London (CNN Business)In the Swiss municipality of Arbedo-Castione, a 70-meter crane stands tall. Six arms protrude from the top, hoisting giant blocks into the sky. But these aren’t building blocks, and the crane isn’t being used for construction.
The steel tower is a giant mechanical energy storage system, designed by American-Swiss startup Energy Vault, that relies on gravity and 35-ton bricks to store and release energy.
When power demand is low, the crane uses surplus electricity from the Swiss grid to raise the bricks and stack them at the top. When power demand rises, the bricks are lowered, releasing kinetic energy back to the grid.