We already have that nuclear reactor beaming energy down for us to collect.

It's just too bad the planet keeps getting in the way.

And sometimes the moon.

I support nuclear but if you're beaming power from space, it might as well be from solar panels. In geostationary orbit you have power 24/7, with 5X more sunlight per day than panels on the ground. The only time your satellite goes into shadow is for a few minutes per day around the equinoxes, half an hour max. Capacity factor is still over 99%.

Basically Gundam 00 haha. I was young when it aired, but it left a long lasting impression of what the future of space exploration might be like. Space elevators and massive solar arrays around the planet.

It’s not the worst idea, but we kind of need to get the whole orbital elevator but done first before the massive planet-spanning solar array.

Truth though: I think Gundam 00 showed a shockingly plausible future (sans mechas, most likely) for our planet if we do not get over our reliance on fossil fuels. Global conflict on a scale that makes WW2 look like child’s play is an inevitability if we cannot mitigate the environmental impact and eventual depletion of fossil fuels, and that includes support to help less developed nations move away from them.

It's too easy for space junk to destroy it, also a single point of failure or attack. It's a terrible solution as long as we remain a warlike species.

I hate to break it to you but most of our power stations are vulnerable to attack already. Certainly anything near the coast could be taken out by our major adversaries, even with conventional attack.

For a lot of plants, an anonymous cyberattack could probably do it. That'd be way worse than an attack to geostationary, which very few actors could manage, and probably nobody could pull off anonymously.

Space junk seems a more serious problem:

https://physicsworld.com/a/space-debris-threat-to-geosynchro...

I've seen various proposals to clean it up but it'd take some work.

With geostationary? Don't they track a location on the earth? Is the satellite not in the earth's shadow at night?

Geostationary is super far out— you're effectively in constant sun:

https://en.wikipedia.org/wiki/Geostationary_orbit

Except, as the parent noted, very briefly during the equinoxes.

And even that seems "easy" to circumvent by having redundant satellites, such that during the equinoxes (equinoxen?) only a fraction of said satellites are shadowed out at once. Alternately, a massive battery or capacitor bank could give the receiver enough buffer to hold out through an equinox-induced shadowing.

Interesting idea, but my next thought was "how are you going to cool that thing?!" :D

Not sure in which direction you're joking, but heat dissipation can actually be a difficult problem in space, at least as close to the sun as Earth is, while outside Earth's atmosphere. For example: https://science.nasa.gov/science-news/science-at-nasa/2001/a...

That's exactly what I meant. Running a nuclear fission reactor (along with the high power beams to Earth) in vacuum might prove... problematic.

But then you have nuclear-powered space lasers, which will scare people.

Yeah, but if people don't like it, what are they gonna do? Complain? That'll just draw the attention of the nuclear-powered space lasers :)

Or it could blow away the Van Allen belts and fry everything else in orbit, then drop plutonium somewhere.

How does one efficiency “beam down” gigawatts of energy? Or at all?

Microwaves. Ground station has to be several square kilometers, but it's cheap and birds can fly through the beam without harm.

For economic reasons you pretty much have to use phased array transmitters, with a reference signal from the ground to make it coherent, so if the beam gets repointed it gets a lot more diffuse than that.

I've seen how this plays out in SimCity. No thank you!

Light. Focusing mirrors or lasers.

But as others have pointed out, why would you bother with building space based nuclear plants and then converting that energy to light when you could just use the sun?