Yes this principle makes perfect sense of course. The energy creating the extra power actually comes from the excavator loading the ore. Unfortunately the Oz mines are in reverse. ie loaded up hill empty down hill. Also the illistrated example is of course is about half of the mass of the 797 I illustrated so it is no where applicable but it is slowly getting there. If you have been to wales you may have travelled up the side of a mountain there at the alternative energy research place in a fernicular powered by water and passengers in exactly the same way, ie the heavy load of pasengers is used to pump the water back up the top to use its weight to pull the empty or not second funicular back to the top. There is also one at como in Italy which uses two funiculars in conjunction with water to achieve the same result. My point was and is that banning all ice vehicle by 2035 is bollocks.
