Gravitricity and VSL explore underground green hydrogen storage

In order to investigate purpose-built underground green hydrogen storage, energy storage company Gravitricity and infrastructure provider VSL Systems UK have signed a memorandum of understanding (MoU).

The method utilized by Gravitricity’s energy storage system involves raising weights in a deep shaft (the company specifically targets abandoned mining shafts) and releasing them when energy is needed.

This new alliance expands the possibility of storing green hydrogen at these locations as well, advancing the hydrogen economy in the UK and bolstering the required storage.

The FlexiStore solution from Gravitricity may offer a substitute for subsurface salt caverns in terms of large-scale hydrogen storage, according to the company, which claims that it is more adaptable.

In 2021, the company, expanding on its prior gravity storage method, submitted a patent for turning its purpose-built shafts into pressurized energy reservoirs for both hydrogen and heat storage.

Each rock shaft inside FlexiStore would be six meters in diameter, 365 meters deep, and steel lined. Up to 100 tonnes of green hydrogen could be stored in a single location.

One or more FlexiStores could be erected next to green hydrogen production facilities that use renewable energy, promoting the growth of hydrogen-powered commercial filling stations and industrial hubs. By lowering transportation expenses, this might lower the cost of green hydrogen.

For the UK to achieve its net zero goals by 2050, a major change might be needed to increase the hydrogen industry and its storage capacity.

It is anticipated that electricity alone won’t be sufficient to decarbonize some industries. This category includes challenging industries including heavy industrial, steel production, transportation, and heating, among others. A more promising technology that makes it possible to decarbonize these industries affordably is green hydrogen.

For the UK pilot project, Gravitricity has selected a number of sites, and it is currently in talks with site owners, including utilities, about the test project and upcoming commercial initiatives. The two businesses are currently looking for funding to start the first large-scale demonstrator project in the UK. Once this is finished, they intend to roll out green hydrogen FlexiStores across the country.

This comes after Gravitricity successfully operated a 250kW prototype in Edinburgh in 2021, demonstrating the viability of the revolutionary technology. Following this, it obtained project support for its intentions to construct a full scale 4–8MW facility in an abandoned mine shaft in 2022, led by the European Investment Bank.