In reply to Jed Rothwell's message of Fri, 31 Aug 2007 10:33:16 -0400: Hi, [snip] >I wrote: > >>This is interesting, but the discussion of a 10 megawatt Laddermill >>seems unrealistic. > >"Unrealistic" is the wrong word. No doubt there will be progress in >carbon filament cables. I guess I meant that this thing will require >the development of new technology, whereas the inventor seems to be >claiming that it could be implemented in the near future, even on the >megawatt scale.
Even a single kevlar cable traveling at 480 m /min (from your other post) with a cross section of 1 sq. in. and a tensile strength of 3 GPa, would generate almost 15.5 MW. However I suspect the design speed will be slower, and there are likely to be two cables, each of which could be thicker. At 1 sq. in. each and a density of 1.44 gm/mL, two 20 km cables would weigh 36000 kg. (20 km because the cable has to go up and also down in a ladder-mill. Actually they would need to be even longer, because they don't extend vertically, but at an angle. Anyone know how much lift one might expect? Regards, Robin van Spaandonk The shrub is a plant.
