Interesting thread . I think most are getting a bit carried away without having all the details . It would be good to get some information on these proposed pumped hydro systems .
The Kalgoorlie one is interesting . No doubt there's plenty of elevation but that's only part of the solution unfortunately .
Using the Kidstone mine project as a reference might be helpful .
I'm not familiar with the Kalgoolrie area . The first question is the location of the upper dam . It's a bit hard to tell but are there any storages in that area for the upper dam ? Digging a new one wouldn't be feasible I wouldn't have thought so unless there's another part of the mine to use as the upper storage I'm not sure how this would work ?
Evaporation could be an issue although that can be controlled . On the plus side having a very large solar farm adjacent to the pit is a real possibilty and given Kal's weather , that would probably work well .
Given the size of Kal I don' think they would have much trouble selling the power .