Gravitricity, VSL study UK’s underground green hydrogen storage


United Kingdom – Energy storage startup Gravitricity and infrastructure supplier VSL Systems UK have signed a cooperation agreement to explore purpose-built underground green hydrogen storage.

The energy storage device used by Gravitricity works by elevating weights in a deep shaft and releasing them when energy is required. The hydrogen economy in the UK is advanced, and the necessary storage is strengthened, thanks to this new alliance, which also increases the possibilities of storing green hydrogen at these places.

In terms of large-scale hydrogen storage, Gravitricity’s FlexiStore system may potentially replace subterranean salt caverns since it is more versatile, the business believes. The business applied for a patent in 2021 to convert its purpose-built shafts into pressurized energy reservoirs for both hydrogen and heat storage, building on its earlier gravity storage technique.

The diameter and depth of each rock shaft inside FlexiStore would be six meters, 365 meters, and steel lined. Green hydrogen might be kept in one place for up to 100 tonnes. The development of hydrogen-powered commercial filling stations and industrial hubs could be facilitated by the construction of one or more FlexiStores near to green hydrogen producing facilities that utilize renewable energy. This could bring down the price of green hydrogen by reducing transportation costs.

Capacity shift

A significant shift in the hydrogen industry and its storage capacity might be required for the UK to meet its net zero ambitions by 2050.

It is projected that some businesses won’t be able to reduce their carbon footprint using just power. This group of difficult industries comprises, among others, heavy industry, the manufacture of steel, transportation, and heating. Green hydrogen is a more promising technology that enables the cost-effective decarbonization of various industries.

Gravitricity has chosen a number of sites for the UK pilot project and is already in discussions with site owners, including utilities, about the test project and forthcoming business endeavors. To launch the first significant demonstrator project in the UK, the two businesses are presently seeking finance. After this is done, they want to open green hydrogen FlexiStores all across the nation.

This follows the successful operation of a 250kW prototype by Gravitricity in Edinburgh in 2021, proving the practicality of the ground-breaking technology. Then, with the help of the European Investment Bank, it was able to get project funding for its plans to build a full-scale 4–8MW facility in an abandoned mine shaft in 2022.