The Linked Service Windows feature aims to prevent the crossover problem that occurs at the boundaries of service windows and EFA blocks, where a change in summed power output can lead to a low- or high-frequency event.

NESO can decide to link together consecutive service windows for a given service. By doing so, NESO requests the same units to be selected for the same volume across those service windows for the concerned service to allow a smoother activation.

To achieve this result, if market participants wish to bid with a unit on a linked service window for the concerned service, they must submit baskets with the same unit on all the linked service windows. In addition, those baskets must be part of the same looped family and have the same volumes for the linked service, but prices can differ. For other services, market participants are free to bid different volumes.

For the selection of awarded baskets, EAC will ensure that baskets covering the linked service windows and belonging to the same looped family and unit are selected consistently. This means that all parent orders must be accepted together or not at all. The first child orders of each basket must be accepted at the same ratio, and the same goes for the second child orders, the third, and so on.

Information on linked service window activation and updates can be found on the EAC webpage .

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