PC_2024_E_04 - Public consultation on the implementation of co-optimisation in the electricity day-ahead coupling algorithm

Policy area
Electricity, capacity allocation and congestion management, electricity balancing
Contact information
Market participants, nominated electricity market operators, transmission system operators, regulatory authorities, academics in the EU and EEA

Contact information


On 24 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 bids from market participants and allocating cross-zonal capacities in the European day-ahead and intraday electricity markets.

Amending the methodology, in particular the day-ahead coupling algorithm, is needed to enable a co-optimised allocation of cross-zonal capacity for the exchange of balancing capacity or sharing of reserves. This would facilitate the integration of the balancing capacity markets and allow for a more efficient use of cross-zonal capacity.

Why we are consulting

Following the receipt of the NEMOs’ proposal in November 2023, ACER initiated a procedure to decide on the proposed amendments within six months. To collect inputs from relevant stakeholders and inform its decision-making process, ACER ran a public consultation and hosted a workshop in early 2024.

In October 2023, ACER commissioned a consultancy study to assess the expected benefits of implementing co-optimisation in the day-ahead coupling algorithm as compared to the current market design. The study includes insights on the design of bids that would allow to best capture the interactions between day-ahead and balancing capacity markets, while maximising the expected benefits of co-optimisation. The study could not be completed in time to be part of ACER’s public consultation in early 2024. It will be published on 27 May 2024.

For this reason, and based on stakeholders’ input gathered so far, ACER conducts a second public consultation (from 27 May to 19 June 2024). This consultation aims to gather stakeholders’ perspectives on the study’s findings and identify further research and development necessary for implementing co-optimisation.

ACER will consider the consultation and webinar outcomes when drafting the proposed amendments to the methodology.

ACER will also organise a webinar on 10 June 2024 to explore the study’s key findings, discuss opportunities and challenges of implementing co-optimisation, and engage with experts.

Next steps

ACER expects to decide on the amended methodology for the price coupling algorithm and the continuous trading matching algorithm by early autumn 2024.