Project MARI Workgroups begin next week

Next week Elexon and National Grid ESO will begin the first Workgroups to develop changes to the Balancing and Settlement Code and the Grid Code to support Project MARI – a new European platform for providing balancing services.

What is Project MARI?

Project MARI (Manually Activated Reserve Initiative) is being developed as part of the European Balancing Guideline (EBGL). EB GL is European regulation for integration of balancing markets in Europe.

We have published a webinar to help Workgroup members get a quick understanding of Project MARI. 

The MARI balancing product

The EB GL requires transmission system operators (TSOs) to set up a platform for the exchange of balancing energy from manually activated frequency restoration reserves (mFRR) by July 2022. There are 25 participating TSOs so far.

The MARI solution will re-use systems and processes set up for Project TERRE where applicable, but MARI will be a balancing product in its own right (so it is not the same as TERRE). Important differences include that TERRE requires a response from market participants in 30 minute windows, whereas the window is 15 minutes for MARI.

Which market participants may be interested in MARI?

We expect that MARI could provide a new market for aggregators, storage owners, and demand-side response providers in GB to use. It could also encourage development of more renewable generation, which is important for meeting Britain’s net zero commitments. 

Developing the code change proposals

The first Workgroup will take place on Tuesday June 23, as the start of an eight month assessment procedure for the proposals to implement MARI. All Workgroups will take place remotely until further notice. The goal of the Workgroups is to develop a single change solution that can apply to both the Grid Code and the Balancing and Settlement Code.

Consultations on the proposals will take place in February and March 2021. The BSC and Grid Code Panels will make a recommendation to Ofgem on the proposals in March/April 2021, so that Ofgem can make a final decision.

Get involved

If you are interested and want to find out more, or you want to join the MARI Workgroups, please get in touch with us by emailing [email protected].


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