The UK battery energy storage market is experiencing significant investment and revenue stack evolution in 2026. Long-duration energy storage startups are securing substantial funding to address grid instability, while established funds report strong revenue growth. Furthermore, new government cap and floor schemes are providing crucial revenue certainty for large-scale lithium-ion and flow battery projects across the nation.
Long-Duration Storage Funding
Certain Energy has raised 10 million pounds in Series A funding to commercialise its manganese flow battery technology. The round was led by the British Business Bank, with participation from Centrica Energy and Ceres Power. This investment targets the growing need for long-duration energy storage to manage grid instability and reduce the billions spent annually on renewable curtailment.
Fund Revenues And Growth
Gresham House Energy Storage Fund reported strong financial progress in the first half of 2026, with portfolio revenues reaching £34.7 million. This figure represents a significant increase from the previous year, supported by higher earnings and double-digit EBITDA growth. The company also successfully completed a trial of its alternative revenue strategy.
Government Revenue Support Schemes
The UK regulator Ofgem has provisionally selected several battery projects for its long-duration energy storage cap and floor scheme. This initiative provides a guaranteed revenue floor to support investment, requiring owners to repay revenues exceeding an agreed price cap. Projects like the Rigifa battery in Scotland and the Ocker Hill site are set to benefit from this twenty-five-year support mechanism.
Key Takeaways
Certain Energy secured 10 million pounds to develop manganese flow batteries for grid-scale deployment.
Gresham House Energy Storage Fund generated £34.7 million in revenues during the first half of 2026.
Ofgem selected sixteen projects for its long-duration energy storage cap and floor scheme to provide revenue certainty.
The Scottish Rigifa project secured planning consent as a 200 megawatt 18-hour battery storage system.
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