Is a 500m-1500m shaft is pretty much going to fill with water? I could see a well designed weight being able to work in water (although water turbulence would e

Is a 500m-1500m shaft is pretty much going to fill with water? I could see a well designed weight being able to work in water (although water turbulence would erode the shaft walls. I don't see how air compression would solve this. The principle however of storing energy by raising a weight could also be used anywhere with a steep enough hill/cliff/montain and the weight could in theory be on a rail not just suspended. Efficiency would potentially not be on par, however linked into solar/wind systems this is less about efficiency and more about creating a 1MW long term battery with a lifetime of 50+ years. Guessing cost of digging and maintaining a hole compared to installing a guide rail is significantly higher.