UK launches £28m ultra-long energy storage challenge

UK launches £28 million Ultra-Long Duration Energy Storage challenge

The UK Government has launched a £28 million Ultra-Long Duration Energy Storage Challenge to support technologies capable of supplying electricity for 100 hours or more.

EVCP Info 21 August 2026 2 min read Updated 25 August 2026

The programme covers electrochemical storage and underground hydrogen storage, with the aim of developing technologies that can store energy over periods far beyond conventional grid batteries.

First electrochemical competition offers up to £3 million

As part of the challenge, Innovate UK has opened a competition offering up to £3 million for project-development studies for electrochemical Ultra-LDES technologies.

Eligible technologies must be capable of at least 100 continuous hours of discharge and are expected to support planned UK demonstrator projects. A further phase of at least £10 million is planned for large-scale demonstrations.

Separate work under the challenge will support underground hydrogen storage.

This is not charger-side battery storage

Ultra-long duration storage operates on a very different timescale from batteries normally installed behind EV charging hubs or fleet depots. Those systems are generally used for short-term peak management, grid constraints or tariff optimisation rather than storing energy for several days.

The relevance to charging is further upstream. If longer-duration storage becomes commercially viable, it could help the wider electricity system manage periods of low renewable generation while large new loads, including high-power charging, continue to grow.

The launch also completes a wider £102 million set of Clean Energy challenges, including a £74 million Consumer-led Flexibility Challenge focused on shifting electricity demand as well as increasing storage.