National Grid’s Distribution System Operator (DSO) has announced the successful awarding of 196GWh of flexibility availability through its most recent annual tender, marking its largest long-term flexibility portfolio to date. This initiative expands the DSO’s contracted volume of flexibility, a critical component in managing constraints on the distribution network, particularly as the electrification of energy systems accelerates and more renewable generation connects at a local level.
Cathy McClay, Managing Director of National Grid DSO, remarked on the tender’s success, highlighting the growing momentum behind flexibility as an efficient strategy for operating the electricity network and reducing costs for consumers. McClay stated, “We’re delighted to have delivered our largest long-term tender yet and to see such a positive response to our new Flex Up service. It’s a strong foundation as we continue to expand and evolve our local flexibility markets.”
The 2025 tender round introduced broader availability windows and increased service hours, thus expanding participation opportunities. National Grid DSO noted that more than 4.5 million customers are located within flexibility zones, widening the potential pool of flexibility providers, which now range from large assets to smaller distributed technologies aggregated across multiple sites.
A detailed analysis of the published trade results shows that a significant portion of the awarded ‘availability’ volume—around 143GWh—comes from high-voltage products that combine scheduled availability with day-ahead operational utilisation. Additionally, 52.6GWh is associated with ‘DTU/GTD only’ variants, aligning with the DSO’s statement that its new demand turn-up service, FlexUp, awarded 52GWh across 23 high-voltage zones.
The awarded portfolio indicates an increasing reliance on flexible, low-carbon demand. Electric vehicle charge points constitute the largest single category by awarded availability volume, followed by broader site demand flexibility, solar, and storage. Fossil gas assets are also included but represent a smaller portion compared to EV charging and other low-carbon categories, underscoring the shift towards electrified loads and distributed resources rather than conventional plants.
National Grid DSO also emphasised that further opportunities exist in the short-term market, which is shifting from a week-ahead to a day-ahead procurement model. This transition aims to align flexibility purchasing more closely with real-time network conditions, facilitating easier matching of local constraints with assets capable of responding at shorter notice.
