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EUPHEMIA is the day ahead pricing algorithm currently in use throughout Europe. It was developed by the Price Coupling of Regions (PCR) initiative, an organisation of European power exchanges. Further details on the EUPHEMIA algorithm are available here.

What is the I-SEM Trialling of EUPHEMIA?

The use of EUPHEMIA for the day-ahead market in the Integrated Single Electricity Market (I-SEM) is outlined in the SEM Regulatory Authorities’ (RAs) high level design (HLD) for the I-SEM. As such, the ability of I-SEM participants to successfully represent their trading requirements through EUPHEMIA will be explored to ensure adequate understanding of the algorithm and how it can be used in the I-SEM to allow for efficient participation in the market.

SEMO, in its role as the market operator for the SEM, member of EUROPEX and associate member of PCR, has been asked by the SEM RAs to progress this trialling.

Objectives of the Trials

EUPHEMIA allows for the use of a number of different bid and offer, collectively order, types. Each of these order types has distinct characteristics in their representation of participants’ commercial and technical data. The objective of the I-SEM trialling of EUPHEMIA is to explore the use of these order types to create SEM representative market orders and to analyse the resultant outputs. This will assist in developing participants’ and SEMO’s understanding of the EUPHEMIA algorithm.

Process of the Trials

In March 2015, SEMO published a high level plan of the I-SEM EUPHEMIA trials. This plan set out that the trials would be split into two categories, as follows:

    1. Initial Phase – internal to SEMO only, scheduled to end May 2015; and,

    2. Commercial Phase – performed by SEMO in conjunction with industry, scheduled to end December 2015.

Full details of the plan may be viewed here.

The Initial Phase report outlines the assumptions, methods and findings of the Initial Phase. The report is available here. 

Industry Working Group

To manage industry interactions, and allow for industry feedback, SEMO formed an I-SEM EUPHEMIA working group in April 2015. This working group will be the primary method of communication and interaction between SEMO and industry throughout the I-SEM EUPHEMIA trials.

The terms of reference for the working group may be viewed

The industry working group members list may be viewed here.

Information on the preparation of initial test case Participant data may be viewed here.

More Information

Any queries in relation to the I-SEM trialling of EUPHEMIA should be directed to







SEMO is a joint venture between EirGrid PLC and SONI Limited