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Your comparison to a space elevator is pretty disingenuous. We have planes that run on energy beaming down from space. Solar impulse 2 worked. Month-long endur

Your comparison to a space elevator is pretty disingenuous. We have planes that run on energy beaming down from space. Solar impulse 2 worked. Month-long endurance solar drones have existed for a year or two. Payload sucks, and wingspan is long, but that doesn't change the fact they work. We have battery powered planes. The tech is superior to ICE in every way but carrying enough energy to fly long distance (which is the deal breaker). Solar alone is insufficient due to energy density and efficiency, but a few kw per m^2 would work. A 2kW/m^2 monochromatic light would solve both of these. Existing PV tech is about 80-90% efficient at its bandgap. Epoxy some standard quarter cells into the top of an airbus, shine a 1000nm laser a few times as bright as the sun on it and your "complex" receiver is done. Nothing needs inventing to make it work. The batteries can provide a safe abort in anything except a transpacific route. Will it beat syn fuel economically? Almost certainly not. But there are no completely out there engineering challenges involved. Just a similar level of engineering to any new airframe.

throwanem 4y ago
> shine a 1000nm laser a few times as bright as the sun on it I saw you palm that card.
- Schroedingersat 4y ago
  This was the proposal to begin with. Nothing is being hidden. Or did you think that a 1-10kW/m^2 beam didn't involve a 1-10kW/m^2 beam for some reason?
  - throwanem 4y ago
    No, but I think there's a reason you aren't touching at all upon the mechanics of its generation or direction. Given that even under absurdly generous assumptions you need around five square kilometers, or about 2 ISS' worth, of solar panel area per beam, this omission is not surprising.
    - Schroedingersat 4y ago
      Again, this was the entire premise. The receiver was cited as being the impossible part. I was pointing out the flaws in that argument, not claiming the entire concept was economic. By turning around and crying that I didn't say something unrelated you're being completely disingenuous.
      - throwanem 4y ago
        You made an argument that sounds like it was meant in support of the concept and I responded to it as such. It sounds like you're now saying you meant it to read as something akin to sarcasm, which is fair as far as it goes, but it is a bit rich in that case to call me disingenuous for responding in earnest to disingenuity too deeply buried or poorly executed or both for me to recognize.
        Schroedingersat 4y ago
        Yet again, you raised the base premise as if it were some sneaky hidden thing and made the first accusation. Now you're trying to rewrite the entire conversation so that it was somehow relevant or productive. This on top of me explicitly saying the economics of the problem are probably terrible. Only an idiot or someone acting in bad faith or both would say "Aha! You need a beam with n megawatts to receive a beam with n megawatts!" Of course you do. That same solar array exists in the syn fuel scenario too (except 3-10x bigger and on the ground). Raising it as if you found a gotchya is not just disingenuous but also incredibly stupid.
        throwanem 4y ago
        I'm having a pointless argument with someone a billion subthreads deep on Hacker News. Of course it's neither relevant not productive. Stupid I'll grant you, but I've had an annoying morning and this is apparently how I'm choosing to waste a few minutes before I go on to the next thing. Presumably I'm getting something out of it, but God alone knows what. So it goes.

throwanem 4y ago

> shine a 1000nm laser a few times as bright as the sun on it I saw you palm that card.

Schroedingersat 4y ago
This was the proposal to begin with. Nothing is being hidden. Or did you think that a 1-10kW/m^2 beam didn't involve a 1-10kW/m^2 beam for some reason?
- throwanem 4y ago
  No, but I think there's a reason you aren't touching at all upon the mechanics of its generation or direction. Given that even under absurdly generous assumptions you need around five square kilometers, or about 2 ISS' worth, of solar panel area per beam, this omission is not surprising.
  - Schroedingersat 4y ago
    Again, this was the entire premise. The receiver was cited as being the impossible part. I was pointing out the flaws in that argument, not claiming the entire concept was economic. By turning around and crying that I didn't say something unrelated you're being completely disingenuous.
    - throwanem 4y ago
      You made an argument that sounds like it was meant in support of the concept and I responded to it as such. It sounds like you're now saying you meant it to read as something akin to sarcasm, which is fair as far as it goes, but it is a bit rich in that case to call me disingenuous for responding in earnest to disingenuity too deeply buried or poorly executed or both for me to recognize.
      - Schroedingersat 4y ago
        Yet again, you raised the base premise as if it were some sneaky hidden thing and made the first accusation. Now you're trying to rewrite the entire conversation so that it was somehow relevant or productive. This on top of me explicitly saying the economics of the problem are probably terrible. Only an idiot or someone acting in bad faith or both would say "Aha! You need a beam with n megawatts to receive a beam with n megawatts!" Of course you do. That same solar array exists in the syn fuel scenario too (except 3-10x bigger and on the ground). Raising it as if you found a gotchya is not just disingenuous but also incredibly stupid.
        throwanem 4y ago
        I'm having a pointless argument with someone a billion subthreads deep on Hacker News. Of course it's neither relevant not productive. Stupid I'll grant you, but I've had an annoying morning and this is apparently how I'm choosing to waste a few minutes before I go on to the next thing. Presumably I'm getting something out of it, but God alone knows what. So it goes.