Using stones to lift and store energy

A Danish innovation project called GridScale is exploring the use of heated basalt stones in steel tanks to store electricity from wind and solar sources as thermal energy. This is done by a system of compressors and turbines pumping heat energy from one or more storage tanks filled with cool stones to a corresponding number of storage tanks filled with hot stones. Scientists have discovered that certain stones, particularly quartz and piezoelectric materials, can convert mechanical pressure into electrical energy. This stored energy is released when rocks move from higher to lower elevations, such as during landslides or erosion.