zlacker

[return to "xAI joins SpaceX"]
1. gok+h4[view] [source] 2026-02-02 22:06:22
>>g-mork+(OP)
> it is possible to put 500 to 1000 TW/year of AI satellites into deep space, meaningfully ascend the Kardashev scale and harness a non-trivial percentage of the Sun’s power

We currently make around 1 TW of photovoltaic cells per year, globally. The proposal here is to launch that much to space every 9 hours, complete with attached computers, continuously, from the moon.

edit: Also, this would capture a very trivial percentage of the Sun's power. A few trillionths per year.

◧◩
2. rainsf+RA[view] [source] 2026-02-03 00:24:23
>>gok+h4
We also shouldn't overlook the fact that the proposal entirely glosses over the implication of the alternative benefits we might realize if humanity achieved the incredible engineering and technical capacity necessary to make this version of space AI happen.

Think about it. Elon conjures up a vision of the future where we've managed to increase our solar cell manufacturing capacity by two whole orders of magnitude and have the space launch capability for all of it along with tons and tons of other stuff and the best he comes up with is...GPUs in orbit?

This is essentially the superhero gadget technology problem, where comic books and movies gloss over the the civilization changing implications of some technology the hero invents to punch bad guys harder. Don't get me wrong, the idea of orbiting data centers is kind of cool if we can pull it off. But being able to pull if off implies an ability to do a lot more interesting things. The problem is that this is both wildly overambitious and somehow incredibly myopic at the same time.

◧◩◪
3. byeart+1G[view] [source] 2026-02-03 00:57:24
>>rainsf+RA
So what are the other things? You said he glossed over them and didn't mention a single one.
◧◩◪◨
4. aorlof+7I[view] [source] 2026-02-03 01:11:15
>>byeart+1G
Reliably and efficiently transport energy generated in space back to earth, for starters

Or let me guess, its going to be profitable to mine crypto in space (thereby solving the problem of transporting the "work" back to earth)

◧◩◪◨⬒
5. mlindn+651[view] [source] 2026-02-03 04:02:20
>>aorlof+7I
It's always better to generate electricity on the ground than attempt to beam it to the ground from space. The efficiency loss of beamed power is huge.
◧◩◪◨⬒⬓
6. amluto+e61[view] [source] 2026-02-03 04:14:12
>>mlindn+651
The efficiency loss of nighttime is approximately 100% if we’re talking about solar energy. At least at a most basic level, it’s not totally absurd to stick some kind of power beaming contraption in space where it is mostly not shadowed by the Earth and beam power to a ground station.
◧◩◪◨⬒⬓⬔
7. ben_w+Nx5[view] [source] 2026-02-04 09:18:46
>>amluto+e61
Any process for beaming power from *outside Earth's shadow* to a point on the ground within the shadow (i.e. local night), necessarily can also send power from somewhere else on the ground that is in sun, even though the planet is in the way (ground->space->ground).

I wouldn't be too surprised by beamed power being used on Mars, because that planet has global dust storms during which nowhere on the surface is getting much light, but it doesn't make as much sense here: because of the atmospheric window, you either use 0.4µm-to-10µm-wavelengths or 10cm-to-10m-wavelengths* with not much in between, µm means lasers and the mere possibility you may have included lasers powerful enough to be useful means everyone else will demand something similar to the IEA nuclear inspection program or will put similar lasers on the ground and shoot them upward to destroy those satellites, while cm-wavelengths means each ground station is a *contiguous* roughly 10km diameter oval.

Given the expensive part of large-scale PV has shifted from the PV itself to the support structures they're on, the ground station ends up about the same cost as a same-sized PV installation, and because that's just the ground station this remains true even if all the space-side components are zero cost. Normal ground-based PV also has the advantage that it doesn't need to be contiguous.

It is also possible to use a purely-ground-based method to transfer power from the other side of the world; a cable thick enough that the resistance is only 1 Ω the long way around is already within the industrial capacity of China, but the same geopolitical issues that would make people hostile to foreign beamed power satellites also makes such a cable a non-starter for non-technical reasons.

* https://en.wikipedia.org/wiki/File:Atmospheric_electromagnet...

[go to top]