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Catching much rain very high up sounds stupid but at the same time that's something that needs considering. Stupid suggestions can be made un-stupid in my occas

Catching much rain very high up sounds stupid but at the same time that's something that needs considering. Stupid suggestions can be made un-stupid in my occasional experience. Could you elaborate please? Genuinely interested.

londons_explore 7y ago
[1] probably explains the downsides best (which I had not considered). I guess considering that, the only way to make it viable is if there isn't much rainfall, or if the terrain is very flat/porus, or if you can make the collection devices very cheap (for example a kite that flies into a cloud and can collect a few tens of liters per second 1km up could generate 100 kilowatts, which is a lot less than a big wind turbine, so needs to be a lot cheaper to compete) [1]: https://news.ycombinator.com/item?id=22994225 https://news.ycombinator.com/item?id=22994225
- throwaway_pdp09 7y ago
  Yeah, the effectiveness of wide area water collection is why your suggestion is 'stupid'. That's ok. Where it's possibly not stupid is in the comment you linked to "...as energy is linear with height" Sure potential energy is linear with height, but energy conversion efficiency is I think non-linear. You can I think collect more than 10x useful energy from an object that is 10x as hot. Equally I suspect you can get more than 10x useful energy from a column of water 10 miles high than from a column of water 1 mile high. I'm pretty sure your idea won't work but that doesn't mean it can't possibly work. It's more likely harvesting wind energy via kites (as has been proposed) is more realistic, but still, I don't like dismissing dumb ideas. Sometimes they can be made useful.
  - londons_explore 7y ago
    > Equally I suspect you can get more than 10x useful energy from a column of water 10 miles high than from a column of water 1 mile high. For a given flow rate, no. High pressure water can be fairly efficiently converted to electrical energy, which itself can fairly efficiently be converted between low voltage+high current to high voltage+low current. All the conversions are linear and well understood - there is no magic squared here to make this idea magic.
    - throwaway_pdp09 7y ago
      OK, you sound like an expert (not sarcasm) so if I may (and please note I never suggested a squaring relationship), > High pressure water can be fairly efficiently converted... And lower pressure less efficiently converted? Therefore the higher the column, the higher the pressure and the better the efficiency of the conversion?

londons_explore 7y ago

[1] probably explains the downsides best (which I had not considered). I guess considering that, the only way to make it viable is if there isn't much rainfall, or if the terrain is very flat/porus, or if you can make the collection devices very cheap (for example a kite that flies into a cloud and can collect a few tens of liters per second 1km up could generate 100 kilowatts, which is a lot less than a big wind turbine, so needs to be a lot cheaper to compete) [1]: https://news.ycombinator.com/item?id=22994225 https://news.ycombinator.com/item?id=22994225

throwaway_pdp09 7y ago
Yeah, the effectiveness of wide area water collection is why your suggestion is 'stupid'. That's ok. Where it's possibly not stupid is in the comment you linked to "...as energy is linear with height" Sure potential energy is linear with height, but energy conversion efficiency is I think non-linear. You can I think collect more than 10x useful energy from an object that is 10x as hot. Equally I suspect you can get more than 10x useful energy from a column of water 10 miles high than from a column of water 1 mile high. I'm pretty sure your idea won't work but that doesn't mean it can't possibly work. It's more likely harvesting wind energy via kites (as has been proposed) is more realistic, but still, I don't like dismissing dumb ideas. Sometimes they can be made useful.
- londons_explore 7y ago
  > Equally I suspect you can get more than 10x useful energy from a column of water 10 miles high than from a column of water 1 mile high. For a given flow rate, no. High pressure water can be fairly efficiently converted to electrical energy, which itself can fairly efficiently be converted between low voltage+high current to high voltage+low current. All the conversions are linear and well understood - there is no magic squared here to make this idea magic.
  - throwaway_pdp09 7y ago
    OK, you sound like an expert (not sarcasm) so if I may (and please note I never suggested a squaring relationship), > High pressure water can be fairly efficiently converted... And lower pressure less efficiently converted? Therefore the higher the column, the higher the pressure and the better the efficiency of the conversion?