Single Intraday Coupling (SIDC)

What is Single Intraday Coupling?

Single Intraday Coupling (SIDC) creates a single EU cross-zonal intraday electricity market. In simple terms, buyers and sellers of energy (market participants) are able to work together across Europe to trade electricity continuously on the day the energy is needed.

An integrated intraday market makes intraday trading more efficient across Europe by:

  • promoting competition
  • increasing liquidity
  • making it easier to share energy generation resources
  • making it easier for market participants to allow for unexpected changes in consumption and outages

As renewable intermittent production such as solar energy increases, market participants are becoming more interested in trading in the intraday markets. This is because it has become more challenging for market participants to be in balance (i.e. supplying the correct amount of energy) after the closing of the day-ahead market.

Being able to balance their positions until one hour before delivery time is beneficial for market participants and for the power systems alike by, among other things, reducing the need for reserves and associated costs while allowing enough time for carrying out system operation processes for ensuring system security.

How Single Intraday Coupling began

Single Intraday Coupling (SIDC) is a cooperation between Nominated Electricity Market Operators (NEMOs) and Transmission System Operators (TSOs) which enables continuous cross-border trading across Europe.

SIDC follows on from the XBID (Cross Border Intraday) project which delivered, in June 2018, the first go-live of the intraday continuous trading platform. It allows energy networks to integrate and expand across Europe.

SIDC was launched on 12/13 June 2018 across 15 countries. In the first 16 months of operation over 25 million trades were completed across the countries involved. In November 2019 and September 2021, SIDC went live across a further eight countries resulting in 23 countries being coupled.

SIDC is in line with the CACM (Capacity Allocation and Congestion Management) EU Target model for an integrated intraday market.

SIDC geographical scope and future go-live phases

SIDC will expand in several phases, also referred to as “waves”. The map below shows the geographic spread of the first, second and third waves which have been implemented. Further waves are planned and the scope may expand beyond that shown.

The table below lists the countries of the first, second, third and fourth waves.

1 st wave June 2018
  • Austria
  • Belgium
  • Denmark
  • Estonia
  • Finland
  • France
  • Germany
  • Latvia
  • Lithuania
  • Luxembourg
  • Norway
  • The Netherlands
  • Portugal
  • Spain
  • Sweden
2 nd wave November 2019
  • Bulgaria
  • Croatia
  • Czech-Republic
  • Hungary
  • Poland
  • Romania
  • Slovenia
3 rd wave September 2021
  • Italy
4 th wave November 2022
  • Greece
  • Slovakia


To accomplish SIDC, TSOs and NEMOs work in close collaboration.

The organisations involved are:

Transmission System Operators (TSOs):

50HERTZ, ADMIE, AMPRION, APG, AST, ČEPS, CREOS, EirGrid, ELERING, ELES, ELIA, ELSO, ESO, FINGRID, HOPS, Litgrid, MAVIR, PSE, REE, REN, RTE, SEPS, SONI, STATNETT, SVENSKA KRAFTNÄT, TenneT DE, TenneT NL, TERNA, TRANSELECTRICA and TransnetBW.

Nominated Electricity Market Operators (NEMOs):

BSP, CROPEX, EirGrid, EPEX SPOT, GME, HEnEx, HUPX, IBEX, Nord Pool, OKTE, OMIE, OPCOM, OTE, SONI and TGE.

How Single Intraday Coupling works

SIDC works on a common IT system with:

  1. a Shared Order Book (SOB),

  2. a Capacity Management Module (CMM), and

  3. a Shipping Module (SM).

This means that orders entered by market participants for continuous matching in one country can be matched by orders submitted by market participants in any other country as long as they are both within the project’s reach and transmission capacity is available.

The intraday solution supports continuous trading that is both:

  • explicit (capacity only. Note: only provided where requested by National Regulatory Authorities (NRAs) ie. at the French-German and the Croatian-Slovenian borders), and

  • implicit (capacity and energy together)

When market participants of each NEMO submit orders, they are put together in one Shared Order Book (SOB). In a similar way, TSOs make available all the intraday cross-border capacities in the Capacity Management Module (CMM).

This allows NEMOs to operate trading systems to show orders to market participants from other market participants in three groups:

  1. within the same NEMO

  2. from other NEMOs in the same market area

  3. from other market areas as long as there is enough capacity available

How Single Intraday Coupling works in detail

When a market participant submits an order for a different market area, it can be matched (i.e. met) as long as there is enough transmission capacity available. To match an order simply means that the market participant can meet and supply the energy demand.

Trade is done on a first-come-first-served principle where the highest buy price and the lowest sell price get served first.

Updating the SOB and CMM

When the order can be matched, the order matching is associated with implicit capacity allocation (this is when capacity and energy are priced together). While two orders are being matched, the SOB and CMM are updated immediately.

The update of the SOB means that the matched orders are removed from the SOB, and consequently the available transmission capacity in the CMM is updated. The number of borders that have their capacities updated depends on where the matched orders are located.

How data about trades is used

The Shipping Module (SM) receives data from the SOB about all trades when they are concluded. These can be:

  • between two different delivery areas, and
  • in the same delivery area between two different NEMOs.

The Shipping Module (SM) of the SIDC solution provides information from concluded trades to all relevant parties such as NEMOs and TSOs.

The data from the SOB and the CMM is enhanced with data from:

  • the relevant TSO,
  • the Central Counter Party (CCP), and
  • shipping agent data from the Shipping Module (SM).

This enhanced data is then sent to relevant parties such as the NEMOs and TSOs at the configured moments.

Market information

Products available

You can read what specific products are available in different market areas in the table below.

30-min products are currently tradable across the borders FR-DE, FR-BE and BE-NL.

15-min products are currently tradable across the borders BE-NL, BE-DE, NL-DE, AT-DE, AT-HU, AT-SI and HU-RO.

The availability of 15 minute products across other market areas will further expand in the future.

Number of trades per quarter

From mid-June 2018 to end of Q1 2022 151 million trades have occurred through SIDC.

PeriodNumber of trades
Mid-June to September 20183.5 million
October to December 20184.3 million
January to March 20194.8 million
April to June 20195.8 million
July to September 20195.6 million
October to December 20197.2 million
January to March 20208.3 million
April to June 20209.3 million
July to September 202010.8 million
October to December 202011.9 million
January to March 202112.7 million
April to June 202114.9 million
July to September 202115.4 million
October to December 202118.0 million
January to March 202218.5 million
April to June 202220.0 million

Stakeholder reports

To give stakeholders a comprehensive overview of the benefits SIDC delivers, the project has prepared reports featuring several indicators including amongst others traded volumes, average prices, cross-border capacity utilisation, share of cross-bidding zone trades in overall volumes and availability of the SIDC platform. These reports cover the operational period since beginning of January 2019.

  • For the period January 2019 until end of 2020 half-yearly reports are available.
  • As of April 2021 the reports are available on a monthly basis.
  • In the Q3/Q4 2020 report some indicators are calculated until end of March 2021.

2019 - Q1/Q2 report - Q3/Q4 report

2020 - Q1/Q2 report - Q3/Q4 report

2021 - April - May - June - July - August - September - October - November - December

2022 - January - February - March - April - May - June - July

Algorithm monitoring

Pursuant to Article 8 of Annex I of ACER decision 04/2020 on the Algorithm methodology, SIDC has developed algorithm monitoring reports, which will be generated on a monthly basis. These reports contain amongst others key indicators on the performance of the algorithm, prices, matched orders and volumes and the usage of SIDC products.

2021 - May - June - July - August - September - October - November - December

2022 - January - February - March - April - May - June - July

Future development

The development of SIDC is a priority to all parties (NEMOs and TSO) involved in the project.

Here we list future developments to expand and improve the efficiency of the SIDC.

  1. Plans are underway to integrate cross-zonal capacity pricing through intraday auction in line with ACER’s decision on establishing a single methodology for pricing intraday cross-zonal capacity.

  2. SIDC is working on the implementation of cross-product matching into the system. This will enable the matching of different products with one another (for example 15 min with 60 min orders).

  3. Plans are underway to implement the functionality to address losses on HVDC cables.

  4. SIDC has initiated the R&D phase for the implementation of flow-based allocation in continuous trading.

Resources Available

Steering Committee Minutes

Previous Steering Committee Minutes

Market Involvement

A User Group was convened with Market Parties (MPs) as an interface between the XBID Project and the Market. Following the successful XBID Go-Live it is agreed that the Market European Stakeholder Group (MESC) is the primary interface with MPs.

Previous Market Involvement documents

Press Releases

Previous Press Releases

Information notes


Intraday Operational Agreement

Publication of Intraday Operational Agreement according to article 20.7 of the Algorithm Methodology

According to article 20.7 of the Algorithm Methodology as approved by ACER all NEMOs shall in coordination with TSOs publish, by 1 September 2020, and then continuously update the relevant parts of the following documents:

  1. operational contracts;
  2. operational procedures;
  3. change control procedures;
  4. monitoring procedures;
  5. fallback procedures; and
  6. back-up procedures.

Based on this regulatory requirement SIDC parties publish these documents for transparency purposes. Any consultation or use of these documents is at your own risk and responsibility and the parties to the SIDC cooperation cannot be held liable for any damage incurred as a result of the use of these documents. Furthermore, these documents can only be used or quoted provided prior written consent is obtained of the parties to the SIDC cooperation. No rights or obligations can be derived from these documents. The publication of these documents does not affect any (intellectual) property right pertaining to these documents or to the information contained therein. The publication of these documents does not preclude the rights of the parties to the SIDC cooperation to amend, replace or suppress the documents.

Please note that for reasons of confidentiality certain parts of the content of the documents have been blackened out or have not been published (e.g. Exhibit 2, 13, 15 of the IDOA).

Intraday Operational Agreement (IDOA)
Exhibit 6: Operational Procedures
TSO Cooperation Agreement for Single Intraday coupling (TCID)
APPENDIX D - TSO operational procedures
GET THE MOST POWERFUL NEWSLETTER IN BRUSSELS