National Grid ESO debuts Dynamic Containment frequency response service

National Grid Electricity System Operator (ESO) debuts its new fast frequency response service – Dynamic Containment – this evening, boosting its ability to respond rapidly to disturbances in the flow of energy around the grid.

Following an extensive consultation with industry, the ESO’s new sub-second, post-fault response capability will go live in the national control room at 11pm.

Six tenders have been received and two battery energy storage units accepted in the first round to provide 90MW of fast response services over 24 hours – with six units and 165MW available to compete in tomorrow’s day ahead tender.

Its soft launch will see the ESO running tenders for Dynamic Containment (DC) seven days a week, procuring from 11pm-11pm, moving the frequency response market closer to real-time in a similar arrangement to the model the ESO has been trialling through its frequency response auction trial.

Initially 500MW of low frequency response will be bought from providers, which is set to evolve to 1GW next year and to include high frequency response. All technology types can participate, with batteries anticipated to make up the majority of providers in the early phase while the service is being developed in conversation with industry.

DC will sit alongside the ESO’s existing frequency products for now, rather than replacing any.

The tool is the first in a suite of new fast-acting frequency services to be introduced by the ESO to maintain the system close to 50Hz – the frequency Britain’s grid must be kept at by balancing electricity supply and demand second by second.

Dynamic Containment is a game-changer. It will strengthen the system and help us to bring more renewable generation into the electricity mix, meaning more progress towards our zero carbon ambition

Dynamic Moderation and Dynamic Regulation products will complete the suite later, with the former designed to manage sudden frequency imbalances in intermittent generation (for example during gusting winds) and the latter to manage small deviations when frequency is close to 50Hz.

Rapid and real-time management of frequency is becoming increasingly important as the ESO operates a system with more renewable generation and less inbuilt inertia – inertia being a key influencing factor in how quickly frequency will change when there is a system imbalance.

The dynamic product suite’s frequency response capability will complement the ESO’s stability pathfinder initiative, which is already finding new ways to provide inertia without relying on it as a by-product of electricity generation through fossil fuel plants.

In July Drax Group’s Cruachan plant started providing inertia without generating power, while providers Statkraft and Welsh Power are installing new equipment at their Keith and Rassau sites respectively to provide grid stability services.

The introduction of DC marks a further development in the ESO’s operational capability, making the system more resilient to the low inertia conditions associated with a zero carbon grid.

Ro Quinn, head of national control and chief engineer at National Grid ESO, said:

“This summer gave us 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.”

Kayte O’Neill, head of markets at National Grid ESO, said:

“We’re delighted to be launching Dynamic Containment and 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.”