© Supplied by Gravitricity National Gas has received £500,000 of Ofgem funding to develop underground hydrogen storage technology from Edinburgh-based Gravitricity.
The company’s H2FlexiStore will use purpose-built underground shafts to store up to 100 tonnes of green hydrogen.
The two commonly proposed storage systems for hydrogen are above-ground tanks or subterranean salt caverns. However, above-ground solutions are limited in size, while salt caverns are restricted to areas with favourable geography.
Gravitricity’s H2FlexiStore aims to offer a middle ground by boring shafts six metres wide and 365m deep lined with steel, close to industrial users of hydrogen.
The Ofgem funding will enable a consortium, made up of Southern Gas Networks, Guidehouse, Edinburgh University, Energy Reform and Premtech, to design and model a working system over the next six months, ahead of a potential demonstration phase in 2026.
Gravitricity co-founder and executive chairman Martin Wright said: “Given the strategic need for grid-scale energy storage both nationally and internationally, it is crucial that enabling hydrogen storage technologies such as H2FlexiStore are commercially mature in time to offer cost-effective resilience within current and future energy systems.
© Supplied by Gravitricity“This support from Ofgem enables us to prepare both technically and commercially for the delivery of a demonstration project next year and the early commercial projects within our existing pipeline of opportunities.”
Hydrogen storage
Gravitricity has been developing its plan to store hydrogen underground for years, having signed a deal with VSL Systems UK in 2023 to help design the necessary infrastructure.
The company also brought in Gneiss Energy that year to help raise £40 million of funding to build three energy storage demonstrator projects in the next five years.
The new funding comes from Ofgem’s Strategic Innovation Fund and follows the successful completion of a National Gas led feasibility study in 2024, which identified H2FlexiStore as the preferred technology to provide locationally flexible hydrogen storage.
National Gas previously launched Project Union, which is exploring how to create a UK hydrogen backbone to transport 100% hydrogen and connect hydrogen production and storage with industrial end users across Britain.
Once the design project is successfully completed, a third and final project phase could be secured, which would see the delivery of a technical demonstration project supported by multi-million pound funding from the Strategic Innovation Fund.
National Gas innovation analyst Kelvin Shillinglaw added: “This project is a critical step forward in ensuring the UK’s gas networks are ready for a hydrogen-powered future.
“By embedding resilience with operational hydrogen storage directly into the transmission system, we can maintain operational flexibility, reduce costs for consumers, and support the decarbonisation of heat and power.”
