The main purpose of the “footroom” service is to absorb excess wind generation which would otherwise have to be curtailed.
The Demand Turn Up (DTU) service sees providers paid to increase demand at transmission level, either by raising actual demand or by limiting generation which would otherwise offset demand.
As renewable generation grows, so does National Grid’s need for footroom. The system operator expects this requirement to be three to five gigawatts in 2017, although not all of this will need to be met with DTU.
The DTU service underwent a trial between May and October last year. National Grid says the service saw “significant utilisation” during July and August, with nearly 11 GWh of DTU being used over the summer.
The tender is open to any flexible technology which is not participating in the balancing mechanism. The entry threshold is 1MW, although sites of 0.1MW and larger can be aggregated.
The service will run throughout British Summer Time and will typically be called upon overnight and on weekend and bank holiday afternoons.
Applicants can bid to provide either ‘fixed’ or ‘flexible’ DTU. Those wishing to provide fixed DTU will need to and declare in which periods they will be available and submit availability and utilisation prices ahead of a tender in February. Successful applicants will receive availability payments even if the service goes unused.
Flexible DTU will be procured at short notice – twice each week throughout the duration of the service. Offers will be assessed on Fridays for the period until the following Monday, and on Tuesdays for the period until the following Thursday. Those which are unsuccessful will not receive availability payments but will still be eligible to receive utilisation payments if they respond to a call up.
The service will begin operating on 27 March. The deadline for fixed DTU submissions is 17 February.