About Gravity Storage
Gravity Storage is a concept with which unprecedentedly large quantities of power can be stored for a long time of 6-14 hours, and can be made available again. The fundamental principle is based on the hydraulic lifting of a large rock mass. Using electrical pumps, as already used today in pumped storage power plants, water is pumped beneath a movable rock piston, thereby lifting the rock mass. During times of insufficient generation of renewable power, the water which is under high pressure from the rock mass, is routed to a turbine, as in conventional hydroelectric plants, and generates electricity using a generator.
The capacity of energy storage can be choosen between 1 and 10 GWh, comparable to large Pumped Hydro Storage.
The rock piston should have a diameter of at least 100 meters/ 300 ft. in order to be competitive with other bulk storage solutions. The Levelized Costs of Storage (LCOS) vary between 0,09 and 0,18 $ per kWh. Investment costs vary between 120 and 380 USD per installed kWh.