The UK Government has launched the £28m Ultra-Long Duration Energy Storage (Ultra-LDES) Challenge, backed by UK Research and Innovation (UKRI), to accelerate the development of technologies capable of storing electricity for at least 100 hours. The programme will support projects spanning advanced battery technologies and underground hydrogen storage, with funding aimed at UK innovators developing systems that can hold clean electricity for four days or more before releasing it to the grid. UKRI has also opened a separate competition offering up to £3m for feasibility studies into electrochemical Ultra-LDES technologies, helping promising concepts move closer to commercial deployment. The result could be a more flexible and resilient electricity system, with greater capacity to store surplus renewable power and use it when wind and solar generation falls. By reducing the need to turn to gas-fired generation during periods of low renewable output, the programme could strengthen UK energy security, limit exposure to volatile fuel prices and support the transition to a low-carbon grid. Speaking on the investment, Minister Michael Shanks said: “Homegrown clean energy is our …