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 SEMOpx Registration 



SEMOpx operate a Day Ahead and Intraday Market for the SEM. The Day Ahead and Intraday Markets allow suppliers and generators to contract for physical delivery and minimise their exposure in Imbalance Pricing.

The Day Ahead and Intraday Markets are coupled with other European markets to maximise efficient cross zonal trade.


Participation in the Day Ahead and Intraday Markets is not mandatory, but provides firm contracted quantities and prices for Suppliers and Generators.

Registration Forms

Existing SEM Participants and new SEM Participants that are looking to be involved in the I-SEM Market Trial will need to complete the SEMOpx Transitional Registration Forms. Otherwise please complete the standard SEMOpx registration forms.

A SEMOpx registration guide is included with the registration packs and will provide an explanation for each form, its significance, the submission format required, and a due date for each returned form.  Please refer to the relevant registration guides with initial queries.

Information is also included in the registration guide regarding registration with ECC who provide the clearing and settlement services for the SEMOpx Day Ahead and Intraday Markets.


Important! Participants are strongly encouraged to submit their applications as early as possible. In particular, registration for the DAM and IDM involves meeting ECC “Know Your Customer requirements” and contracting a Clearing Member/Settlement Bank which can take a number of months to complete


SEMO is a joint venture between EirGrid PLC and SONI Limited