+ RTE has adopted a proactive approach to managing these compensations and the associated corrections to balance perimeters. It has also launched a project to industrialise the compensation process.  This page will help you implement this change.

 

 

Beneficiaries

• HTB onshore renewable energy generators
• Balance Responsible Parties

Context

RTE may need to curtail the injection of onshore renewable energy due to transit constraints, particularly those related to the optimal sizing of the transmission network.

A curtailment refers to a modification in the power flow at the interface between RTE and its customers (CART-P or CART-D signatories). Limitations can be sent to:

• the THB generator
• the HTB lead customer of a Multi-Producer Group (which allocates sub-curtailments among the THB generators who have subscribed to the accounting service)
• the source substation at the interface between the transmission and distribution networks (the DSO then distributes the curtailment between the HTA generators connected to this source substation).

 

 

Distribution of curtailments carried out by RTE at customer substation level

 

Any curtailment may potentially cause damage for generators, resulting in an amount of Energy Not Dispatched (END) on the PTS. This could also affect the Balance Responsible Party due to an imbalance in their balance perimeter.

Curtailments on the PTS

The compensation process for HTB generators is divided into three stages:

Stage 1: Calculating eligibility

The first stage is to determine whether the curtailment qualifies for compensation, in accordance with the commitments set out in the generator system access contract (CART), the provisional management contract or the generator connection agreement.

This stage enables the following elements to be validated between the generator and RTE:

• the curtailment trace (period, setpoint, reason)
• its status: eligible for compensation / potentially eligible for compensation / not eligible for compensation.

It also makes it possible to collect information from the generator:

• any sites that have subscribed to the metering data service, to which the limit has been distributed.
• The tariff of the lead customer or the sites subscribed to the metering service, if they benefit from a support mechanism (with proof), such as a: Supply Obligation or Remuneration Supplement.

Stage 2: Calculating and valuing Energy Not Dispatched (END)

Energy Not Dispatched refers to the energy that the Customer is unable to inject into the PTS because of the curtailment. It is calculated, in accordance with Article 7.7 of the Technical Reference Documentation, as the difference between:

• the Reference Load Curve, corresponding to the generator's theoretical production in the absence of curtailment, estimated using the method described in the Technical Reference Documentation
• the Production Measurement Curve, corresponding to the generator's actual production as a result of the curtailment, taken from the metering data.

 

 

Calculating END

There are two methods for calculating the Reference Load Curve:

When these methods do not allow to calculate the Reference Load Curve, RTE may request a Reference Curve from the generator. This Generator Reference Load Curve will be sent using the predefined format provided by RTE and can be downloaded via the "Compensation for curtailment" API (see chapter “Planned Changes to industrialise the compensation process”). 

At the end of this stage, RTE asks the generator to validate the END of the curtailment.

The financial flows between the parties (including compensation for the generator) and the generator compensation tariffs applied by RTE in the two scenarios below, are described in Article 7.7 of the Technical Reference Documentation.

• Cases requiring balance perimeter correction

For limitations activated after 14 October 2024, a correction to the Balance Perimeter is implemented when the notice period for the curtailment is insufficient for the Balance Responsible Party to (re)balance their perimeter. Article 7.7 of the Technical Reference Documentation specifies the cases in which RTE corrects the balance perimeter by a quantity of energy equal to the previously evaluated amount of END.

Any claims on the part of the Balance Responsible Party regarding the value of END must be made via the generator.

In the event of iterations between RTE and the generator at the previous stage to determine an END value, the successive updates to the END will be incorporated into the various M+X correction deadlines for the balance perimeter, even before the generator’s final validation of the END.

The Balance Responsible Party has an incompressible 15-day period following any END update to submit a claim via the generator, even if the generator has validated the END before this 15-day period. This ensures the claim can be considered in the nominal compensation process. After this deadline, if the END has been validated by the generator, the claim will still be reviewed by RTE but outside the nominal process, potentially resulting in a longer processing time.

Ultimately, in the event of an imbalance, the cost of the imbalance will be allocated to RTE in the Imbalance Adjustment Account.

The financial flows between the parties, including compensation for the generator, following balance perimeter correction, vary depending on the support mechanism benefiting the generator, as described in Article 7.7 of the Technical Reference Documentation.

• Cases not requiring balance perimeter correction

When the curtailment is activated within the notice period, allowing the Balance Responsible Party to rebalance, RTE does not adjust the balance perimeter but compensates the generator for Energy Not Dispatched, in accordance with the CART-P contract. This compensation takes into account the feed-in tariffs the producer benefits from as part of its support mechanism.

Stage 3: Invoicing

Based on the financial flows established in the previous stage, the billing process occurs either between the generator and RTE or between the generator and its Balance Responsible Party

 

Curtailments on the PDS and impact on Balance Responsible Parties

The conditions for compensating MV generators are the responsibility of the Distribution System Operators, as specified in the MV generator's network access contract (CARD) with the distribution network. 

Eligibility for balance perimeter corrections is governed by the contractual framework of the relevant DSO.

In this framework, DSOs report all balance perimeter corrections to RTE caused by the curtailment of HTA sites on their network, regardless of whether the curtailment is activated for RTE's needs or for the DSO’s own requirements.

This data is used to account for HTA curtailments when correcting the balance perimeters of Balance Responsible Parties and to allocate the cost of imbalances in the Imbalance Adjustment Account to the DSO that initiated the curtailment request.

Planned Changes to industrialise the compensation process

Tools available to HTA generators:

By the end of 2025, generators will have access to:

• a "View and process curtailments" service deployed on the Services Portal
• a Data Portal API for "Compensation for Curtailment"

to facilitate the implementation of the data exchanges and validations necessary for the compensation process.

Link to the access conditions for the "View and process curtailments" service

Link to the description and access conditions for the "Compensation for Curtailment" API

Link to swagger for "Compensation for Curtailment” API

 

Tools available to Balance Responsible Parties:

By the end of 2025, Balance Responsible Parties will receive an email at the end of each month detailing the END at the site level, broken down into 5-minute intervals for each curtailment where a balance perimeter correction has been made.

Additionally, by the end of 2025, they will have access to a Services Portal service and a Data Portal API to view and download these records. This data will be available for a period of 5 years.

This service will also provide updates on the status of the generator’s END processing (validated or not) and indicate how it will be factored into the various M+X variance calculation deadlines.

Transition from the temporary solution to the target service by the end of 2025

The limitations available in the target service are as follows:

• Curtailments occurring after the introduction of the industrialised service (end of 2025)
• Previous curtailments that remain unresolved, meaning the volume of END is not yet final (for example, if it has not been calculated or validated by the generator).

During the transitional phase, Balance Responsible Parties may need to maintain a record of volumes corrected for HTB generator curtailments, received via email, as not all these volumes will necessarily be included in the target service.

Since March 2023, Balance Responsible Parties have had access to imbalances caused by HTA curtailments via the "See valued imbalances" service and its Big Imbalance API.

As of the application date of 14 October 2024, deviations caused by activated HTB curtailments have been aggregated with HTA curtailments in this service and API.

The gaps created by HTA and HTB curtailments are accessible:

• From the service by downloading the "Flexibility_Down" and "Flexibility_Up" files (former name until the end of March 2025:  “DSO Flexibility Down” and “DSO Flexibility Up”)
• From the API via the request for data types Y23 and Y25 

Link to Big Imbalance 3.0.4 API implementation guide, applicable on 1 April 2025

Reference documentation

• Technical Reference Documentation - Article 7.7  – Compensation for renewable energy curtailments: wind and onshore photovoltaics
• Technical Reference Documentation Article 8.13 - Standard outline of the contract for access to the Public Transmission System for CART-P generator customers
•  Technical Reference Documentation Article 8.8.1 - Contract relating to the Predictive Management of photovoltaic and wind generation
• Technical Reference Documentation Article 8.4 - Outline of the Connection Agreement for generators and/or storage providers - General and Special Conditions
• Market Rules - Chapter 3 - Balance Responsible Party (Correction of balance perimeters: 3.L.5.1.3) (Taken into account in the Imbalance Adjustment Account: 3.Q.5)

Contact

For any questions, please contact RTE-INDEMNISATIONLIMITATIONENR@rte-france.com