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Erm... this isn't a very popular topic with you lot, is it?

Ah well...

I guess y'all wouldn't really be interested in how one would make the Sail Material either?

Well, I'll tell ya anyways;
Basically, you make the Plastic through a System that looks like this, and has a thin layer of Aluminium put ontop by evapourating some Al and exposing the surface to the resulting vapour.

Sorta like a crisp packet, but slightly stronger and more reflective (up to 99% of the light it hits it will be reflected (main source)

Well, no, more a method of collecting it; using such a sheet as a method of focusing Sunlight onto a pipe and running water through it could give a lot of steam for turning a turbine - meaning a lot of electricity.

Since the density of Sunlight at this Orbit from the Sun is about 3 kilowatts per square meter, a reflector several kilometers in diameter could easily aquire all the energy needed for a reasonably sized City to live off of - 24 hours a day, cheaply and reliably.

Building such a large quantity of material wouldn't be too difficult either - it would only weigh a few hundred kg if made from Aluminium foil (much less if made from the Aluminised PET I was talking about earlier, but that would be more difficult and expensive to manufacture on The Moon and it's weight doesn't matter - quite unlike Solar Sails, of course).

Compare that to all the difficulties you would face through using, say, a Nuclear energy source, and you can see why I think it would be the best option for Civilian Power.

What do you think?

Am I wrong about this?

Would contained Fusion be even better?

Lol, there's more than enough Sunlight on one side to provide all the Power you could possibly require.

A few collectors at Earth Orbit would be enough to power Earth and every Colony you could feasibly put above it.

Well, you use the electricity you make to generate a ******** enourmous Microwave Beam and point it at a bunch of rectennas on the ground, which convert the Microwaves back into electricity when they get there.

Rectennas are simple, cheap, reliable and very effective at what they do - converting Microwaves back to electrical current at somewhere on the verge of 90% efficiency, though we will likely be able to make ones that get much higher than this.

Microwave generator Technology is very mature (we've had it for ages) and we can make frequencies perfectly suited to traversing the thick Atmosphere with ease using it.

I really like your idea, if worked out properly it can be quite a good way to collect energy.
But the main problem with them would probably be that the reflector/microwave generator combo wont stay in one place/the place you want it to stay, because of gravitational pull. So you would need thrusters for that to keep it in place.

But as for the microwaves, isnt there a danger that when the microwaves miss the collector on the planet they might boil a nearby town, or am i thining about the wrong microwaves.

And i thouht they already had som quite good solarsails, or i might have watched tv a bit too much again.

Now, why would a silly thing like Gravity defeat the ambitions of such an imaginative species as ours? smile

lol, seriously though, if you keep it at an Orbit far away enough from the Atmosphere that there will be practically no particles around to slow it down, why should it's Orbit ever degrade enough for it to fall out of Orbit?

The only reason some things we put up there start to come down again is because we keep them within the Upper Atmosphere - which isn't very dense, but dense enough that air resistance very slowly soaks up their energy and makes them drop down again.

A High Earth Orbit solves this.

Oh, well you've got a point - the amount of energy coming down in the beam will be very high, otherwise we wouldn't be able to use it as a power source, but that beam will be spread out enough that that energy is spread out to the point where it's barely the density of Sunlight on the Surface.

See, Sunlight has an energy density on the ground of about 1500 watts per meter squared.

If you get, say, 1 square kilometer of rectenna on the ground, you could get 1.5 billion watts collected from it - which is enough to power a decent sized town.

Now, we don't have to go this far - microwave densities on the ground could easily be made 2 or 3 times the density of Sunlight without there being any significant risk to anyone walking directly over them, and virtually none to everyone who doesn't go near the things, and get enough power to run a City off of from a collection of rectenna not much bigger than a square kilometer.

See, we can't just shoot it all down like a "Death Ray" because any little jitters on the generator up in Orbit would cause the beam to move all over the place on the ground - we'd never be able to keep it steady enough to reliably collect power from it.

When the rectenna collections are a kilometer wide, though, a few little imperfections in our targetting wouldn't be the end of the World for us, because virtually all of it would still land where we want it to.

lol, sorry, but we've not tested anything close to the size I was thinking of yet.

We've probably had a few Sattalites up to test the principle, but they'll only really get the most out of it if the sails are really big.

lol, so what? smile
it's many kilometers in diameter and held in place by a sturdy skeleton, so most things that hit it will just go straight through, leaving a small hole which can easily be repaired later if you like - you'll be reflecting so much with the rest of the thing that it honestly won't matter.