Devil wrote:1) Tell me how you are going to generate "several hundred megawatts" of microwave power. To generate 1 kW of CW microwave power (not pulsed) is already a challenge. I don't believe we have the technology for even a single MW.
We don't need CW, plan calculates with normal 2450MHz transmitters similar to microwave owens
There si probably going to be array of them on sattelite.
The problem is, that you need large array of transmitters, to limit divergence of rays.
2) Bearing in mind the inefficiency of CW TXs at those frequencies, I would imagine that, for a 500 MW space station, you would need about 4 to 6 km2 of solar panels to power it. How are you going to get them up there?
Yes, one of the major problems. It calculets with modular design and many normal launches, but nothing undoable, just very costly.
If we are going to build large ammount of such things, it's really much much cheaper (energy wise) to launch material from Moon, or build space elevator
3) As such a station would need to be in geostationary orbit above the receiving dish, it will be in the dark for half the time.
Erm, check the orbits
It's not in shadow 1/2 of day, in fact it's in light 24/7 ! (Just rare do eclipses though happen).
4) How do you overcome atmospheric diffraction changes?
Diffraction affects MW minimally, and happens at relatively low altituted. Rectifier antena will be bigger than neccesary and probably of ellipse shape and will handle tiny changes.
5) It is simple physics that if you increase the radiation energy into the earth's biosphere, so the latter will become warmer. However, half a dozen such stations would not make much difference.
Yes, but just compare this energy to total solar energy we receive. Really, several GW change nothing..
6) What will you do with all the roast birds that will fall to earth (not to mention aircraft that inadvertently pass through the beam
Intensity near Earth is going to be just about 20-30mW per square cm (5mW can leak from MW owen by US standards), it won't kill anything. Birds can fly over it.
7) How will you perform maintenance on a geostationary device using thermionic components?
Biggest problem. Maintenance and servicing costs will be huge. SPS will receive constant damage from sun, space junk and micrometeorites..