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NiceWayToDoIT

What is:

Power output per m2?

Durability (life span)?

Production cost?

At least theoretical ...

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Non of that can be answered just yet. This is basic research in its earliest stages.

It can't even be answered theoretically, because the researchers are in the process of developing the theory that could answer these questions.

So far they only made an observation and need to go on from there.

From the underlying paper[1], I found this excerpt:

“The photocurrent or the short-circuit current density (JSC) extracted from BTO is around 0.415 μA/cm2. … The JSC value from SBC555 is around 11.03 μA/cm2 and is about 25 times higher than measured in BTO. The open-circuit voltage (VOC) in the case of BTO was found to be around −0.007 V, as opposed to −0.058 V in SBC555.”

Here, BTO is the existing material and SBC555 is the new material from the paper. Multiplying JSC by VOC to get power density , we see that BTO yields 2.9 nW/cm^2, while SBC555 yields 639.74 nW/cm^2.

For reference, according to [2], we have that “typical external parameters of a crystalline silicon solar cell as shown are; Jsc ≈ 35 mA/cm2, Voc up to 0.65 V.” Notice the unit difference of mA/cm^2 here vs uA/cm^2 above. Multiplying these parameters yields 22,750,000 nW/cm^2. So we see that these cells are still approximately 100,000x worse at producing power than the current crystalline silicon cells.

[1] https://advances.sciencemag.org/content/7/23/eabe4206

[2] https://ocw.tudelft.nl/wp-content/uploads/solar_energy_secti...

Thank you sir!

This type of cheeky criticism is probably fair when you have a startup claiming crazy numbers with no prototype, but this is reporting on a paper from a research institution. No need for snark.

criticism, snark ?!

What are you talking about?! All I am trying to get some numbers, if anyone has them, but it seems amount of unhelpful comments begins to be overwhelming on HN.

Seems like some people are unable to handle actual questions on anything that appears challenging and want to dismiss as being hyper critical and snarky for not just drinking the kool-aid.

There was no snarky tone-of-voice in your reply when I read it. Maybe cultural differences? Please, kindly inform me of the output of the power output per m2? Also, is there any information available regarding the durability (lifespan) of the product? Who's got time to be that formal on something as an internet forum? I read topic, now here's some questions I have is perfectly fine. Some people possibly just need to get thicker skins and realize that not everyone out there is trying to be an asshole and just stop reading things in that manner.

Honestly, I do not know how much technical my question can be, there is no tone, there is 14 words in total. I was googling and I could not find anything useful so I hoped I could get some answer from some technical person (material science/physic person). In my mind finding those number is the first thing I would do on the test bench, they give you prospect of technology some kind a range you would attract investors. You would have test sample 1X1cm you shine that amount of light and you get output. And then you know this is feasible and can help in future or not... simple as that. Instead I am getting some kind responses like I am talking with emotional teenagers tripping on some cry baby drugs... for heaven sake ... (yes that last is emotional response, I mean seriously what is going on with HN lately it used to be place with tech guys talking tech ...)

I suppose the tone could come exactly from the brevity. Imagine stepping up to a bakery and hearing “what?” instead of “how can I help you today dear gentleperson?”.

Which one would you find more snarky?

Even if the bakery employee yelled "What?" at me, I would not hear snark in that. I would probably hear rude, but not snark. I would also be a little less surprised if it was a very busy place and the employee was visibly harried by the commotion. Or if I was just in any store in NYC.

There's a difference between terse and to the point vs being rude. It's not the terse response's fault the recipient cannot tell the difference.

Also, are we using snark as a synonym for rude nowadays? I'm going to need to update my definitions as I was always understanding snark to be sarcasm. I just want to be using the same words as everyone else on the internet so I don't offend. (that was snark).

Edit: actually, if I went to a store and someone asked "how can I help you today dear gentleperson?", I would immediately assume they themselves were being snarky. That's like saying "bless your heart". It's just dripping with snark.

I always assigned “rude sarcasm” to snark but apparently it is just sarcasm.

FWIW, I didn't detect any snark in your words either. Perhaps brevity was mistaken for snark?

For the rest of us that read no snark, please enlighten us into what words/phrasing led to your reading of snark in the parent's post. Curious minds would like to know answers to the actual questions posed by the parent, but also to what sensitivities are being upset by asking those questions.

They don't cite power output, but cite current output: 17 mA / cm² under full sun, pretty impressive if you ask me.

The key promise of this approach is "more efficient that silicon can even theoretically be". Overcoming the Shockley limit is the key finding.

Thank you, is there any way we could find out what is probable life span, is it more durable (hailing/dust/corrosion) or less than silicon crystal? From time to time it would be nice if we had AMA on HN like on Reddit for the research team.

Also mA does not says much if we do not have voltage, and I am not sure what full sun means as in Africa full sun can mean 4.5 and 6.5kWh per m2 while in Europe we can get between 1 and 2.5kWh per m2 or radiation.

The article tells you the answer to your question. Search for "1,000".

Edit: Apologies, I misread the parent's question. I thought they were saying "1,000 what?". Sorry about the unhelpful answer.

No it doesn't. The 1000x factor refers to the photo-response of the material, not power output, not cost to produce, not durability.

All these are properties of a (prototype-)product, while this research is basic research and didn't create any prototypes. The researchers measured the photo-response by shining laser light onto a sample, they didn't build a panel and measured the power output.

Not 1000x net output since we are in what now, 10-20% efficiency with current available cell technology? That would not make sense.

From one of the comments on the article:

  Ryan Kennedy
  August 6, 2021 at 1:46 am
  Our apologies for not making this clear. The photovoltaic 
  effect was increased by 1000 times compared to previous 
  output achieved from cells made of ferroelectric crystals, 
  not from prevailing solar cells made of silicon or other 
  conventional materials.

Ok, now we just need to know how ferroelectric crystals compare to conventional solar cells to find out what this "1000x" really means...

i would guess that they are about 1000x worse than conventional silicon

Or much worse yet, otherwise the authors could have used clear language.

Yes, it would be extremely helpful if we knew how they compared to what people are able to purchase today.

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