the earth receives the tiniest fraction of the sun's output. Space-based solar panels would have an almost unlimited amount of energy at their disposal...but how to get ithat energy down the well without James Bonds-ish laser beams?
> It states that a transmitting antenna which is synthesized from a coherent phased array of smaller antenna apertures that are spaced apart will have a smaller minimum beam spot size, but the amount of power that is beamed into this main lobe is reduced by an exactly proportional amount, so that the total power density in the beam is constant.
A big, very low-mass reflector concentrating sunlight on laser tubes tuned for various wavelengths found in sunlight, and beaming visible light at only solar intensity onto wavelength-matched solar PV farms on the ground, at night, would substitute for storage. Since the light intensity is no more than in sunshine, there is no danger.
Now when we have mining and manufacturing in space, and can use the energy there, that’s a different story.
https://illumin.usc.edu/space-based-solar-power-a-new-path-t...
Losses in transmission from space would be significant (I'm seeing 9.6% microwave efficiency) and never mind that it costs $1000/kg to put something in space.
Here is NASA's SPS-ALPHA study, which estimates 15 cents/kWh with $500/kg launch cost and minimal technological development (pdf): https://www.nasa.gov/sites/default/files/atoms/files/niac_20...
The old designs from the 1970s would have been absurdly expensive. Modern designs like NASA's SPS-ALPHA are cheap to manufacture at scale. The book The Case for Space Solar Power has a detailed cost breakdown and puts a 2GW geostationary plant at 15 cents/kWh, but was published before SpaceX did much. I plugged in Starship launch costs and it came to 4 cents/kWh, which is pretty great for 24/7 clean power without storage.
Here is NASA's study (pdf): https://www.nasa.gov/sites/default/files/atoms/files/niac_20...