I wonder whether this meant to imply military capability, in the same way that the space race was basically a way to advertise ICBM capabilities.
In the sense that fancy hats imply virility.
China wants to put a solar farm in space by 2025
21–30 of 62 posts
Re: China wants to put a solar farm in space by 2025
#22Re: China wants to put a solar farm in space by 2025
#23Finally, somebody decided to make solar collectors in space. Been waiting for it since it was discussed in Isaac Arthur. I bet spaceX might do something similar in the future. When they are not as encumbered with star link and the BFR.
1) It is not much more efficient due to transmission losses. (Compared to high voltage DC.) 2) The costs, on top of super expensive solar panels, make this totally pointless economically. Solar panels are hard enough to maintain on Earth. 3) It's a multi gigawatt level microwave gun in space. Want to blast some lightning onto someone? Sure, now you can. Or fry it.
> Solar panels are hard enough to maintain on Earth.
Isn't the main issue that they get dirty, though?
Re: China wants to put a solar farm in space by 2025
#24Earlier quoted context omitted.
Its in the article >China's proposal, meanwhile, appears to suggest converting solar energy into electric energy in space, before beaming back to Earth using a microwave or laser and feeding into the grid via a ground receiving system.
Short version: they can fry a target in any country in about a day.
If the country is small enough they can fry that too. I can think of a likely candidate already.
Re: China wants to put a solar farm in space by 2025
#25A doomsday weapon in space.
As the article mentions, the station will beam the collected energy down to Earth. Whether in visible light, microwave or any other spectral band, it will need two things for everyday operations:
- ability to point the beam at an arbitrary point on Earth, to track the collector ground installation, and
- ability to focus the beam to proper size
The second capability is crucial; if it's fixed focus - and one with sufficiently large footprint at that - and fixed orbit, it would be safe.
However having either adjustable focus, or adjustable orbit[1] makes this a proper weapon, due to the possibility of pointing multi-megawatt beam of energy at any point on the ground, with little to no countermeasures available. Whether "rogue hackers", or actual owners of the station, somebody would have the capability to destroy, without warning, large swaths of infrastructure on the ground.
I sure hope I'm very wrong about this - that somebody have figured out a way of inherently neutralizing the danger. But for now I treat the project as a doomsday weapon in space.
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[1] the later is a given to an extent, due to the need for orbital stationkeeping, and only possible to limit via provision of weak engines and/or limited fuel loadout
Re: China wants to put a solar farm in space by 2025
#26Finally, somebody decided to make solar collectors in space. Been waiting for it since it was discussed in Isaac Arthur. I bet spaceX might do something similar in the future. When they are not as encumbered with star link and the BFR.
1) It is not much more efficient due to transmission losses. (Compared to high voltage DC.) 2) The costs, on top of super expensive solar panels, make this totally pointless economically. Solar panels are hard enough to maintain on Earth. 3) It's a multi gigawatt level microwave gun in space. Want to blast some lightning onto someone? Sure, now you can. Or fry it.
3.5) The giant MASER in space is also a sitting duck target, so it’s shit as a weapon, and disrupting a nation’s power supply is as easy as “shooting” back.
Re: China wants to put a solar farm in space by 2025
#27A year ago I read the book The Case for Space Solar Power, which goes into the engineering in detail.
The old SPS designs from the '70s were monolithic beasts that would have been ridiculously expensive. Current designs would use a large number of identical parts, of about eight types, which would self-assemble in space. That way they can be mass produced in factories.
The basic design was PV with microwave transmission, which has already been tested over distances of ten kilometers or so. (Iirc it was between a couple Hawaiian islands.) The receiving station sends a sort of homing signal for a phased array transmitter, which makes it difficult to redirect to somewhere without the homing signal and keep a reasonably focused beam, though you could switch between multiple receiving stations (which are fairly cheap). The station would be in GEO.
The book did some detailed cost analysis and found that with pre-SpaceX launch costs, the SPS could provide power at 15 cents/kWh retail.
Elon Musk has said that at scale the BFR could ultimately get to a $50/lb launch cost, so for grins I plugged that number into the book's calculation and got 4 cents/kWh.
Since this type of solar would work through the night, with little or no need for storage, it could be pretty competitive.
book: https://www.amazon.com/Case-Space-Solar-Power-ebook/dp/B00HN...
Re: China wants to put a solar farm in space by 2025
#28How would they prevent overheating?
Re: China wants to put a solar farm in space by 2025
#29A doomsday weapon in space. As the article mentions, the station will beam the collected energy down to Earth. Whether in visible light, microwave or any other spectral band, it will need two things for everyday operations: - ability to point the beam at an arbitrary point on Earth, to track the collector ground installation, and - ability to focus the beam to proper size The second capability is crucial; if it's fix…
It's a pretty shitty weapon because many countries have the capability to launch a bomb to the satellites and the satellites are way more expensive than the bomb.
Re: China wants to put a solar farm in space by 2025
#30With regards to climate change and global warming, what about putting this in between the sun and the earth to block some of the energy reaching the planet to allow it to cool?