4 ms·

I'll just put this here http://what-if.xkcd.com/23/ http://what-if.xkcd.com/23/

• gus_massa 12y ago
  I agree. It's interesting to see a back of the envelope calculation to prove that the idea is not applicable. Another interesting calculation would be how this method compares to other electricity generation devices for isolated places, for example solar panels or wind turbines.
  • maxerickson 12y ago
    The What If link addresses the overall utility of using such a short drop for generating electricity -- the interesting part of the calculation is that over a year you get a trivial amount of power per unit of surface, ~8 kw-h off of 140 square meters. Compare to solar which generates several hundred kw-h over a year for each square meter. A small wind turbine should also easily beat the 8 kw-h (it only has to average 1 watt of output). Those systems will cost more than some little gadget that gets stuck under a downspout, but they provide a great deal more return.