Organic solar cells set 'remarkable' energy record | Hacker News Reader

Organic solar cells set 'remarkable' energy record

bbc.com

154 pointsjaza55 comments

I hope this makes it into production at some point. I had a lot of hope for the CIGS stuff[1] but they haven't been able to get to the point where they have enough efficiency at at low enough cost to flip them into the mainstream to get mass market economics of scale to work for them.

[1] https://en.wikipedia.org/wiki/Copper_indium_gallium_selenide...

CIGS, like CdTe, has always been limited by material economics. As demand goes up, the world economy’s limited production of these exotic byproducts can’t keep up.

Believe it or don’t, the last time I crunched the numbers, it was the Selenium in CIGS that they’re having the most trouble unlocking more of.

That is surprising, the early 2000's there was a huge uproar over all of the selenium runoff going into the San Francisco bay. At the time I wondered if there was an economic use for selenium and if extracting it from water was economically feasible.

17% efficiency is a very nice result for OPV. I studied OPV tech for my PhD in 2010-2015. The field really started to shrink once perovskite solar cells were discovered and quickly beat out OPV in performance. Many people were predicting that OPV research was dead at that point. Glad to see that some researchers are still pushing hard and making progress!

I'm still holding out hope that these multiphoton singlet fission systems are made to work.

Picked my curiousity, care to elaborate for me and others?

https://www.oe.phy.cam.ac.uk/research/photovoltaics/ultrasin...

I think you mean "piqued".

Must hve been hard for you to do PhD in a shrinking field. Did you follow career in solar cells?

How do plastic solar panels stand up to UV radiation over a long time? UV radiation degrades most plastics.

The two problems historically have been efficiency and endurance. Endurance has been in the range of 2-5 years, so not good. Although I think that’s more to do with reactivity in the presence of oxygen than UV. If UV was the problem you could always just filter it out, albeit at an efficiency cost, whereas total encapsulation is more difficult and expensive.

Don't OPVs still have the problem of breaking down too quickly?

> "I am very positive for OPV, and it may not need five years," he added.

Ah, the magic five years. Whenever you see someone say it's five years away it means they have no idea when, or if it'll come to market.

It's also important to take the fabrication process into account. I'd love OPV to be less polluting (or less costly to recycle waste) than polysilicon or thin-film. Even at 17% efficiency.

17%

And on one of my favorite charts, that red triangle at the very bottom is about to jump substantially up the Y-axis:

https://upload.wikimedia.org/wikipedia/commons/2/28/PVeff%28...

FTA: "Commercial solar photovoltaics usually covert 15-22% of sunlight, with a world record of 26.6% reached in Japan in 2016."

And yet your linked chart shows datapoints >40%. What gives?

Commercial solar photovoltaics typically refer to "standard" silicon solar cells which have efficiency around the 15-22% range. The 40% cells in the graphic are for materials systems that are much too expensive to be commercially viable.

Yep, the very high efficiency cells are typically reserved for highly specialized areas where cost doesn’t matter.. You’ll see Boeing’s name a lot near the top of the efficiency list for the exotic cell types, their lab’s website should clue everyone in to what their main purpose is: https://www.spectrolab.com

They list 31% efficiencies for their cells that can fly today which must be near the limit of commercialization / certification. Still pretty good though, that’s 50% more efficient than a standard panel, and at several $10s of thousands per kg into space, clearly worth it!

28/30% cells are common in spacecraft and have been for more than five years, but they are expensive. A little less than 10k for something like 1 square meter only for the cells wouldn't be crazy.

It looks like Boeing's latest multijunction line ships at 30.7% efficient:

https://www.spectrolab.com/photovoltaics.html#cells_cics

Which seems about right, but what I didn't realize is that they're shipping >40% concentrators too. That's pretty great!

https://www.spectrolab.com/photovoltaics.html#cells_cics

(That last link was supposed to be for the concentrator section at the bottom of that page, but I don't think it's a normal # bookmark)

These cells should be available for everyone and not just the 1%.

These things aren't expensive just for fun. They're usually made of very exotic materials or very difficult to manufacture, hence the prices. They'll go down if they become easier to make.

Although in this case those ultra-expensive cells are being built by Boeing for space use. That no doubt includes a lot of flight certification and similar checks. If you were making a version for domestic use the price could probably be significantly reduced.

That said, they would only make sense in places where space is at a premium so people are willing to pay extra for something a bit smaller. That's not especially common in home use.

This is what NASA could get to power their satellites, at NASA's pricepoint.

Commercial means what you can buy at reasonable prices.

It takes some time from knowing something is possible, experimental technology, like multitouch controlled computers, and companies selling them in the billions, like multitouch being in every Ipad or smartphone.

multijunctiion.

Well, isn't this new device essentially a multijunction organic solar cell? That's what I gathered from the BBC article.

I guess the hope is that they will command less of a relative premium compared to multijunction silicon cells?

Inorganic multijunction devices are very difficult and costly to make, because the materials have to be evaporated into place. Organics in principle can be printed using standard solvents.

Let’s not forget that many thin-film amorphous silicon devices use multiple junctions as well.

The article isn't very good is what.

No. The >40% are "exotic" in some fashion and very expensive compared to what is commercially available. Think of "hero" cells where the best cell from an entire production run is tested or a cell is produced using techniques that are incompatible with mass production. Now, add in tandem (multijunction) on top of that, and you get to >40%.

Light Reflection, which is one of the problem with Solar panel installation in cities areas. You could literally beam light into other buildings windows.

I wonder if Organic Solar Cells fix this?

Or some day where we could produce Windows Glasses that absorb some of the UV and turns it into electricity for cheap. I know we have the tech but it seems still to expensive for now.

In cities, I don't see how light reflection off solar would be worse than the reflection of conventional glass surfaces, which are ubiquitous already and which sometimes cause problems (google "London death ray"). Photovoltaic installations tend to be uniformly oriented, so that concave mirror problems cannot occur.

In the countryside, things are different: you have massive installations close to ground level, often at hillside slopes, and if you happen to drive on a road towards one of those at that special time of day/year when the reflection goes straight into oncoming traffic you are left with staying calm and hoping for the best. Happened to me on an unrestricted stretch of Autobahn, slowing down where everybody else is also blinded would be a very, very bad idea. As I said, stay calm and hope for the best. I could really see a case for building codes to get updated to prevent such things (the position of the sun over the course of the year is perfectly predictable) and maybe even a revival of heliostat installations for sites where this can be an issue.

I don't think light reflection is at all a problem with solar panel installation in city areas. Buildings are already reflective, and mirror surfaces on glass towers have been the fashion for decades. Even if light pollution laws exist, they are only in effect at night, and the usual solution is blinds or curtains rather than blocking the source.

Reflected light is lost energy. As long as a solar panel looks like a mirror, it is not efficient. When you will see a solar panel that is very dark, then it might be efficient. I think this is what the parent poster is referring to.

Solar cells only absorb on specific wavelengths. They also lose efficiency if they get too hot. It actually makes sense to reflect away the wavelengths you can't use to keep the panels cooler.

Solar panels do not look like mirrors. Like the first hit on google images --> https://bloximages.chicago2.vip.townnews.com/wacotrib.com/co...

Not first hit then: https://www.google.com/search?q=solar+panels+in+sun&client=f...:

Are you serious? 1. It depends on the exact search terms used. 2. It is well known that google returns slightly different results depending on various factors such as physical (geo) location of searcher 3. Even your example is shows black panels as the second hit, and an obviously false color image as the first hit.

Hard to admit you were wrong, right?

Only because I am not. Troll.

It's expensive and coloured instead of totally transparent but it indeed exists outside of the lab. They did build a wall out of them in my former campus:

https://en.wikipedia.org/wiki/Dye-sensitized_solar_cell

https://actu.epfl.ch/news/epfl-s-campus-has-the-world-s-firs...

Non-native English speaker here: Is there a word to describe something which is transparent but alters colour?

Tinted?

Translucent is somewhat close to what you're looking for.

Try dichroic if you don’t mean translucent.

I wonder about the endurance of these organic cells aside from their strides in efficiency. I recall hearing a few "exotic" solar cell materials having the issue of being too ephemeral especially for the toxic materials involved despite technically better efficiency in operation and they got beaten out by cheap silicon. The applications of these would be remarkable if they lack additional complications.

The title set up sounds like a lazy scientist joke : technically you can call planting a forest, call them organic solar cells and burn them later for a non-direct electricity solution without doing any research.

Amazing.

I dont understand nearly enough about materials science to grok how you iterate to such a discovery. Does anyone else have intimate knowledge of the grind?

The best description I've read of the iterative process of chemistry development is good old "Ignition!" by John D Clark, on the subject of rocket fuels.

Generally what happens is a simple theoretical model predicts what the most efficient compounds to try are - but not all their properties can be predicted theoretically. So somebody has to try them and find out what all the handling and fabrication difficulties are, then develop solutions for the sub-problems.

(Does anyone have the scihub link to the actual study referenced in the article?)

http://sci-hub.tw/http://science.sciencemag.org/content/earl...

Solar energy is very problematic and for now, isn't going to solve the world's energy problems.

For one thing, it generates energy for just when the sun is shining and no clouds overhead, which aren't usually peak hours. There are other problems as well. https://sciencing.com/future-solar-power-obstacles-problems-...

I'm waiting for Fusion power...

You'll be waiting 10 years for the rest of your life.

Progress!

First, it was always 30 years away, then 15 years, now it's down to 10 years. Not sure how to determine the asymptote, but it'll doubtless happen with the Singularity.

Links:

Why Nuclear Fusion Is Always 30 Years Away http://blogs.discovermagazine.com/crux/2016/03/23/nuclear-fu...

Nuclear fusion is 15 years away from reality, say MIT engineers https://www.thechemicalengineer.com/news/nuclear-fusion-is-1...

There's still the big question mark of "will it be economically viable?" By the time Fusion is ready we might be heavily transitioning to cheaper renewable energy sources and not want to subsidize expensive power.

Very good point. Doubtless though, if it ever achieves technical viability, fusion will have a niche, because not all applications require economic viability. Can't beat the energy density it provides, either. Would be great for outer solar system missions.

Why wait for Fusion when we already have viable fission that can patch the world's energy problems while we continue to develop solutions to its shortcomings?

Public perception has been poisoned with regard to nuclear fission. Changing public perception is expensive.

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