[HN Gopher] Panel with photovoltaic material layered on silicon ...
___________________________________________________________________
Panel with photovoltaic material layered on silicon hits 33%
efficiencies
Author : mfiguiere
Score : 79 points
Date : 2023-07-07 18:06 UTC (1 days ago)
(HTM) web link (arstechnica.com)
(TXT) w3m dump (arstechnica.com)
| throwawaymaths wrote:
| We should all take a moment and appreciate that plants are pegged
| to (IIRC) 10-15% theoretical max efficiency, and that's just in
| photocapture, it's even worse when you factor in chemical
| inefficies in storage and conversion of sugars back to usable atp
| (which it must do to use the energy)
| nightfly wrote:
| Plants also are able to make more of themselves from dirt out
| of pennies worth of matterial
| ben_w wrote:
| Mostly they make themselves out of air, which is even better.
|
| The dirt has necessary trace elements, but the carbon? That's
| all from CO2.
| [deleted]
| throwawaymaths wrote:
| Oh man you've never cared for trees/plants have you. Some
| of em (most often the ones you "want") are total crybabies
| over those "trace elements".
|
| You can't have DNA without phosphorus, for example, and
| many plants can't make nitrogen from air. Don't get me
| started on magnesium (needed for chlorophyll)
| chewbacha wrote:
| I understand what you mean but the vast majority of their
| structure is carbon based and that comes from gaseous
| CO2. Can't survive without the dirt but can't get big
| without CO2
| TaylorAlexander wrote:
| I want to suggest re-reading their comment. "mostly they
| make themselves from air" and "dirt has necessary trace
| elements" are both 100% factually correct. The word
| "necessary" covers what you are saying in your comment.
| There's no need to suggest they haven't raised plants
| when what they said is literally correct.
| sbierwagen wrote:
| https://nutrients.ifas.ufl.edu/nutrient_pages/bsfpages/Es
| sen... element %, dry wt.
| oxygen 45 carbon 44 hydrogen
| 6.3 nitrogen 1.3 silicon 1.2
| potassium 0.9 calcium 0.25
| phosphorus 0.16 magnesium 0.16 sulfur
| 0.15 chlorine 0.15 aluminum 0.11
| sodium 0.03 iron 0.009
| manganese 0.006 zinc 0.003 boron
| 0.001 copper 0.0005 molybdenum
| 0.0001
|
| Just CHON is 96.6% of plant mass. Adding silicon,
| potassium and calcium brings it up to 98.95%
| kccqzy wrote:
| What's your point? If I only allow you to eat C, H, O, N
| and their compounds, will you survive?
| goldenkey wrote:
| In the same vein, most of our energy comes from oxygen, not
| the food we eat :-)
|
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6379287/
| detourdog wrote:
| Yikes sounds like decomposition.
| londons_explore wrote:
| It's kinda surprising that plant efficiency is so low,
| considering the absolutely massive number of plants and the
| hundreds of millions of years of competitive evolution to
| collect as much energy from sunlight as possible.
| api wrote:
| Other limiting resources dominate over energy availability
| for plants.
| nightfly wrote:
| I think they just don't have any need/pressure to be more
| efficient than that
| londons_explore wrote:
| If you can collect more carbon, you can grow faster,
| letting you put big leaves to collect more light and
| overshadow and kill all the plants below you.
|
| Being a plant is, locally, a winner-takes-all market.
| londons_explore wrote:
| > plants are pegged to (IIRC) 10-15% theoretical max efficiency
|
| I suspect this is soon to change.... With CO2 levels around 280
| ppm, the biggest challenge for many plants is finding a carbon
| atom - in fact, many plants grow just as fast under just 10%
| brightness sunlight.
|
| Now that CO2 is up at 420 ppm, it's far easier to find carbon,
| so now the evolutionary race will be on to collect more
| sunlight and grow faster. And plants have done this before, ~20
| million years ago, so somewhere there are probably some
| recessive genes just waiting for their moment to shine again,
| and natural selection will make them spread like wildfire.
| ink_13 wrote:
| "Soon" on an evolutionary scale could still mean hundreds if
| not thousands of years.
|
| For example, wood is a great food resource for fungi, but it
| took millions of years for wood-eating fungi to evolve after
| wood.
| c_crank wrote:
| It's good news for maize. That's a very carbon hungry crop.
| c2h5oh wrote:
| If it was just CO2 levels going up then maybe. The problem is
| that temperatures are going up too, so gas solubility is
| going down. This means that C4 or CAM photosynthesis plants
| might get an edge over C3 on a larger area.
| ChatGTP wrote:
| We'd have to assume that due to the greenhouse effect , the
| earth was also hotter then ?
| timmg wrote:
| Even without any genetic adaptations (probably?) the world is
| "greening" due to increased CO2:
| https://www.nasa.gov/feature/goddard/2016/carbon-dioxide-
| fer...
| mehdix wrote:
| It'd be in user's best interest but not corporation's best
| interest.
| syntaxing wrote:
| Does 33% efficiency means it can generate 3.3kW per m^2?!
| philipkglass wrote:
| 330 watts. Sunlight is about 1000 watts per square meter at
| noon on a clear day.
| hesdeadjim wrote:
| Anyone know what the state of the art is/will be for panel
| lifetimes? Efficiency is great, but I'd sacrifice some if it
| meant 50+ year lifetimes of 85%+ peak output.
| greenthrow wrote:
| They essentially last 50+ years now, and have always, barring
| damage. State of the art panels today warranty 90%+ output
| after 25 years. So they probably aren't far off what you're
| asking for at 50. They keep getting better and cheaper every
| year.
| jeffbee wrote:
| NREL's latest data is summarized here:
|
| https://www.nrel.gov/docs/fy22osti/81172.pdf#page=5
|
| Some types of panels have increased capacity after being in
| the field for years. Degradation is not a significant
| economic concern at this stage of the process.
| abdullahkhalids wrote:
| I see degradation numbers between -0.1%/year and
| -1.1%/year.
|
| This translates to about
|
| * 0.999^25 = 97.5% to 0.989^25 = 75.8% output after 25
| years.
|
| * 0.999^50 = 95% to 0.989^50 = 57.5% output after 50 years.
| Retric wrote:
| Data I've see doesn't show output dropping continuously
| at a constant rate. Also some panels did show modest
| improvement for a few years.
| londons_explore wrote:
| > modest improvement for a few years.
|
| Many regions of the world are getting dryer. You might
| just be seeing a global warming side effect as there is
| less cloud cover.
| londons_explore wrote:
| It would be good to break the figures down between:
|
| * The actual silicon is degrading
|
| * The cover glass is getting
| dirty/frosted/delaminating/optical adhesive is no longer
| clear
|
| * Electrical failure of a whole cell - for example it is
| cracked, yet the panel still appears to work due to the
| bypass diodes removing a whole cell from the circuit.
|
| Sure - from the users point of view it doesn't matter,
| but from an engineering point of view, the cause of
| failure gives some clues how to prevent it.
| philipkglass wrote:
| This is true for panels on the market now, and most of those
| produced in the past. The 33% tandem systems reported on by
| Ars Technica see severe efficiency degradation after just a
| few hundred hours of full-power operation, so that's
| something that needs to be solved before perovskite-on-
| silicon tandem systems enter mass production.
| larsiusprime wrote:
| What about hail damage? That's the main concern holding me
| back, but is this something already being addressed?
| abdullahkhalids wrote:
| You can always put more/stronger glass on top to protect
| them more.
|
| But I would bet it is cheaper to buy insurance for such
| infrequent events.
| jackmott42 wrote:
| Consumer panels on homes have hail protection since
| forever.
| ben_w wrote:
| That sounds like you want armoured panels; As I understand
| it, the degradation being discussed here is from the light
| itself.
| greenthrow wrote:
| Most panel warranties cover hail up to like 1" diameter.
| So, pretty sizable. Beyond that, you need insurance.
| goldenkey wrote:
| Is it possible to put some translucent protective material
| that doesn't block the frequencies the panels absorb?
| jackmott42 wrote:
| yes, they use this new tech called glass.
| epolanski wrote:
| I have worked as a solar scientist researcher for some time,
| have coauthored 3 papers in Michael Graetzel[1]'s laboratory
| and I have some experience in both Graetzel cells and
| perovskite solutions like the one mentioned in this article.
|
| Long story short: scientific researchers, especially those in
| well funded laboratories are incentivized by the wrong metrics
| (in all fields, not unique to solar) and in this field the only
| metric that matters is efficiency. It doesn't matter if your
| cell decays by 50% in a day, it reached some great potential in
| a new way, here's the way for a high impact publication.
|
| Want to work on the other problem though? Lifetime, resiliency?
| Cheap and affordable and non-toxic materials?
|
| Good luck getting proper funding and exposure. Why? Because
| scientific papers are a closed mafia, where a set of the most
| influential scientists (doesn't matter how many scientists the
| planet has, the moment you start entering a niche the number of
| people is very low) in their field review the submitted papers.
| Don't have high efficiency or you're not breaking science?
| Forget a high-impact journal. You're back at B-tier, C-tier
| papers, but those won't get you funding and status. Not great
| for your career.
|
| So what do you do? You play fool and focus your efforts and
| many many millions of euros to get the next perovskite cell
| that can reach high 20%s with some twist at least or go for the
| 30%+ ones.
|
| Just to express how sad and toxic the world of scientific
| research is (not even mentioning the insane amount of fake data
| that gets published every day, the politics, etc): instead of
| being a researcher I now prefer being a web developer writing
| forms list and tables.
|
| [1] https://en.wikipedia.org/wiki/Michael_Gr%C3%A4tzel
| casparvitch wrote:
| I disagree that science has the wrong incentives. The place
| for science is to chase new (e.g.) physics, not build
| something useful.
|
| As a society we have decided that (e.g.) physics should/shall
| solve our problems with better technology. But that is not
| what pure academic science is about, or what pure academic
| scientists care about.
|
| You want to iteratively improve technologies? Give more
| funding to proper engineers, not physicists/chemists, even if
| they're sometimes in the 'school of electrical engineering'.
| ScoobleDoodle wrote:
| Lifetime, resiliency, non-toxic structure are different
| dimensions to efficiency and there are likely trade offs
| between them. Those all can involve what you call "new
| physics" but parent points out only one gets funding:
| efficiency. Which parent also points out is suboptimal for
| society.
| jackmott42 wrote:
| Parent claimed only one gets funding, but that is wrong.
| Industry, capitalist companies work on the other stuff
| all the time. Parent is likely wrong about researchers
| not getting funding for that other stuff also, parent
| likely had trouble getting funding himself due to bad
| attitude and blames it on other factors.
| epolanski wrote:
| I like how you decided to trash years of my life and
| experience and made up a scenario where I'm motivated by
| envy or failure (and even faulty of bad attitude) behind
| your keyboard because my experience doesn't fit your
| views.
|
| If you've been in this field, I'll gladly listen to your
| experience.
| philipkglass wrote:
| Crystalline silicon cells are already cheap, non-toxic, and
| long-lived. So it makes sense that most researchers are
| looking for higher efficiency. Back when purified silicon
| prices spiked around 2007-2008 there were a lot of efforts
| looking into more affordable (if less efficient) thin film
| based materials, but those fizzled out as wafered silicon got
| cheap again and kept widening the efficiency gap over e.g.
| amorphous silicon.
|
| Since there's also a much bigger solar industry today than in
| 2007, you also see more practically-minded research coming
| out of corporate centers (e.g. Longi, Oxford PV, GCL System
| Integration, and others working on perovskite cells and
| perovskite-silicon tandems). Since they care about shipping
| working products, they are focused on solving lifetime and
| durability issues. Of course since this research can give a
| big commercial edge as single junction silicon reaches its
| efficiency limits, you'll also only see the really promising
| work published after it is patented.
| epolanski wrote:
| Silicon is far from non-toxic to produce (requires insane
| amount of heat and chemicals to be purified) and dispose.
| fsh wrote:
| Could you list some of these chemicals? A quick google
| search only came up with pretty benign standard
| industrial chemicals. Disposal is a complete non-issue
| since the cells are inert and non-toxic (though recycling
| probably makes more sense than dumping them somewhere).
| jeffbee wrote:
| All these factors are reflected in the price and yet
| ordinary silicon PV panels are still dominating the
| market.
| ZeroGravitas wrote:
| I'm the opposite, I'd trade some of the current longevity, for
| ever increasing efficiency.
|
| Some research suggests you should replace all solar panels
| every 17 years because the tech will have advanced enough to
| make it worthwile.
| walrus01 wrote:
| There are very reputable manufacturers now that warranty on a
| sliding scale over time to be 84% of original STC watt rating
| at 25 years.
___________________________________________________________________
(page generated 2023-07-08 23:00 UTC)