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Roll-to-roll fabricated perovskite solar cells under ambient room conditions

nature.com

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Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#81

Post by fbdab103 »

philipkglass wrote: post #70
fbdab103 wrote: post #65

Wondering if anyone could help shore up my understanding or point out a resource to get me a better handle on this. Using the solar maps from here[0], you can find the kWh/day/m2 for the US. If I am in a say 5.7 kWh/day/m2 region and I have 1 m2 of a 20% solar efficiency panel, does that mean I would get 1.14 kWh usable out the other end? Or is it 20% * X% horribly lossy conversion factor? If I want to math out 11kWh…

You'd be able to generate 1.14 kWh at the panel level if you kept the panel pointed directly at the sun throughout the day [1]. This is called "2 axis tracking" and it was sometimes used for solar farms when solar panels were much more expensive. Now that panels are much cheaper, 2 axis tracking has practically vanished from the market. The added expense and mechanical complexity isn't worth it. Single axis tracking,…

So, the bottom line is that the simple kWh/day/m2 * panel efficiency * m2 of panels should be within the theoretical ballpark of generation, but the real world is a harsh mistress and will undercut you.

On that calculator resource, they provide a monthly and hourly spreadsheet, but even with the more detailed numbers, I was still failing to corroborate their presumably much more sophisticated modelling which accounts for other losses.

Thanks. Just spit balling numbers and trying to see what things look like.

Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#82

Post by refulgentis »

KennyBlanken wrote: post #80
beanjuice wrote: post #53

My two cents having formerly worked in perovskites trying to upscale the process: Perovskites are exciting (or were exciting) because they have a high theoretical efficiency, are relatively simple to prepare, and the "worst" component in them is lead (an incredibly abundant material). The big problem with them is that they are famously horrifically unstable in ambient conditions. Roll-to-roll processing means that yo…

Solar panels "produced from rare earth minerals" is "under-reported" because they are not made from rare earth minerals , and further: the minor metals they are dependent upon are byproducts of refining base metals, ie there isn't much additional impact from using them; we already make them. I'm not really sure how someone who supposedly worked in solar panel research would think rare earth metals are used in solar p…

This is true: i.e. they use rare metals not rare earth metals.

On HN, I hope we can share a correction like that respectfully: after all, they gave good info, except for a one-word slip of the tongue.

The critique seems to extend beyond correcting that error, becoming confrontational, questioning motivation and honesty with phrases like "supposedly worked in." and the long bit defending lifespan and enviromental impact against people who "don't seem to have a problem with oil drilling, fracking, coal strip mining, etc" - they didn't even touch on that subject.

Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#83

Post by RisingFusion »

Workaccount2 wrote: post #33
londons_explore wrote: post #7

The market need for cheaper solar cells seems to have evaporated, since the vast majority of the cost of solar projects these days is always in labour/land/wiring/inverters/grid connection/maintenance contracts. That means saving a bit of money on the panels in return for lower efficiency is never a good deal.

I've been waiting for consumer level panels to get cheaper forever. You'd think by now that you could get a 200W panel for $50. But they have been the same $200 for what seems like a decade now (I suppose they didn't go up with inflation, but still)

In Germany, 405 Watt panels new can be had for 65 euros. The law allows up to 800W to be connected to homes with relatively little bureaucracy, as a balcony solar power plant which renters can install without modifying the building. This seems to have pushed the price down, so there are many 800W kits including panels, an inverter and cables available for under 400 euros.

Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#84

Post by fbdab103 »

avhon1 wrote: post #74
fbdab103 wrote: post #65

Wondering if anyone could help shore up my understanding or point out a resource to get me a better handle on this. Using the solar maps from here[0], you can find the kWh/day/m2 for the US. If I am in a say 5.7 kWh/day/m2 region and I have 1 m2 of a 20% solar efficiency panel, does that mean I would get 1.14 kWh usable out the other end? Or is it 20% * X% horribly lossy conversion factor? If I want to math out 11kWh…

The "System Losses" breakdown shows the various additional factors they are derating the system by. The figures seem reasonable enough, and give an additional loss of 14%. I put in my own address, which is in the 4.0-4.5 kWh/day region, and set the DC system size to 1 kW, which corresponds to 6m2 of panels (courtesy of their rooftop calculator). The NERL website estimated that such a system would yield between 2.45 a…

Super appreciate your reverse calculation. The downstream 14% loss still is an easy enough fudge factor to use for a plausible output number.

Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#85

Post by beanjuice »

refulgentis wrote: post #82
KennyBlanken wrote: post #80

Earlier quoted context omitted.

Solar panels "produced from rare earth minerals" is "under-reported" because they are not made from rare earth minerals , and further: the minor metals they are dependent upon are byproducts of refining base metals, ie there isn't much additional impact from using them; we already make them. I'm not really sure how someone who supposedly worked in solar panel research would think rare earth metals are used in solar p…

This is true: i.e. they use rare metals not rare earth metals . On HN, I hope we can share a correction like that respectfully: after all, they gave good info, except for a one-word slip of the tongue. The critique seems to extend beyond correcting that error, becoming confrontational, questioning motivation and honesty with phrases like "supposedly worked in." and the long bit defending lifespan and enviromental imp…

Thank you for responding, I agree with your points, I did indeed make a mistake.

Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#86

Post by tnel77 »

dr_dshiv wrote: post #29

Here is the graph of exponential installed solar capacity [1]. Like Moore’s law, continuous technological innovation and investment will be required to keep the pace. We just hit 1 terawatt— and doubling time seems to be about every 3 years. So… 1,2,4,8,16,32,64,128,512,1028, 2056 terawatts in 30 years? With 20% capacity, that’s equivalent to >300,000 Million Tons of Oil (MToE) per year. Current global energy consump…

This gives me hope! Thank you for sharing!

Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#88

Post by naasking »

philipkglass wrote: post #70
fbdab103 wrote: post #65

Wondering if anyone could help shore up my understanding or point out a resource to get me a better handle on this. Using the solar maps from here[0], you can find the kWh/day/m2 for the US. If I am in a say 5.7 kWh/day/m2 region and I have 1 m2 of a 20% solar efficiency panel, does that mean I would get 1.14 kWh usable out the other end? Or is it 20% * X% horribly lossy conversion factor? If I want to math out 11kWh…

You'd be able to generate 1.14 kWh at the panel level if you kept the panel pointed directly at the sun throughout the day [1]. This is called "2 axis tracking" and it was sometimes used for solar farms when solar panels were much more expensive. Now that panels are much cheaper, 2 axis tracking has practically vanished from the market. The added expense and mechanical complexity isn't worth it. Single axis tracking,…

> which include a moderate (near room temperature) panel temperature. Panels lose some efficiency as they heat up, which means that they don't perform as well as you might naively expect in the middle of the summer.

This is why vertical solar panels are becoming a thing, the additional cooling benefits increase output up to or beyond the optimal angle to the sun, and the better cooling also prolongs their life.

Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#89

Post by addaon »

dr_dshiv wrote: post #29

Here is the graph of exponential installed solar capacity [1]. Like Moore’s law, continuous technological innovation and investment will be required to keep the pace. We just hit 1 terawatt— and doubling time seems to be about every 3 years. So… 1,2,4,8,16,32,64,128,512,1028, 2056 terawatts in 30 years? With 20% capacity, that’s equivalent to >300,000 Million Tons of Oil (MToE) per year. Current global energy consump…

> So… 1,2,4,8,16,32,64,128,512,1028, 2056 terawatts in 30 years?

What did 256 terawatts ever do to you?

Re: Roll-to-roll fabricated perovskite solar cells under ambient room conditions

#90

Post by gergi137 »

beanjuice wrote: post #53

My two cents having formerly worked in perovskites trying to upscale the process: Perovskites are exciting (or were exciting) because they have a high theoretical efficiency, are relatively simple to prepare, and the "worst" component in them is lead (an incredibly abundant material). The big problem with them is that they are famously horrifically unstable in ambient conditions. Roll-to-roll processing means that yo…

Which rare earth minerals go into solar cells?
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