, called GraviStore, uses heavy weights – totalling up to 12,000 tonnes – suspended in a deep shaft by cables attached to winches. When there is excess electricity, for example on a windy day, the weight is winched to the top of the shaft ready to generate power.
Among the company’s clients are the Velenje coal mine in northeastern Slovenia, which is owned and operated by government-owned Premogovnik Velenje; First Quantum Mineral’s– Europe’s deepest zinc and copper mine – in central Finland; the former Darkov mine in the Czech Republic, which is being decommissioned by DIAMO, the Czech state enterprise in charge of mitigating the consequences of uranium ore and coal mining; and the Geiger Group’s Grube Teutschenthal mine near Halle, central Germany.
Wright pointed out that Gravitricity has already demonstrated its GraviStore technology with an above-ground 250kW demonstrator, where the company successfully raised and lowered two 25-tonne weights to generate full power and verify the system’s speed of response.