https://www.youtube.com/watch?v=iGGOjD_OtAM https://www.youtube.com/watch?v=NIhCuzxNvv0 https://www.youtube.com/watch?v=XxGQgAr4OCo Softbank invested. What

https://www.youtube.com/watch?v=iGGOjD_OtAM https://www.youtube.com/watch?v=NIhCuzxNvv0 https://www.youtube.com/watch?v=XxGQgAr4OCo Softbank invested. What else do you need to know? By contrast, this is not stupid: https://gravitricity.com/going-underground-why-gravitricity-energy-storage-makes-sense/ They might still not execute well, but the idea is sound. What is different? They use a single weight, up to thousands of tons. It is suspended in a disused mineshaft, up to a kilometer deep, protected from weather. The one weight just goes up and down, i.e. it has just two moving parts, the weight and the winch. Winches are extra-mature technology. They are talking about sealing the shaft and compressing hydrogen into it. And, maybe storing heat there, besides. Both ideas are also simple, but they don't have to work for the product to be viable; if they do work, they add value. My impression is they added those so their solution could seem more "innovative": the weight in the shaft, by itself, is a sure thing, so probably missed out on some long-shot seed subsidies. Funding in the energy sector is not well aligned. They will probably need to figure ways to get their cost lower. Batteries are approaching $200/MWh, with people expecting that to hit $100. Certain chemistries ("Form") are quoting $20, but are probably over-optimistic. 50 years operation with no degradation could beat a nominally cheaper system that needs the expensive part replaced regularly.