Overview of the Trans European Replacement Reserve Exchange (TERRE)


This page gives an overview of TERRE which is a European project to implement a new Replacement Reserve (RR) balancing product.

GB participation in TERRE delayed until 2021

National Grid ESO (NGESO) have announced that it is now not possible to facilitate GB participation in the Replacement Reserve (RR) market for the Trans-European RR Exchange (TERRE) before the end of 2020.

Recent Modifications, Change Proposals and Issues

Industry testing

Elexon deployed the technical changes necessary to enable GB industry parties to join the central TERRE platform and trade in the European electricity market in May 2020.

This was followed by us supporting National Grid ESO and participants in joint ‘end to end’ (E2E) testing, with a first cycle in September and a second being completed successfully on 30 October 2020.

The testing of the E2E technical process of submitting RR bids through to dispatching instructions and provision of data for settlement was successful.

Future testing

There will be a re-test of the E2E process to validate that systems work as expected with the latest versions of software available. Recommencement of development and testing will be guided by the plans developed by the TERRE Implementation Group.

Leaving the European Union

The Trade and Cooperation Agreement between the EU and UK came into force on 1 January 2021. It was agreed on 24 December 2020 and published on 27 December 2020. We are still analysing the detail, and will update this page shortly.

‘Getting Ready for TERRE’ webinar

Elexon and National Grid ESO jointly hosted the ‘Getting Ready for TERRE’ webinar on 7 and 16 April 2020.

The sessions covered:

  • Pre-Qualification and how to participate and trade in the Replacement Reserves market
  • Data submissions
  • TERRE Settlement
  • Industry testing

You can see the slides from the webinar on NGESO’s website.

TERRE goes live in Europe

The central TERRE platform (known as LIBRA) went live on 6 January 2020. It was launched by Transmission System Operators (TSOs) from eight countries.

Countries will be joining in waves until 2021/22. Those participating include Great Britain through National Grid ESO, France through its transmission system operator RTE, as well as Portugal, Poland, Switzerland and Italy.


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