Since 1 June 2021, RTE has published detailed information on the margins and forecast values of the power system imbalance, which are essential components of the security of the supply-demand balance.

This new publication is available on the Service Portal as well as via API on the Data Portal. It presents throughout the day:

• The forecast imbalance for France;
• The margins required at 1% risk, reflecting uncertainties likely to affect the supply-demand balance, such as forecasting errors on consumption or renewable energy, unforeseen events affecting power generation sources, delays in the start-up of groups etc.;
• The available margins, representing the volume of power that can be dispatched by RTE to manage system balancing and to deal with potential contingencies. The available margins consist of normal bids submitted by the market participants on the balancing mechanism; additional bids from the balancing mechanism; and inter-TSO backup contracts.

This publication thus gives an overview of the forecast tension on the balance of the electrical system: when the operating margins (sum of the margins available on the normal bids and the forecast imbalance) are lower than the required margins, RTE may call for additional bids or backup bids.

In these situations, RTE then acts on the system, for example by carrying out actions to reconstitute margins (by sending balancing orders on the balancing mechanism) or by sending messages to the balance responsible parties and balancing service providers, to inform them of the system imbalance and the potential activation of additional bids (see the tab Summary of messages concerning lack of bids).

This overview of margins and imbalance is available from the evening of D-1, and is updated once an hour, incorporating the latest assumptions available.

July 12, 2021