Today, ACER releases its Opinion on the National Resource Adequacy Assessment of Estonia. This is the first ACER Opinion on a National Resource Adequacy Assessment (NRAA).

What is a resource adequacy assessment?

The European Resource Adequacy Assessment (ERAA) identifies potential concerns about electricity resource adequacy across the EU and provides an objective framework for assessing the need for additional national measures to ensure security of electricity supply. ERAA is carried out on an annual basis by the European Network of Transmission System Operators for Electricity (ENTSO-E) and reviewed by ACER. In May 2024, ACER approved ERAA for the first time.

Member States can complement the European analysis with their own national assessment (NRAA). While national assessments follow the ERAA methodology, they may introduce changes in terms of, for example:

• new information as it becomes available since the latest ERAA;
• national specificities that are not reflected in ERAA.

Why an ACER Opinion?

When a national assessment identifies new adequacy concerns, and the Member State informs ACER, ACER must issue an Opinion on the differences between the national and European assessments.

In some cases, ACER’s opinion can play a role in the capacity mechanism application process. This process includes:

• identifying the necessity for the State aid measure;
• drafting the market reform plan;
• designing the eventual State aid measure.

Once all steps are finalised, the Member State may offer additional remuneration to resources through the capacity mechanism to close the forecasted adequacy gap.

What are ACER findings?

• The Estonian NRAA includes elements that represent a positive benchmark for future national assessments by:
  • Modelling the relevant neighbouring countries (and ensuring the interconnected market is taken into account).
  • Using ERAA 2023 as a starting point to ensure consistency and comparability between the two assessments.
• The differences with some of the ERAA 2023 assumptions are justified, as the Estonian NRAA:
  • Incorporates new information about interconnector commissioning and renewable energy development.
  • Better reflects regional specificities concerning balancing reserves.
  • Includes a sensitivity analysis to illustrate the role of oil shale-based generation at national level.
• However, the application of the updated assumptions is inconsistent throughout the assessment. While they have been used to recalculate the resource adequacy risk, their impact on the market (e.g. whether investments in new resources can mitigate the adequacy risk) has not been evaluated.

What are the next steps?

Considering these findings, ACER recommends the Estonian Transmission System Operator to assess how the new assumptions may impact the market and, if necessary, to amend the NRAA. This will improve the consistency of the Estonian adequacy assessment and the robustness of its results.  

ACER approves Transmission System Operators’ (TSOs’) proposal to amend the methodology for calculating scheduled exchanges resulting from single day-ahead coupling (SDAC). The amendment, proposed by TSOs on 21 March 2024, was referred to ACER by the European National Regulatory Authorities (NRAs) on 24 May 2024.

The methodology describes how the scheduled exchanges between bidding zones, scheduling areas, and Nominated Electricity Market Operators’ (NEMOs’) trading hubs are calculated in the SDAC.

What are the amendments about?

TSOs deemed it necessary to improve the SDAC algorithm to enable the effective implementation of the 15-minute Market Time Unit (MTU) in the SDAC (required for January 2025).

The amendments will allow handling an increased volume of data within the limited calculation timeframe. To do so, a back-up functionality for the calculation of the scheduled exchanges between bidding zones was introduced.

To foster the implementation of the 15-minute MTU, ACER has also amended the single day-ahead coupling products methodology.

What are the next steps?

TSOs shall implement the amendments by the time the 15-minute MTU becomes operational in the SDAC (required in January 2025).

ACER approves Nominated Electricity Market Operators’ (NEMOs’) proposal to amend the single day-ahead coupling (SDAC) products methodology.

The methodology lists all products that are eligible for inclusion within the EU single day-ahead coupling.

What are the amendments about?

NEMOs deemed it necessary to amend the SDAC products methodology to:

• enable the implementation of the 15-minute Market Time Unit (MTU) products into the SDAC;
• remove entry barriers for those market participants trading 15-minute MTU products; and
• allow them to buy and sell electricity for each 15 minutes during the day, enhancing market flexibility.

In its Decision 13-2024, ACER has revised NEMOs’ proposal and agreed to introduce a clear division between product categories, as well as to improve the overall structure and clarity of the document.

To foster the implementation of the 15-minute MTU, ACER has also amended the methodology for calculating scheduled exchanges resulting from single day-ahead electricity market coupling.

What are the next steps?

NEMOs shall implement the amendments by the time the 15-minute MTU becomes operational in the SDAC (required by January 2025).

The Regulation on Wholesale Energy Market Integrity and Transparency (REMIT) aims to prevent and protect consumers and businesses against market abuse in the European electricity and gas markets. The rules were amended in May 2024 to ensure they keep pace with evolving market dynamics.

In April and in July 2024, ACER published two open letters and addressed questions from stakeholders to help them comply with the new obligations under the revised REMIT. This open letter aims to offer further clarification on:

• how EU representatives for third-country market participants (e.g. not based in the EU) should be designated;
• the new obligations for PPAETs.

Why is the open letter relevant?

This open letter outlines what is expected from non-EU market participants (Annex I) and PPAETs (Annex II) to ensure compliance with the revised REMIT (Articles 9 and 15) and meet the new obligations.

Non-EU market participants:

• By 8 November 2024, non-EU market participants must notify their representative's contact details (name, email, postal address, phone number, and a written mandate of the designated representative) to ACER and the relevant NRA (e.g. the NRA of the Member State where the designated representative is established).
• Market participants can notify obligations via CEREMP. In Italy, Romania, and Slovenia, notifications must be made directly to the NRA, which will also serve as notification to ACER.

PPAETs:

• PPAETs are responsible for identifying and notifying ACER and the relevant NRAs about any potential breaches of insider trading (Articles 3), publication of insider information (Article 4), or market manipulation (Article 5) of REMIT. They must maintain effective arrangements, systems and procedures to detect these breaches, while ensuring compliance with the revised REMIT’s requirements.
• The obligations for persons professionally arranging transactions under Article 15(1) became applicable on 7 May 2024. However, obligations for persons professionally executing transactions under Article 15(2) will apply from 8 November 2024 onwards.

ACER invites market participants to read this letter alongside previous ones for a complete understanding.

What are the next steps?

By the end of 2024, ACER plans to revise the existing ACER Guidance on the application of REMIT to reflect the changes introduced by the revised REMIT.

For additional questions, ACER encourages market participants and PPAETs to use the REMIT query form.

Learn more about REMIT.

In November 2023, ACER received a proposal from Nominated Electricity Market Operators (NEMOs) for amending the ACER’s 2020 methodology for the price coupling algorithm and the continuous trading matching algorithm.

The methodology sets the regulatory framework for:

• the algorithms used for matching orders; and
• allocating cross-zonal capacities in the European day-ahead and intraday electricity markets.

After consulting with stakeholders (in winter and spring) and hosting two webinars (in February and June), ACER made revisions to the NEMOs’ initial proposal. Today, with its Decision 11-2024, ACER has adopted the amended methodology.

What’s new?

The updated methodology, in particular the day-ahead coupling algorithm, enables the investigation of a co-optimised allocation of cross-zonal capacity (‘co-optimisation’). This approach would allow the efficient sharing of the available cross-zonal capacity between energy trading and exchanges linked to balancing services, facilitating the integration of balancing capacity markets.

Research will identify the best co-optimisation approach

ACER’s Decision requires NEMOs, in collaboration with Transmission System Operators (TSOs), to conduct the necessary research and development (R&D) activities to fully understand the technical feasibility, impacts, and implications of integrating co-optimisation into the price coupling algorithm. This R&D work will be structured around four milestones and is expected to finish in November 2026.

ACER expects the R&D outcomes to provide sufficient information to determine the best approach for implementing co-optimisation and estimate a realistic timeline for its introduction in the day-ahead electricity market.

What are the next steps?

After the required R&D activities are finalised, ACER will analyse the findings and discuss their implications with NEMOs and TSOs. Based on these discussions and if required, ACER may request further amendments to the algorithm methodology and related Terms, Conditions and Methodologies (TCMs).

The Comisión Nacional de los Mercados y la Competencia (CNMC) has imposed a €1 million fine on Enérgya VM Gestión de Energía, S.L.U. for manipulating the Spanish gas market.

This penalty comes under the REMIT Regulation (EU) No 1227/2011, which prohibits market manipulation and seeks to protect the integrity and transparency of the EU’s wholesale energy markets.

In its decision, CNMC found that Enérgya VM Gestión de Energía had breached Article 5 of REMIT, specifically Article 2.2.a.ii, in artificially setting the price by marking the reference ‘precio último diario’ (last daily price) for the Mibgas Spanish product D+1 across 32 trading sessions from 1 September to 31 December 2022.

The investigation revealed that Enérgya VM Gestión de Energía placed purchase orders without the intention of executing them, with bids entered between 0 and 7 seconds before the trading session’s closing. This behaviour minimised the risk of the Enérgya VM Gestión de Energía bids being matched by other market participants.

As a result of Enérgya VM Gestión de Energía’s actions, in the 32 trading sessions reported the closing bid-ask spread was reduced, impacting the calculation method of the last daily price that resulted artificially inflated.

ACER welcomes this decision by CNMC, which seeks to promote the transparency and integrity of the Spanish natural gas market.

Access the Decision and CNMC’s press release (both in Spanish).

See the latest table of REMIT breach sanction decisions adopted by national regulatory authorities.

Check the ACER REMIT Guidance (6th edition) for more information on the types of trading practices which could constitute market manipulation under REMIT.

Interested in further information on enforcement decisions under REMIT? Check out ACER’s REMIT Quarterly reports.