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0 pointsvessenes11d ago0 comments

All questions/comments that I don't know enough to opine on.

But, power density in terrestrial I think we can do some math and reasoning:

First, oceans are WAYYY more hostile than space. Oxidation + salt water + .. I don't think it's even close there. I don't think they are comparable.

Deserts and trackless wastelands - I have some experience with sub-Saharan logistics; a couple of points -- I would not be surprised if actual deployment to trackless wastelands is more expensive than lift. Analysts estimate $55k-85k per ton under starship. (Elon estimates much lower; let's stick with low end of analyst numbers).

Trackless wastelands are really hard to get to. For instance, I've seen a fuel truck tipped over on its side in a river next to a small tow truck tipped on its side in a river next to a larger crane trying to rescue the original truck and the "rescue" truck in Southern Kenya -- by no means a trackless waste -- probably a week long ordeal, JUST for diesel delivery. This was in an area under former British rule with roads and stuff.

Second, trackless wastelands are really hard to find. There are people everywhere, man. And they like free metal, free power, etc.

If we imagine instead just deploying to West Texas, I think the square footage does add up. 40 foot container -> call it 16 racks. Nvidia estimates 600kw per rack in 2027 with Vera Rubin(!!JFC!!). So, 10MW of power per container. Let's imagine we magically found water in West Texas and have a PUE of 1.2, so 12MW. Solar panels are like 20 W/sq ft.

I got lazy; Claude tells me with 2.5x land needed for spacing, infra, etc, 6.5 peak sun hours, a couple of acres for storage, roughly 130 acres (0.2 sq miles) + 53 Tesla megapacks for storage per container.

I'll revise my above thoughts - there is NO WAY it's cheaper to do that in trackless wastes than space. I don't know about west Texas, but I don't think it's crazy to think that you might want to spend five years on engineering and production scaling instead of town and county and state and federal permitting.

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CamperBob210d ago

Granted, some compelling points against the "trackless wasteland" plan. All of them sound pretty valid to me.

Oceans, though -- we know how to deal with saltwater environments, we've done that for a while now. A key point is that anything you send into space or install near saltwater isn't going to last long without either regular maintenance or high up-front expense. But in this case, the equipment only has to last a few years until it's obsolete anyway, and ~5% FIT is probably tolerable. So I maintain that it's doable.

One good thing about an ocean-based platform is that it makes the heat dissipation problem go away virtually for free.

None of the challenges of running a 10 MW container full of hardware go away in space (other than the threat of nomadic scavengers, I suppose.) Yes, space-based PV arrays are smaller and lighter... but that's it, big deal. In particular, the idea of getting rid of that much heat in space without the benefit of convection, conduction, acres of expensive radiators, or magic is beyond my ability to comprehend, much less address. Everything having to do with heat removal is much harder in space.

So, given that you aren't going put 10 MW worth of hardware in a single satellite anyway, it doesn't seem valid to compare such installations on an equal basis as you're doing here. The 130-acre site you mention doesn't replace one satellite, it would probably replace a thousand of them.

You get a lot of expensive redundant requirements when you split up the problem that way, as well. These requirements will eat up any savings you might get from space-based deployment. Instead of one communications link with expensive RF hardware, you now need a thousand. Likewise, it's cheaper to build one 10 MW power substation than a thousand independent 10 kW power management solutions. And remember, this is all to support a single shipping container worth of hardware.

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