Comment by abalone
12 hours ago
> using wireless communication means even less bandwidth between nodes, more noise as the number of nodes grows, and significantly higher power use
Space changes this. Laser based optical links offer bandwidth of 100 - 1000 Gbps with much lower power consumption than radio based links. They are more feasible in orbit due to the lack of interference and fogging.
> Building data centres in the middle of the sahara desert is still much better in pretty much every metric
This is not true for the power generation aspect (which is the main motivation for orbital TPUs). Desert solar is a hard problem due to the need for a water supply to keep the panels clear of dust. Also the cooling problem is greatly exacerbated.
You don’t need to do anything to keep panels with a significant angle clear of dust in deserts. The Sahara is near the equator but you can stow panels at night and let the wind do its thing.
The lack of launch costs more than offset the need for extra panels and batteries.
What’s your source for that claim? Soiling is a massive problem for desert solar, causing as high as 50% efficiency loss in the Middle East.[1]
[1] https://www.nlr.gov/news/detail/features/2021/scientists-stu...
A relevant quote from that article.
“The reason I concentrate my research on these urban environments is because the composition of soiling is completely different,” said Toth, a Ph.D. candidate in environmental engineering at the University of Colorado who has worked at NREL since 2017. “We have more fine particles that are these stickier particles that could contribute to much different surface chemistry on the module and different soiling. In the desert, you don’t have as much of the surface chemistry come into play.”
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Space doesn't really change it though because the effective bandwidth between nodes is reduced by the overall size of the network and how much data they need to relay between each other.
Yup. We don't use fibre optics on earth rather than lasers because of some specific limitation of the earth's surface being in orbit would avoid.
We use them because they're many orders of magnitude cheaper and simpler for anywhere near the same bandwidth for the distances required.