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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

#71

Post by philipkglass »

hinkley wrote: post #66
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…

Do we not have lead free perovskites now?

Tin based perovskites have been studied for almost as long as the lead based ones but they have been less efficient and much less stable. Work continues to increase their efficiency and stability, e.g.:

"Efficient tin-based perovskite solar cells with trans-isomeric fulleropyrrolidine additives" (2024-01-29)

https://www.nature.com/articles/s41566-024-01381-7

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

#72

Post by abathur »

jandrese wrote: post #48
abathur wrote: post #40

Earlier quoted context omitted.

I can't recall ever seeing a plywood fence in North America.

You do see them from time to time in especially rough rural areas. I can remember one that was apparently painted from the "oops" paint section of the local hardware store surrounding a strip club next to a junkyard.

Sure. I don't recall seeing one, but the near-inevitability of this is why I didn't assert they don't exist.

Rarity speaks to how poorly suited the material is for building durable fences and the ~irrelevance of the cost of plywood in this subthread.

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

#73

Post by jandrese »

londons_explore wrote: post #58
ElevenLathe wrote: post #10

Earlier quoted context omitted.

If the materials are cheap enough, we might be able to build them into other stuff that was going to use labor anyway (shingles, asphalt, siding, etc). No idea what the economics of this look like though, and electricians (a pretty expensive form of labor) will need to be involved no matter what, but at least theoretically cheaper cells can also deal with labor costs.

I think future designs of panels might be designed in such a way an electrician isn't required. All foolproof plug'n'play connectors and designed in such a way you cannot plug them in in an unsafe way. You don't call an electrician every time you plug in a hairdryer, and a hairdryer is typically higher voltages and currents than a single panel.

Higher voltage than a single panel, but a string of panels easily hits hundreds of volts. Even worse they can be hard to make safe, since as long as the sun is shining they are generating energy and roof installers don't like working at night.

You can avoid this by using microinverters, but they're a pretty substantial premium on each panel and an added point of failure.

There is lot of tech around solar panels that is being effectively obsoleted by the plummeting costs of the panels themselves. Why bother trying to squeeze out the last few percentage from each panel when it's so much cheaper to just install a couple more panels to make up the difference? This is the big difference between countries like the US where solar installs are still expensive at $3-$6/watt and countries like Australia where home solar installs are under $1/watt.

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

#74

Post by avhon1 »

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 and 6.48 kWh/day, with an annual mean of 4.71 kWh/day.

That works out pretty close to what the map indicates for my region: 4.5 kWh/m2day * 0.2 conversion factor * 0.86 losses factor * 6 m2 of panels = 4.64 kWh/day

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

#75

Post by daemonologist »

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)

It's frustrating. Panels around $0.25/W exist, but it's really difficult to get your hands on them in small quantities as an individual. You can either string together a bunch of tiny eBay specials or drive halfway across the country to find a distributor of the panel you want who's willing to sell to consumers.

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

#76

Post by sandworm101 »

mlyle wrote: post #59
sandworm101 wrote: post #25

Earlier quoted context omitted.

>> other stuff that was going to use labor anyway (shingles, asphalt, siding, etc) No. None of that ever works. Everyone has the "good idea" of cramming PV into some other product thinking that doing so will somehow reduce labor. It never does. Solar shingles are typical. They sound great but in reality require hundreds or thousands of electrical connections all spread over the moving flexible surface that is a woode…

Part of why it doesn't work, though, is that PV is too expensive. If it's cheap enough, you can tolerate failures and poor illumination of the panels for things like fence panels or whatever. I do agree you need big panels to not have excessive labor from connections.

>> If it's cheap enough, you can tolerate failures

But you just can't. When you are using lots of tiny things all connected through each other then you have less tolerance for faults, not more. One bad connector can mean that an entire run of shingles is dark. So even a 1% fault rate, if you have a few hundred connections in each run of shingles, means that basically nothing is connected. Or think of a long fence. One broken bit can mean the entire fence after that break is no longer connected. You're just setting yourself up for a long day of checking connectivity only to have the fence shift again.

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

#77

Post by mlyle »

sandworm101 wrote: post #76
mlyle wrote: post #59

Earlier quoted context omitted.

Part of why it doesn't work, though, is that PV is too expensive. If it's cheap enough, you can tolerate failures and poor illumination of the panels for things like fence panels or whatever. I do agree you need big panels to not have excessive labor from connections.

>> If it's cheap enough, you can tolerate failures But you just can't. When you are using lots of tiny things all connected through each other then you have less tolerance for faults, not more. One bad connector can mean that an entire run of shingles is dark. So even a 1% fault rate, if you have a few hundred connections in each run of shingles, means that basically nothing is connected. Or think of a long fence. On…

Most of what you say was anticipated by the comment you replied to:

> > I do agree you need big panels to not have excessive labor from connections.

> You're just setting yourself up for a long day of checking connectivity only to have the fence shift again.

If only we had ways to make long runs of wiring relatively reliable.

My point is: there's second order effects: expensive panels need to have as high of a capacity factor as possible; high capacity factor constrains installations and increases other costs. If you cut 2/3rds of the cost of the panel away, other costs decrease, too, and more types of installation become reasonable.

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

#78

Post by chrisbrandow »

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.

if the substrate really can remain even a little bit flexible however, this opens up entirely new deployment opportunities.

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

#79

Post by chrisbrandow »

myself248 wrote: post #20

Ovonics was doing roll-to-roll solar cells in the 1980s, were they not? This is exciting if the technology scales better or something, but I can't help feeling that we've stagnated a bit.

costs of solar panels of all sorts have dropped 100 fold in that time. I'm not sure I'd call that stagnation.

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

#80

Post by KennyBlanken »

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 panel construction.

Solar panels have decades-long lifespans (their rated lifespan is based on when they drop below 80% efficiency, not when they become useless), there's a growing recycling chain to sell complete aged panels to other markets (typically underdeveloped nations where daily equivalent hours of solar are very high and land is plentiful so efficiency doesn't matter), and the panels themselves are highly recyclable for the materials to make new panels.

Ever notice how the people 'concerned' about the environmental impact of mining rare earth minerals, which go into durable goods that are highly recyclable/recoverable, don't seem to have a problem with oil drilling, fracking, coal strip mining, etc - for something that is usable once, maybe twice?

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