National Gas receives funding to develop Gravitricity underground hydrogen storage system

Developed by Edinburgh energy storage specialist Gravitricity,  the so-called H₂FlexiStore system uses purpose built lined geological shafts to store up to 100 tonnes of pressurised hydrogen at 200 bar per shaft, equivalent to 3.3GWh of raw energy (enough to drive 10,000,000 miles in a hydrogen fuel cell car).

Although the UK does have a limited number of underground salt caverns suitable for hydrogen storage, they only exist in very specific locations, which don’t always match up with where current or future storage demands will be situated. Gravitricity claims that one of the key advantages of its system is that it can be sited in a wide range of geological conditions, and meet the requirement to safely and securely store large amounts of hydrogen close to demand.

The Ofgem funding follows on from a successful 2024 feasibility study which concluded that strategically located nodal storage can improve the resilience and operational efficiency of a hydrogen gas network.  It will enable a consortium - which also includes 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 next year.