provider shall fulfil the FRR availability requirements; and

(i) a FRR providing unit or FRR providing group shall fulfil the ramping rate requirements of the LFC block.

 

2. All TSOs of a LFC block shall specify FRR availability requirements and requirements on the control quality of FRR providing units and FRR providing groups for their LFC block in the LFC block operational agreement pursuant to Article 119.

 

3. The reserve connecting TSO shall adopt the technical requirements for the connection of FRR providing units and FRR providing groups to ensure the safe and secure delivery of FRR.

 

4. Each FRR provider shall:

(a) ensure that its FRR providing units and FRR providing groups fulfil the FRR technical minimum requirements, the FRR availability requirements and the ramping rate requirements in paragraphs 1 to 3; and

(b) inform its reserve instructing TSO about a reduction of the actual availability of its FRR providing unit or its FRR providing group or a part of its FRR providing group as soon as possible.

 

5. Each reserve instructing TSO shall ensure the monitoring of the compliance with the FRR minimum technical requirements in paragraph 1, the FRR availability requirements in paragraph 2, the ramping rate requirements in paragraph 1 and the connection requirements in paragraph 3 by its FRR providing units and FRR providing groups.

 

Article 159

FRR prequalification process

 

1. By 12 months after entry into force of this Regulation each TSO shall develop a FRR prequalification process and shall clarify and make publicly available its details.

 

2. A potential FRR provider shall demonstrate to the reserve connecting TSO or the TSO designated by the reserve connecting TSO in the FRR exchange agreement that it complies with the FRR minimum technical requirements in Article 158(1), the FRR availability requirements in Article 158(2), the ramping rate requirements in Article 158(1) and the connection requirements in Article 158(3) by completing successfully the prequalification process of potential FRR providing units or FRR providing groups, described in paragraphs 3 to 6 of this Article.

 

3. A potential FRR provider shall submit a formal application to the relevant reserve connecting TSO or the designated TSO together with the required information of potential FRR providing units or FRR providing groups. Within 8 weeks from receipt of the application, the reserve connecting TSO or the designated TSO shall confirm whether the application is complete. Where the reserve connecting TSO or the designated TSO considers that the application is incomplete they shall request additional information and the potential FRR provider shall submit the additional required information within 4 weeks from the receipt of the request. Where the potential FRR provider does not supply the requested information within that deadline, the application shall be deemed to be withdrawn.

 

4. Within 3 months after the reserve connecting TSO or the designated TSO confirms that the application is complete, the reserve connecting TSO or the designated TSO shall evaluate the information provided and decide whether the potential FRR providing units or FRR providing groups meet the criteria for a FRR prequalification. The reserve connecting TSO or the designated TSO shall notify their decision to the potential FRR provider.

 

5. The qualification of FRR providing units or FRR providing groups by the reserve connecting TSO or the designated TSO shall be valid for the entire LFC Block.

 

6. The qualification of FRR providing units or FRR providing groups shall be re-assessed:
(a) at least once every 5 years; and
(b) where the technical or availability requirements or the equipment have changed.

 

7. To ensure operational security, the reserve connecting TSO shall have the right to exclude FRR providing groups from the provision of FRR based on technical arguments such as the geographical distribution of the power generating modules or demand units belonging to a FRR providing group.

 

 

 

 

IMG 0744

    Documentation    

 

 

 

Network Code on System Operation, Article 3(2)(7), Articles 157 - 159

 

 

 

 

clip2

    Links    

 

 

 

 

Balancing Energy

 

Frequency Containment Reserve (FCR)

 

Replacement Reserve (RR)

 

 

 

 

 

Advertisements


 

 

 

 

 

Last Updated on Monday, 25 September 2017 21:04
 

Search

Copyright © 2009 - 2017 Michal Glowacki. All rights reserved.
The materials contained on this website are for general information purposes only and are subject to the disclaimer