ACER amends the EU electricity single intraday coupling products methodology to enhance market flexibility

ACER amends the EU electricity single intraday coupling products methodology to enhance market flexibility
What is it about?
With its Decision 03-2025, ACER has approved a proposal from Nominated Electricity Market Operators (NEMOs) to amend the single intraday coupling (SIDC) products methodology.
Why is single intraday market coupling important?
Before ‘market coupling’ was introduced in the EU, cross-border power grid capacity and electricity had to be bought separately. Now, market coupling (day-ahead and intraday) allocates scarce cross-border grid capacity efficiently by coupling wholesale electricity markets in different regions, while taking into account cross-border power grid constraints.
With the growth in intermittent renewables (e.g. wind and solar), there is a growing interest in intraday trading for market participants to be in balance after the closure of the day-ahead market and as close to real time as possible. This flexibility benefits both market participants and power systems.
What is the methodology about?
The SIDC products methodology is defined by the Capacity Allocation and Congestion Management (CACM) Regulation. The methodology specifies the types of products that can be traded within the EU’s continuous single intraday market and in intraday auctions. Here, trading begins the day before delivery and continues through the day of delivery, supporting real-time adjustments to supply and demand across borders.
Why did ACER amend the methodology and what’s new?
The update aligns the SIDC products methodology with the single day-ahead coupling (SDAC) products methodology (amended in September 2024 to allow 15-minute trading). With this change, market participants will be able to trade electricity in 15-minute intervals in both day-ahead and intraday markets, resulting in enhanced market flexibility.
Harmonising trading rules across both markets is necessary to comply with the EU Electricity Regulation and reduce entry barriers for market participants trading short-term products.
What are the next steps?
NEMOs are required to implement the amendments promptly after adoption.