Should you invest in Spacex?
2 Trillion dollar thing. Data centres in space
Power is free from the sun, and it's cold, so cooling is easy.
Elon says.
I think he's fibbing.
Date centres use gigawatts of power. A big one would be a Terawatt.
Solar incident power is of the order of 1kW per square metre. It's a little easier in space because of the exposure and no night. The lack of air makes almost no difference.
So you need a solar collector . Lets assume they're 100% efficient - they're only about 20% really.
1TW is 10^12 W
10^12 / 10^3 square metres
That's 10^9 sq m.
You could use 10 panels 10^4m x 10^4m
That's 10 square panels, ten kilometers on each side.
Origami anyone?
Then there's the cooling.
Yes it's cold in space. 3Kelvin or so.
But the "it" is almost nothing. It's a vacuum!
So there's no stuff to heat up and move away from your data centre carrying the heat.
You can use radiative emission. That sounds good, because , if you remember skule fiziks, it's proportional to the temperature difference to the power 4. Do the names Stefan & Boltzmann ring a bell?
Your chips run at say 50C which is 323K
Then you plug in the constant, which is 5.670367 × 10⁻⁸ W·m⁻²·K⁻⁴
Spot the pesky -8 in there.
It comes out that you need about 1 order of magnitude less for the size of radiator to cool the thing, than you needed to get the energy.
And they're really heavy, compared with solar collectors. You need a couple of thousand square kilometers of the things, all got there by rocket.
Oh, and the data centre itself would be pretty big and heavy. Maybe 100 square kilometers, but they're definitely three dimensional.
Then there's the maintenance problem
and bits of space junk flying about
and the little NVIDIA guy in the shiny black jacket updates his chips every year.
I'll stick to day trading Spacex.