There is a German company suggesting to cut a large piece of rock (think: hundreds of meters in diameter and depth) lose and lift that by pumping water beneath

There is a German company suggesting to cut a large piece of rock (think: hundreds of meters in diameter and depth) lose and lift that by pumping water beneath it. A moving mountain, it would be. Totally crazy stuff, I should check if that ever made any progress. Here is a German article about it. As far as I remember, the real issue is that pumps/generators with the required powers are very expensive. https://www.ingenieur.de/technik/fachbereiche/energie/lageenergie-ein-riesen-felsklotz-idealer-stromspeicher/ https://www.ingenieur.de/technik/fachbereiche/energie/lageen...