A Solar Panel Star in the Sky

_Tombstone_

China's looking to build a Station that when finished would see 6 square kilometers of solar panels orbiting the Earth at an altitude of 36,000km.

https://www.youtube.com/watch?v=BoxXlF9mepU

The electricity generated would be converted to microwaves or lasers and transmitted to a collector on Earth.

In 1941, U.S. science fiction writer Isaac Asimov published the short story "Reason", in which a space station transmits energy collected from the sun to various planets using microwave beams.

Wang Xiji, an academician of the Chinese Academy of Sciences (CAS) and a member of the International Academy of Astronautics, says Asimov's fiction has a scientific basis.

U.S. scientist Peter Glaser published an article in the journal Science in 1968, claiming a feasible design for the space solar power system.

After devoting more than half a century to space technology research, Wang, 93, is an advocate for the station: "An economically viable space power station would be really huge, with the total area of the solar panels reaching 5 to 6 square kilometers."

That's equivalent to 12 of Beijing's Tian'anmen Square, the largest public square in the world, or nearly two New York Central Parks.

"Maybe people on Earth could see it in the sky at night, like a star," says Wang.

Researchers in many countries have drawn dozens of designs, with square, round and bowl-shaped stations.

But why build a power station in space? Wang says the electricity generated from the ground-based solar plants fluctuates with night and day and the weather, while a space-based generator can collect energy 99 percent of the time.

Space-based solar panels can generate ten times as much electricity as ground-based panels per unit area, says Duan Baoyan, a member of the Chinese Academy of Engineering (CAE).

http://www.geek.com/science/china-wants-to-build-a-massive-solar-power-station-in-space-1619106/

Capt'n Midnight

Not this crap again.

Geosynch power satellites have just one function.

To justify funding of heavy launch system by promising a large demand.
eg: http://www.boeing.com/history/products/solar-power-satellite.page


The maths on these is VERY simple.

5-6 square Km of panels , 18% efficiency , 1.3Kw/m2 = 1.17 - 1.4GW


Best rectenna efficiency is 50%, maybe vs. sunlight nearly 50% of the time in the middle of the Sahara. So only 700MW at ground level

But High Voltage DC lines can carry power 1,400Km with just 5% losses.

Scale that up to 50% losses at 14,000Km and it's interesting, because at higher latitudes that more or less gets you to an evening or morning terminator to the east or west.

Yes you'd have to buy a lot more panels because you'd only max out at 1000KW/m rather than the full 24/7 1,300Kw/m in orbit. And you'd need more of them because they aren't illuminated all the time. But no launcher needed, no new technology needed. Just run jumper cables to the nearest national grid.






Even in space mirrors are lighter and cheaper, send the light down and put the solar panels down here, the main problem is that you'd blind anyone looking at them with a scope.


If you want to throw money at energy , geothermal is pretty reliable, all you need to do is reduce the drilling costs.