National Grid ESO is set to debut a new fast frequency response service at 11pm tonight (1 October), using Dynamic Containment (DC) to boost the grid’s resilience.
Following an extensive consultation period, six tenders were received for the ESO’s new sub-second, post-fault response capability, from which two battery energy storage units were accepted in the first round.
These will provide 90MW of fast response services over 24 hours, with 165MW from six units available to compete in the day ahead tender for 2 October.
The ESO will now run tenders for DC seven days a week, procuring from 11pm to 11pm, in a move that will help to bring the frequency response market closer to real-time. This will give it an arrangement similar to one of National Grid ESO’s current frequency response auction trials, the operator said.
DC is designed to sit alongside the ESO’s existing frequency products, rather than replacing any for the moment. Initially there will be 500MW of low frequency response bought from providers, which will grow to 1GW next year and include high frequency response.
Ro Quinn, head of national control and chief engineer at National Grid ESO, said that the impact of the COVID-19 pandemic and the high renewable generation over the summer gave an “unprecedented insight into what operating a zero carbon electricity system with low inertia could look like".
“Although at times we needed to take more actions to make sure we kept the system secure, I’m proud that our control room proved equal to the engineering challenge.
“Dynamic Containment will be a game-changer. The boost the new service will bring to our frequency response capability will further strengthen the system and our ability to maintain a safe and secure electricity supply. It will also allow us to bring more renewable generation into the electricity mix, meaning more progress towards our zero carbon ambition.”
All technology types will be able to participate in the DC auctions, but battery storage is anticipated to make up the majority of providers in the early stage of the auctions while it is being further developed in conversation with industry.
DC is the first in a suite of new fast-acting frequency services National Grid ESO is looking to introduce to maintain the stability of the grid, keeping the system as close to 50Hz as possible.
This will include Dynamic Moderation and Dynamic Regulation, which will help complete the suite later on. Moderation is designed to manage sudden frequency imbalance in intermittent generation such as when there is gusting winds. Regulation will be able to manage small deviations when the frequency is close to 50Hz.
National Grid ESO highlighted that the need for rapid and real-time management of frequency was becoming increasingly import as more intermittent renewable generation comes onto the grid, with less inbuilt inertia.
In an effort to develop new forms of inertia, National Grid ESO signed contracts with five companies at the beginning of the year who are to provide inertia without the need to simultaneously provide generation. This led Drax Group’s Cruchan plant to start providing inertia in July, while Statkraft and Welsh Power are both installing new equipment to enable this service.
This formed the first phase of its Stability Pathfinder, with the operator now looking into a broader range of technologies as it moves into the second stage.
Kayte O’Neill, head of markets at National Grid ESO, welcomed tonight’s launch, saying they were “delighted” to be moving “frequency response procurement closer to real-time".
“It creates further opportunity for renewables to participate in frequency response markets, supporting our work to widen access and increase competition, and delivering better value for consumers.
“It’s another exciting step on our journey to a smarter and more flexible electricity system – and one which we can operate safely and securely with zero carbon by 2025.”