> Seems quite useless to me as the earth's gravitational field is not very strong.
Citation needed. The vast majority of current energy storage uses pumped hydro.
> Supposing that you could store the concrete blocks at a height of 50m (which is already a lot), you would need roughly 8000 tons to store 1 MWh. Taking account concrete density (2400kg/m^3), that's 19000 barrels !
Both the video and the article make it clear that the thing with the barrels is a 1/10th-scale prototype. The full-size version is slated to stand 120 meters tall and use 35-ton concrete blocks.
Citation needed. The vast majority of current energy storage uses pumped hydro.
> Supposing that you could store the concrete blocks at a height of 50m (which is already a lot), you would need roughly 8000 tons to store 1 MWh. Taking account concrete density (2400kg/m^3), that's 19000 barrels !
Both the video and the article make it clear that the thing with the barrels is a 1/10th-scale prototype. The full-size version is slated to stand 120 meters tall and use 35-ton concrete blocks.