ELEXON Wider Access & TERRE Standalone Release update

There have been a number of updates and developments regarding Wider Access and TERRE.

Implementation dates*

ELEXON and NGESO have aligned the implementation of their changes to enable Wider Access (WA) to the GB Balancing Mechanism (BM) to take place on 11 December 2019. From this date the BM will be ready to receive independent aggregators as market participants, under the arrangements defined in Modification P344 and Change Proposal CP1517.

Market participants

We have five parties who have acceded to the BSC and three of them are actively going through the Qualification process to become a Virtual Lead Party. This means that no Secondary BM Units (SBMUs) are ready to participate from the industry Go-live scheduled for 11 December 2019. 

We are undergoing rigorous industry testing with an initial group of market participants as part of our Wider Access implementation preparations.


Update: Since this article was published the National Grid ESO’s Derogation request has been granted. 

We continue to await Ofgem’s decision on National Grid ESO’s Derogation request.

*Our projects are coordinated with National Grid ESO and all projects require changes to live systems.  Wider Access go-live dates are dependent on favourable operational conditions at the time to allow them to go into the production environment. There are contingency plans in place in the event that implementation is not possible on the intended dates.

Find out other information and updates regarding Wider Access and TERRE.


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