National Grid expects to have to manage excess generation of 3-5GW during the summer of 2017 and has announced plans to procure more so-called ‘footroom’ services to soak up the power overspill.
Services will include a major expansion of ‘Demand Turn-Up’, a product offered for the first time as a pilot scheme in 2016, in which customers are paid to increase their power use. Last year National Grid contracted for 309MW of such capacity and called on providers 323 times. It extended the pilot programme by a month, from September to October, to manage a system issue. It suggested in a review of the year that utilisation might have been higher, if it were not for “below average illumination” reducing solar PV production.
In 2017 National Grid will be seeking Demand Turn-Up for the whole period of British Summer Time, from 27 March to 28 October. It will offer payments when it calls on companies to turn up demand overnight and at weekends when usage would otherwise be too low – 23.30-8.30 and 13.00-16.00 in March, April, May, September and October, and slightly extended overnight (23.30 -9.00) in June, July and August.
Once they have signed a framework agreement – which must be signed by 17 February – companies will be able to offer either or both of availability for the entire period (in a tender to be opened in February), and flexible availability in response to a process in which National Grid will assess its requirements twice-weekly during the Demand Turn-Up period.
The System Operator has responded to feedback from the experience of 2016 by: reducing the minimum volumes of Turn-Up to be offered; allowing aggregators to deliver it from more, smaller sites; allowing multiple bids to be made for offer periods; and removing geographical restrictions on the sites involved. It also said that, “Unlike 2016, providers will have the flexibility to submit their own prices for the service – these prices will inform the economic assessment to determine which parties are accepted.”
Alternative ‘footroom’ actions include holding back hydro generation, exporting via interconnectors, and contracting with inflexible generators to reduce their power production.
Fast Frequency Response
The System Operator has also expanded other system operability services. That includes the opportunity to provide Fast Frequency Response (FFR), which calls for responses in around a second to increase power provided to the system, hoping to bring in more and smaller providers. Previously, National Grid contracted for FFR in tranches of 10MW but it has acknowledged that this threshold is “the biggest challenge for new entrants”. From 1 April it will contract for as little as 1MW. It will also allow providers to add extra volume to existing contracts from 1 April i.
The FFR service is an important opportunity for batteries, which can respond at the fast timescales required. National Grid is working on other changes that will help new providers enter into contracts.
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