I wonder how efficiently a similar solar powered lift system would work for a "dirt battery"?
The *dirt battery I have in mind would be a vertical pulley system with small dirt scoops spaced at regular intervals. The scoops would pull dirt from the bottom of the pulley system and bring the material to the top were it is dumped into a mechanically locked, very large container. Over time the container would fill up, and when that stored energy is needed the container could be unlocked, at which point it would power a clockwork of turbines on its way down.
It’s less efficient than normal electric batteries and will take up far more space.
Gravitational storage only works in the very particular case of water, where moving it is downhill nearly perfectly efficient and free, and where you can also get free energy from things like rivers feeding in.
Yeah, now that you mention it I suspect that the mechanical stress upon a system that lifts dirt (as opposed to one that pumps water) would result in expensive routine maintenance, and possibly even catastrophe (i.e. the chain breaks).
ARES Nevada is developing a 50MW GravityLine merchant energy storage facility on approximately 20 acres at Gamebird Pit, a working gravel mine in Pahrump, Nevada. This project will employ a fleet of 210 mass cars, weighing a combined 75,000 tons, operating on a closed set of 10 multi-rail tracks.
It's not viable where water is a valuable resource.