A global energy transition is expected to increase the share of renewable energy from current 12% to 90% in 2050. Different from the on-demand fossil fuel, inteminent renewable energy including solar and wind calls for large-scale, cost-effective grid-scale energy storage facilities. Currently, the energy storage is dominated by gravity-based pumped hydro (90%), followed by lithium, lead and zinc batteries (5%), and then the rest. Recently, a Swiss company Energy Vault demonstrated potential to change this framework by the use of cranes to lift and lower heavy composite blocks into massive architectures, which delivers gigawatts capacity and remarkable energy efficiency of 83-85%. See full story at Advanced Science News.