United Kingdom – Gravitricity will add hydrogen and heat storage to its underground gravity energy system.
The Edinburgh innovators have submitted a global patent to turn purpose-built shafts into pressurized energy stores, capable of safely accumulating significant quantities of the gas.
Martin Wright, company founder, said: “The gas grid of the future will be powered by intermittent renewables – and that means we need to find ways to store green hydrogen when energy is plentiful, close to where it’s required. Our idea is to make each Gravitricity shaft serve as a very large, sealed pressure vessel, and to use the shaft itself to hold significant quantities of gas. We believe this will be far more economic and safer than above-ground storage pressure vessels – and will massively increase the storage capacity of the system.”
A pilot Gravitricity hydrogen storage system, according to the company, might be operational in a few years. Gravitricity is now operating a 250kW demonstrator in Edinburgh and will begin work on their first 4-8MW project later this year.
The Gravitricity system suspends up to 12,000 tonnes of weight in a deep shaft via a series of cables, each of which is equipped with a winch capable of lifting its portion of the weight. Raising or reducing the weight absorbs or generates electrical power. Gravitricity has the ability to store extra energy and release it when needed – whether in short bursts or over a lengthy period of time. This can provide critical grid-balancing services on a local or national level, as well as behind-the-meter services in industrial use cases. Furthermore, the technology’s extended lifespan makes it a good fit for new grid infrastructure projects since it allows for a significant reduction in the materials needed to meet the appropriate peak power transmission capabilities.