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 SEMOpx Rules and Procedures 


SEMOpx Rules and Glossary

After extensive consultation, primarily through the Business Liaison Group (BLG), the Commission for Energy Regulation (CER), in Ireland, and the Utility Regulator for Electricity Gas and Water in Northern Ireland (UREGNI), have each approved the SEMOpx Rules under the NEMO Conditions set out in the EirGrid and SONI Market Operator licences, respectively.  Letters of Approval of SEMOpx Rules were published on the CER and UREGNI websites on the 30th of June 2017:


The SEMOpx Rules and Glossary as approved by the regulatory authorities are as follows:


SEMOpx Operating Produres and Exchange Committee Procedures

The approved SEMOpx Operationg Procedures and SEMOpx Operating Procedures Glossary can be found here:

The final version of the SEMOpx Exchange Committe Procedures and SEMOpx Exchange Committee Membership Application and Undertaking can be found here:

As further detail on the specification of products and orders to be offered on the SEMOpx exchange becomes available from the PCR testing process, and confirmation is obtained from the Regional Coupling process on the Intraday Auction timings,  these procedures will continue to be finalised in consultation with the BLG or an alternative interim consultative forum that is to be established in accordance with section K.4 of the SEMOpx Rules.


SEMOpx Rules and Procedure Consultation Comments

During the BLG consultation process approximately 350 written comments were received as the SEMOpx Rules and Procedures were progressively developed.  A final spreadsheet containing all of the the non-confidential comments received and the SEMOpx project team’s responses is provided here:


SEMOpx Interim Consultative Committee

Prior to the establishment of the enduring SEMOpx Exchange Committee, any changes to the Rules or Procedures will be consulted on through the SEMOpx Interim Consultative Committee.

This Committee will meet on the following dates:

  • 13 February 2018
  • 14 March 2018

All market participants are invited to participate in these Committee meetings. To register for invitations and notifications for these meetings please register with the NEMO BLG mailing list or contact

The relevant documents for the process for changes to the Rules and Procedures are:


SEMOpx Modifications

Where modifications to the SEMOpx Rules or Operating Procedures is being proposed, a Modification Change Forms (MCF) will be prepared and made available. In addition comments received from Members and SEMOpx’s responses will be published.

The current MCFs are provided below:

Under Consultation

[Empty at present]

Pending Approval


Withdrawn or Rejected


Contact Details

Any queries in relation to the above information should be directed to

    SEMO is a joint venture between EirGrid PLC and SONI Limited