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Waslw t1_ja4i31c wrote

Better materials are great and all… the main issue with solar is even if energy transfer was 100% efficient, there is a finite amount photons per square cm, so eventually it’s a surface area problem and never having enough of it.

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Philbot_ t1_ja4m9fx wrote

Full direct sun is around 1000W/m2. A tennis court is around 200m2. 200kW can power a large office building with a roof area of multiple tennis courts.

If we had 100% efficient solar panels, humanity would be set for a very long time.

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Waslw t1_ja4oejf wrote

I’m not knocking the tech and I know the math… and as far as where we are today in our energy needs it’s promising, in my opinion things like nuclear are still superior because of shear energy density. Thorium is 35 times more energy dense than Uranium. 1 Kg of Uranium has an energy density of 45,000 kWh, 1 Kg of oil 12 kWh and 1 Kg coal only having 8kWh.

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gulgin t1_ja4pg9h wrote

Everything is relative. It is unlikely that fusion will ever be as scalable or reliable as solar. Solar panels are so incredibly simple that they will always be more efficient than fusion in certain circumstances. That being said, it is possible that fusion would be more efficient in different circumstances where high power density is required or solar suffers from environmental issues. One is not better than the other, any more than a carrot is a better vegetable than broccoli. They are both good. For better or worse solar is shooting up the maturity ladder much faster than fusion, but fusion will get there eventually. (I hope)

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Waslw t1_ja4uwu6 wrote

I think your confused… I’m not talking fusion, I’m talking fission, technology that has existed and has been used for many many decades… arguably out of all the “green energy” technologies that exist today it is the most scalable, affordable, safest as far as deaths, injuries and illnesses (that includes aftermath of things like Chernobyl, Fukushima, and 3 mile island) … and over its life the only energy technology that is truly carbon neutral and with little improvement carbon negative.

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gulgin t1_ja4w4t6 wrote

Apologies, I assumed you were talking fusion. Either way the exact same arguments apply. Fission is still necessarily much more mechanically complicated than solar and will never be as reliable or maintenance free. I am also not sure how you are considering nuclear safer than solar, but in the long run the safety stuff gets solved either way so I wouldn’t hold that against either technology. Carbon neutrality is also a very complicated question, environmental impact is a difficult if not impossible thing to holistically judge.

Either way, there will always be situations where solar is a better energy production method than any kind of nuclear, and there will always be situations where any kind of nuclear is better than solar. As the technologies develop that crossover point will swing back and forth.

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SandAndAlum t1_ja5ttbg wrote

Closed fission fuel cycles are scifi, safe, clean thorium separation doubly so. And the largest uranium mines and deposits like Inkai would produce more power as solar farms than uranium mines.

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peadith t1_ja4lc0w wrote

Yeah but 1kW per square meter would still kick ass.

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dwkdnvr t1_ja4qmcp wrote

There are problems with Solar to be sure, but surface area is not one of them.

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Waslw t1_ja4vmd4 wrote

I’m not saying it’s problematic… I’m just pointing out a simple function of the limits engineering… the biggest problem is electricity needs to be consumed the instant it’s produced and there just isn’t an energy storage technology available today that is efficient enough to make it viable.

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SandAndAlum t1_ja5u93m wrote

It's called putting water on top of a hill and it's existed for millenia. It's not widespread because there isn't enough VRE or inflexible generation like nuclear to require it yet.

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ArOnodrim t1_ja4rd6x wrote

If you covered an entire house in California, it could reasonably power 10 homes every day. If you covered a parking lot in California, it could power multiple buildings. 200 Sq km of empty Arizona desert could power the entire US right now.

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allenout t1_ja4sx85 wrote

Thankfully perivskites should be significantly cheaper than silicon solar panels.

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Personal_Problems_99 t1_ja533w0 wrote

It's not even just a surface area problem though. If it was indeed 100 percent efficient... You could use lasers to transport energy from point a to point b.

You can condense light into a very small area.

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SandAndAlum t1_ja5tkuo wrote

Even in northern ireland in mid winter GHI is about 1kWh/m^2

That is over 1kW time averaged hitting the space required to park a single car. A small 2 bedroom apartment sharing its roof are with apartments above and below has about the world average final energy hitting its roof in ireland in mid winter.

Space is not even slightly a problem.

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