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TimeSpentWasting OP t1_ixzcmaf wrote

Reply to comment by seidler2547 in News Release: NREL Creates Highest Efficiency 1-Sun Solar Cell - 39.5% efficiency by TimeSpentWasting

Never knew why, now I have the answer without googling. I'm lazy, so thank you

I have high hopes that humanity will reach that maximum value as tech gets smaller. I wonder how much efficiency is reduced under heavy cloud cover?

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skittlesmcgee33 t1_ixzuftk wrote

That maximum is functionally impossible. Functional limit is in the 40-49% range so we’re already most of the way there.

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PM_Your_Wololo t1_iy0pk6k wrote

Can you ELI5 why the difference is so large?

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ThatOtherGuy_CA t1_iy0ubqo wrote

Material costs, eventually the amount of materials you need to add per extra % is more than just building a second panel at the same efficiency. So around 50% in order to get an extra 1% in efficiency, you need a panel with double the cells. So you might as well just build 2 50% efficiency panels rather than 1 51% one.

That’s basically why most panels are stuck around 23% right now, it’s more cost effective to just build 2 panels than to build a panel 1% more efficient.

Basically as technology advances it gets easier to improve the efficiency with less waste, but around 50% is when you can’t really make anything smaller to get those efficiency gains in a similar sized panel.

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LouSanous t1_iy4302w wrote

>So you might as well just build 2 50% efficiency panels rather than 1 51% one

The most recent info I was able to find shows it to be like 300:1. Standard utility scale solar panels in the 20% efficiency range are 1/300 the cost of triple junction GaAs.

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ThatOtherGuy_CA t1_iy47zui wrote

Yup, which is why you pretty much only see them in space applications. Because the weight saved can save enough fuel costs to offset the insane price increases.

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LouSanous t1_iy4fmek wrote

I'm not sure how much it costs spaceX with their reusable rockets (and given that Musk is in charge, I would bet that he never did achieve the multiple orders of magnitude cheaper costs he promised), but prior to the space shuttle cost per kg into space was $18,500. After the space shuttle, $54,500/kg.

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