Originally posted by twhitehead
But as I pointed out, the usual system for water, is pipes and generators. The whole bucket system is only necessary because of the change to gravel.
[b]Also, in our territory, if it were water, it would freeze in the winter here in Pa. The gravel idea would never have problems with freezing, unless the lube froze.
I don't know whether hydro elec ...[text shortened]... ith a cable for lifting. Far less moving parts, less wear and tear, less frictional losses etc.[/b]
I don't think there are any hydro dams in Pa, except maybe private small ones generating a few Kw.
Why do we need to lift weights at all? Why not just pump air into an underground sealed cave and use the pressurized air to run a turbine? The amount of moving parts goes down drastically, it can work even in Antarctica where the temperature gets cold enough to make dry ice snow.
It can work there because the building housing the parts can be insulated and heated with not a whole lot of energy needed. The better the insulation the less energy needed to keep things from freezing.
You would need to build a structure a kilometer high to get any kind of real energy storage, that alone would push the price in to the hundreds of millions of dollars if not more.
A hundred million bucks will buy a lot of lithium ion batteries!
BTW, here is a link to an article about tripling or more, the power density of Li Ion batteries using silicon as part of the anode. Silicon can absorb a lot of lithium but it expands to triple its size in doing so, and like water freezing in a bottle, can destroy the battery just as water freezing in a glass bottle will break the bottle when it expands.
They have found a way to control that expansion.
http://phys.org/news/2012-11-boost-silicon-based-batteries.html