Swiss startup Energy Vault wants to overcome the limitations of lithium-ion batteries by storing green wind and solar energy by stacking massive towers made up of 35-ton bricks, The Wall Street Journal reports.
In August, the startup locked down $110 million from SoftBank’s Vision Fund. The company already constructed a 400-foot demonstration tower and is planning to eventually build cranes up to 500 feet in height.
A pre-programmed crane on top of a massive tower lifts and stacks colossal bricks on top of each using excess power from wind and solar plants. When demand exceeds electricity production, the crane reverses the process, recouping energy by unstacking the tower of bricks.
Just 20 cranes could provide enough power for 40,000 households over a 24 hour period, according to the WSJ.
Lithium-ion batteries rely on rare-Earth metals, the extraction of which is steeped in environmental and humanitarian problems, and tend to lose their capacity over time.