2 ms·

Yeah everybody knows that. But transmission by wire halfway around the globe would be pretty expensive, and carry geopolitical risks.

pengaru 4y ago
> and carry geopolitical risks. And a solar death ray aimed at the planet doesn't?
- DennisP 4y ago
  As I noted in another comment, it's not a death ray. Even with a reference signal from the ground, it's not concentrated enough to cause harm. Regardless, I don't think long-distance transmission is a viable solution to solar intermittency.
  - LargoLasskhyfv 4y ago
    But it could be? Becaus phased array? See also https://en.wikipedia.org/wiki/The_Noah%27s_Ark_Principle https://en.wikipedia.org/wiki/The_Noah%27s_Ark_Principle
    - ben_w 4y ago
      Not for a single device with a fixed wavelength and size; unless someone figures out a way to cheat quantum mechanics and the diffraction limit, how well you can aim light is directly related to the size of your aperture (/antenna) in wavelengths. Convincing governments you've not cheated with a gigawatt optical laser on your satellites (optical wavelengths being smaller than microwaves makes them easier to focus with smaller parts), that's a separate question. I assume an Iranian one of these would get destroyed by Israel for the same reason they attack their neighbour's nuclear reactors.
  - ben_w 4y ago
    One isn't a death ray; but if you only have one, then you need a global power grid anyway. If you have enough satellites to not need the distribution grid, and they're all in geostationary orbit, then many are over the horizon at the same time and they can (in principle) be combined on the same place. If they're in a low enough orbit that you only get a few over the horizon at any given moment, you get a substantial penalty from Earth's shadow. On Mars this would be a great thing for colonies; get past the global dust storms, and it won't matter if you have only a handful of sites; on Earth… pick which failure mode you prefer.
sidewndr46 4y ago
Is transmitting power from a satellite in low-earth-orbit going to be cheaper?
- DennisP 4y ago
  Possibly. Long-distance high-voltage wires get pretty expensive. At Starship launch costs with modern designs, SPS actually looks pretty economical.
  - sidewndr46 4y ago
    If someone has compiled a cost comparison of transcontinental HVDC links compared with the alternative spaceborne solution I'd certainly love to see it. The space based solution is possibly actually more reliable, as there are actually less components involved that could fail.
    - LargoLasskhyfv 4y ago
      No protective atmosphere. More (micro)meteorites.

pengaru 4y ago

> and carry geopolitical risks. And a solar death ray aimed at the planet doesn't?

DennisP 4y ago
As I noted in another comment, it's not a death ray. Even with a reference signal from the ground, it's not concentrated enough to cause harm. Regardless, I don't think long-distance transmission is a viable solution to solar intermittency.
- LargoLasskhyfv 4y ago
  But it could be? Becaus phased array? See also https://en.wikipedia.org/wiki/The_Noah%27s_Ark_Principle https://en.wikipedia.org/wiki/The_Noah%27s_Ark_Principle
  - ben_w 4y ago
    Not for a single device with a fixed wavelength and size; unless someone figures out a way to cheat quantum mechanics and the diffraction limit, how well you can aim light is directly related to the size of your aperture (/antenna) in wavelengths. Convincing governments you've not cheated with a gigawatt optical laser on your satellites (optical wavelengths being smaller than microwaves makes them easier to focus with smaller parts), that's a separate question. I assume an Iranian one of these would get destroyed by Israel for the same reason they attack their neighbour's nuclear reactors.
- ben_w 4y ago
  One isn't a death ray; but if you only have one, then you need a global power grid anyway. If you have enough satellites to not need the distribution grid, and they're all in geostationary orbit, then many are over the horizon at the same time and they can (in principle) be combined on the same place. If they're in a low enough orbit that you only get a few over the horizon at any given moment, you get a substantial penalty from Earth's shadow. On Mars this would be a great thing for colonies; get past the global dust storms, and it won't matter if you have only a handful of sites; on Earth… pick which failure mode you prefer.

sidewndr46 4y ago

Is transmitting power from a satellite in low-earth-orbit going to be cheaper?

DennisP 4y ago
Possibly. Long-distance high-voltage wires get pretty expensive. At Starship launch costs with modern designs, SPS actually looks pretty economical.
- sidewndr46 4y ago
  If someone has compiled a cost comparison of transcontinental HVDC links compared with the alternative spaceborne solution I'd certainly love to see it. The space based solution is possibly actually more reliable, as there are actually less components involved that could fail.
  - LargoLasskhyfv 4y ago
    No protective atmosphere. More (micro)meteorites.