Comment by stingrae
1 month ago
“A 5 GW data center would require a solar array with dimensions of approximately 4 km by 4 km”
I think dodging debris is challenging at that scale.
Also this is the solar cells not the radiators
1 month ago
“A 5 GW data center would require a solar array with dimensions of approximately 4 km by 4 km”
I think dodging debris is challenging at that scale.
Also this is the solar cells not the radiators
Desert land is full of that amount of area available for peanuts.
That’s 4000 acres. I see a 6000 acre ranch available in Arizona for $7m. The cost of building a 5GW DC is about 100 billion. Land including enough for all the solar and battery you need to be completely self sufficient is basically free.
You can fly a drone laden with fireworks across a desert. Harder to do in LEO
The only reason I see in putting those things in space is to do illegal things. Otherwise the economies do not make sense. The "terrorism" threat is nearly non existant in practice and only the legislative threat is real, which might be good cause to think about what you are doing in the first place.
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cheaper to defend on earth than launch and maintain in space.
Presumably that’s not a single satellite.
Nope, it's a single massive panel sat and they're using $30/kg as their launch costs.
Up to you how plausible you think that is.
There's an artist's impression of the frigging thing in the whitepaper! It's very obviously a single enormous thing!
> Figure 3. A data center in Sun Synchronous Orbit, showing a 4km x 4km deployed solar array and radiators.
Right, the goal here is a more realistic Dyson swarm, not a Dyson sphere (yet)
I wonder if the shadows from such a large area would have a climate cooling effect?
The Earth's surface area is ~ 510,000,000 km^2. For simplicity, say exactly half of it is receiving sunlight. If the satellite perfectly shadows 16 km^2, it would reduce incoming solar energy reaching Earth by 16/205,000,000 = 0.00000078%, I think.
So not really. There are some proposals for space-based geoengineering, https://www.sciencedirect.com/science/article/pii/S146290112... has a summary. I can't say how plausible any of them are.
Ideally you'd put it in an orbit that wouldn't shadow earth, since if it goes in front of earth in part of the orbit then it'll go behind earth (and be in shadow) for part of the orbit. They mention they'd want it in a dawn-dusk sun-synchronous orbit, which would be in sunlight all the time and would never shadow the earth.
How can this practically work though? As Earth goes around the Sun 90 degrees, orbit will become half-shadowed.
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Would be cool if so, but I wonder what the plan is regarding radiation pressure pushing things out of orbit.
would radiation pressure not counterbalance the radiation pressure from the sun?
given solar cells are only 30% efficient. if you put the radiators behind the panels then you have the structure already and always keep the radiators shaded
I think the principle is correct but probably it would need to be much bigger.