Aussie Enviro

Don't worry, general physics means that this is just another investment scam.

I'll explain it out so you can get the general idea;

In order to reflect a sun's worth of sunlight, you need a reflective surface in low earth orbit that is somewhat larger than the angular size of the sun from our perspective on the ground. Imagine just using an ordinary mirror at home, you need to see the whole of the sun in it, and that works out to be about a little mirror about the size of your thumb at arm's length. In low earth orbit that mirror ends up being about 2km across.

To get that kind of reflective surface area in orbit you need about a couple of thousand 50 metre wide reflectors on satellites, just to reflect light to a single location with the rough equivalent of sunlight.

And then at the height of low earth orbit the earth eclipses the sun for quite a bit of time, so the sats that can see the sun during the night below on Earth are actually only able to do so for a couple of hours before sunrise or after sunset. So now you need to launch 10x more sats so that the sats that can see the sun can reflect light to where you want it.

So let's just say 20,000 sats to start with.

With some clever engineering, you could probably make them the same size as SpaceX sats, and they launch about 25 at a time for a customer cost of about 70 million USD.

My calculator says that the launch cost for this is 56 billion USD. And then sats in that orbit with huge, high drag panels will get pulled into the Earth's atmosphere after about 5 years, so you just need 56 billion up front plus about 10 billion a year to maintain the constellation, forever, and with all of that stuff flying around up there you can direct 1 suns worth of solar energy to 1 location.

Now you could take that array and split it up and provide, maybe a moonlight effect to a hundred places, and maybe, maybe, a hundred someones might pay the hundred million a year to feebly light their city streets or something. Seems a bit of an ask when there's plenty of ways already to turn night into day locally for a lot cheaper.

BUT - you could also repurpose those 20,000 sats to provide a dozen sun's worth of energy to any point on earth during the day when about half of them can easily see the sun.

This sure sounds like a practical equivalent of a death ray to me, which means all this bullshit will never get anywhere because no country in the world will allow anyone to build it.

So rest easy, this is just another way to scam venture capitalists and won't go much further than these press releases.