Recent content by lfasn

Is it possible to construct elevators that can work for 2500 meters? Thus, in order to run a 1000 MWh generating plant, only 200,000 tonnes (i.e. 200 tons/MWh) of material would need to be moved every hour (assuming 70% efficiency ? -I wish others could confirm this or not, that is the only...

Isn't it true that water evaporates from the upper reservoir of pumped-hydro systems? Wouldn't these losses compare to the energy wasting system that would be required to spread the solid material? You would not really have to spread and collect the solid material horizontally. Lifting...

This idea is for an alternative to large scale energy storage. Sorry for the double and confusing post (https://www.physicsforums.com/showthread.php?t=179768), I should have posted here in the first place. As far as I can understand, pumped-storage hydroelectricity is the main technology used...

Thank you FredGarvin :) May be then.. would it possible to 'regenerate' most of the potential energy of the lifted freight, into electricity (e.g. with the same motor, only in reverse)? What could be the efficiency of this second step? If the round-trip efficiency could be more than 70%, then...

Hello all, I have probably a simple question for mechanical engineers. I would like to know the energy efficiency of real world freight elevators, going up with a speed of one meter per second. How about the best elevator's efficiency I could expect?