There has been new progress in gravity storage for Australia. Startup Green Gravity, having partnered up with abandoned mines, now signed with engineering company GHD, and is likely to provide a prolonged period of energy storage for the power grid through moving heavy objects vertically that would capture and release gravitational kinetic energy.
Gravity storage is similar to that of pumped-storage hydroelectricity in concept, but the medium of gravity that is water has been replaced by heavy objects, and stores electricity through reallocating the position of heavy objects. Heavy objects are transferred to a power storage tank at a higher latitude when there is excessive production of power, while an elevation in power demand would prompt a release of the heavy object, before sending it back to its original position that would propel power generation from the turbine.
Green Gravity hopes to store and generate power by pulling up and lowering heavy objects left behind in abandoned mines, where power cables that carry the heavy objects would pass through the winder device when descending, before initiating the power generator.
Green Gravity and GHD will unfold a partnership in technical engineering, policies, regulation management, and accomplishment of grid connection in the future. Mark Swinnerton, CEO of Green Gravity, commented that this partnership symbolizes the next key step in commercialization for local gravity storage technology.
Swinnerton also added that it is exceedingly important to commercialize new technology as proven by the constantly surging electricity tariffs recently, and that a solution would depend on the collaboration, innovation, and determination between different divisions.
Green Gravity currently aims to elevate heavy objects when there is an excessive level of renewable energy, and vice versa when the demand for electricity rises. Despite similarities in Green Gravity’s technology compared to other gravity storage, Swinnerton believes that the company’s advantage lies on the utilization of abandoned mines instead of constructing additional towers.
Australia is rich in experience and history of mining, and currently has more than 85K abandoned mines. Green Gravity, prior to signing an agreement with GHD, had also announced to be working with Australian coal mining companies on exploring potential applications for the Austar coal mine in New South Wales. Swinnerton commented that the technology of Green Gravity may be applied on the ventilation shafts of 400-500m decommissioned tunnels that are used to connect underground mines and the surface.
Green Gravity currently has about 20 candidate shafts located at Illawarra and Hunter Valley in New South Wales, as well as Mount Isa of Queensland, and Tasmania. The pilot study on Austar is expected to complete in 2023.
(Cover photo source: Green Gravity)