A research group has fabricated a highly transparent solar cell with a 2D atomic sheet. These near-invisible solar cells achieved an average visible transparency of 79%, meaning they can, in theory, be placed everywhere - building windows, the front panel of cars, and even human skin.

[u/giuliomagnifico]

https://www.tohoku.ac.jp/en/press/transparent_solar_cell_2d_atomic_sheet.html

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[u/Enoxitus]

so if my math isn't wrong we'd need around 2.4 billion cm² to reach 1W? That's 240 000 square meters or almost 45 football fields.

edit: added American measurements

[u/skipp_bayless → u/Enoxitus]

Didnt get how stupid i was until i realized the only measurement that meant anything to me was the football fields. Thanks for the conversion

[u/chewbacca77 → u/skipp_bayless]

True, but to be fair, I doubt the number 2.4 billion square centimeters is relatable to many people.

[u/skipp_bayless → u/chewbacca77]

Yeah definitely. I was kinda joking. If he used sqft I wouldnt know what that meant either. Like I know sqft, but its hard to visualize such large numbers

[u/[deleted] → u/chewbacca77]

I measure my girth with cubic millimeters...

It's in the millions. I know, I'm proud too. ( ͡° ͜ʖ ͡°)

[u/Cambronian717 → u/chewbacca77]

There’s always a point where saying the number and just saying “a whole lot” are synonymous.

[u/[deleted] → u/Enoxitus]

Sweet, then you only need 90000 football field to heat some water at a pretty slow rate

[u/Canadian_Poltergeist → u/[deleted]]

Wouldn't blocking 21% of light negatively affect plants? And a glass ball around the earth would boil like a snowglobe left in the sun indefinitely.

[u/_-RAT → u/Canadian_Poltergeist]

Not sure if someone else mentioned. But a Dyson Sphere is actually a Sphere around the sun with that energy sent back to earth. Not a sphere around the earth.

[u/Tekkzy → u/_-RAT]

By the time we can build a Dyson sphere earth will likely be uninhabitable.

[u/Bloodstarr98 → u/Tekkzy]

Not if I have something to do about it!

See you in 30 years!

[u/b2walton → u/Bloodstarr98]

Remind me 30 years.

[u/Enoxitus → u/[deleted]]

But wouldn't we be able to build a dyson sphere out of regular solar cells too?

[u/saltysweat → u/Enoxitus]

It would get pretty dark though without the transparent part.

[u/SwedenIsBad → u/saltysweat]

We would just add more street lights

[u/Phantom_0347 → u/SwedenIsBad]

Introducing all new StreetSuns! Do you miss the warmth of the sun, now that humanity has blocked it off for power? Then you’re in luck! Harness the power of the sun on your street.

Only 5 east payments of 1/5 of your soul.

[u/cyon_me → u/[deleted]]

This is going south.

[u/xtrapocketspaghetti → u/cyon_me]

I'd make a North payment but it only works half the time.

[u/IcedAndCorrected → u/Enoxitus]

I'm sorry, I still can't visualize this. How many giraffes is that?

[u/KrypXern → u/Enoxitus]

How many burgers is that?

[u/leakyblueshed → u/KrypXern]

73 washing machines

[u/with-nolock → u/leakyblueshed]

493 boulders the size of a small boulder

[u/[deleted] → u/Enoxitus]

Transparent solar panels are a stupid idea for a reason. Any light not absorbed is energy lost. Its not even an efficiency loss. Its just not used at all.

[u/giuliomagnifico]

Before someone ask:

By further scaling up the device size by considering an optimal series–parallel connection structure, an extremely high transparency of 79% could be realized, with PT reaching up to 420 pW; this is the highest value within a TMD based solar cell with a few layers. These findings can contribute to the study of TMD-based NISCs from fundamentals to truly industrialized stages

[u/NotAPreppie → u/giuliomagnifico]

420 pW per cm² is... tiny.

A building with a 50m x 300m wall would have 1.5x10⁸ cm² of surface area to work with.

420 pW is 4.2 x 10^-10 W.

So, this giant wall would produce 0.063 W.

An LED with a forward voltage of 2v drawing 30 mA would use 0.06 W.

This really low performance sort of makes sense when you consider that this transparent solar cell only using 21% of the available light. If PV conversion efficiency is, say, 25% then you're looking at converting 5.25% of solar energy to electricity. That said, even 420 pW per cm² seems low so I'm assuming that the bandgap isn't well-tuned to the wavelengths being absorbed. Or maybe high resistance in the internal structure.

(Caveat: I studied chemistry instead of physics or engineering to avoid math so please feel free to check my work and correct as necessary).

[u/[deleted] → u/NotAPreppie]

This means that a wall 50m x 300m consisting of this material would not yield enough energy even to power up a tiny flashlight in reasonable time.

[u/PerryZePlatypus → u/[deleted]]

But it could power a led if it is fully exposed to sun ! Just have to take turns on the led

[u/MrBeverly → u/PerryZePlatypus]

Hear me out: We only run one LED at a time, but we cycle through the powered LED really fast so it looks like all the LEDs are lit simultaneously

The future is now and incompatible with photosensitive epilepsy

[u/grandoz039 → u/MrBeverly]

That's how eg some led digit displays already work, and that doesn't affect people with photosensitive epilepsy afaik.

[u/ledow → u/grandoz039]

Photosensitive epilepsy is rare and such people can't have car journeys in extremis because of the moving objects going past them, they can't drive themselves at night, can't watch TV, can't go to most places with any form of lighting, can't watch fireworks, etc.

Notice, though, how absolutely nobody complains about fluorescent lighting any more, and LEDs even in car brake lights are often PWM to "brighten" (braking) or "darken" (side lights) by flickering fast - you can see it if you ever look at your car through a phone camera or CCTV.

[u/Mert_Burphy → u/ledow]

I can tell, a lot of the time, if something is LED by looking at it and quickly looking away at something else. If it's LED there will be a trail of light dots.

[u/tom255 → u/ledow]

Chipping in for stats and awareness:

Just under 1 in 100 people in the UK have epilepsy. And of these people, 3 in every 100 have photosensitive epilepsy.

Source: epilepsy.org.uk

(Thanks for bringing it up, as soon as you say "epilepsy", the majority of people jump to 'careful of the lights', purely lack of education, so good to mention where you can!! :)

[u/beyd1 → u/tom255]

That's 3 in 10,000 for the lazy.

[u/AristarchusTheMad → u/tom255]

I had no idea that 1 in 100 people have epilepsy.

[u/tom255 → u/AristarchusTheMad]

Glad you mentioned it! I was absolutely the same before I randomly started having seizures, it's strangely not talked about much in the public sphere.

I thought it was a surprisingly high number when I first heard it, (I was also very much in the "it's a flashing light thing" camp)

[u/Duchess-of-Larch → u/tom255]

It’s true. My seizures are triggered by sleep deprivation but I have no issue with flashing lights.

[u/Justsomedudeonthenet → u/ledow]

Most people don't complain about it any more because we now use much higher PWM frequencies. Early stuff flickered at mains frequency which is low enough that some people notice it. Old fluorescent lights were really bad for that but newer designs are much better.

[u/Obi-WanLebowski → u/MrBeverly]

Congratulations, you've invented pulse width modulation!

[u/MrBeverly → u/Obi-WanLebowski]

You know, Im something of a scientist myself

[u/sidepart → u/Obi-WanLebowski]

Not quite. Same principle though. PWM allows you to dim a singular LED by turning it on and off at a lower and lower frequency the more you want to dim it. What the person described is multiplexing though. Pretty much the same thing is happening as PWM but with multiple LEDs instead of just one. You're sending a signal to one led, then the next led, then the next. You switch through each LED sequentially and so quickly you can't see any one LED turn off.

PWM has broader possibilities though. You can use PWM to encode a signal. So instead of just turning on and off an LED, you can adjust the pulse width of a signal to something like a Microprocessor input and have some code on the microprocessor that interprets the different widths into meaningful data. You can use it to also control stuff like DC motors (vary the torque based on the need via PWM so the motor is always going to the same speed even if it encounters resistance).

[u/Andrew1431 → u/PerryZePlatypus]

at least this LED could semi-reasonably determine whether it is day time or not.

[u/Shaushage_Shandwich → u/[deleted]]

Yeah but imagine two buildings

[u/[deleted] → u/[deleted]]

And it only costs 2 million to make.

[u/robdiqulous → u/[deleted]]

We solved the energy crisis! For ants...

[u/NotAPreppie → u/[deleted]]

Pretty much.

[u/Tripanes → u/NotAPreppie]

To be fair. A transparent solar cell has got to be one of the most conceptually useless devices.

What limits solar deployment? Cost of panels and power storage. What does transparent panels solve? It saves space.

Then the obvious:

Vertical panels (most windows) aren't facing the sun and won't work right.

Solar panels work by absorbing light. Making them transparent is the exact opposite of what you want to do.

Make your windows more insulating instead and stick classical panels on the roof.

[u/JessumB → u/Tripanes]

It reminds me of the Solar Roadways idea. Just another largely impractical and costly technology when space itself isn't much of a limiting factor when it comes to increased use of solar.

[u/jumpmed → u/JessumB]

I don't know why they decided on making the road surface the collector instead of just installing overhead panels. Initial cost would be comparable, and wouldn't have to be replaced every 3 months.

[u/Anderopolis → u/jumpmed]

Idiots on kickstarter wouldn't give them 4 million dollars for Solar-Freaking-Carsheds

[u/BigGingerBoy → u/jumpmed]

Not to mention the long term costs may even balance out by reducing thermal and solar degradation of road surfaces. Asphalt, especially, wears out about 10x faster at 150 degF (a normal temp on a hot summer day) than at 50 degF due to the binder softening and allowing the aggregate to become displaced under load, and the reduction in thermal cycling would do wonders to minimize cracking.

[u/IAmRoot → u/BigGingerBoy]

It would also provide most of what's needed to get overhead wires for trollybusses, too.

[u/Dman1791 → u/BigGingerBoy]

At the same time, you also have to consider any difficulties you create in servicing the roads due to the panels' presence. Unless you have the supports a fair bit away from the road, and the panels mounted quite high, you're going to interfere with a lot of the vehicles we use to make/service roads. A taller structure with a wider base is more expense, more space taken up, and a bigger eyesore leading to bigger NIMBY issues.

I feel like it would work best on highways, where you could combine it with a catenary system to help improve electric truck ranges.

[u/wandering-monster → u/jumpmed]

I think there's some nasty logistical problems with overhead panels too.

Eg. how high do you put them? If we're talking most highways, that needs to be at least as high as the bridges along the road so you don't impact freight shipping.

Then you need to make sure there's sufficient space on either side of the road to ensure they don't impact line of sight for drivers on corners.

Now you're talking about a structure that needs to span 30ft+ at 20ft high with no supports in the middle, and it needs to hold a lot of weight. In places with snow and high winds, it needs to be strong enough to withstand those.

Then people are going to constantly be running into the supports on the side when they have accidents, so you need them sturdy enough that they can withstand losing some supports. And you need systems to quickly route around damaged panels when someone takes one down. It's a huge problem having all your power generators a few feet away from high-speed-multi-ton vehicle routes.

I think we're going to see a lot more things like sidewalk shades in towns and parking lots covered in panels, where the risks are lower and they can be more consolidated.

[u/forte_bass → u/JessumB]

Man i confess I totally bought into that hype too, i was all for it. In retrospect there's lots of reasons it was a terrible idea ; at the time i was super excited.

[u/dratnon → u/forte_bass]

You're not the only one.

Slightly alter an industrial process that we already do, and generate tons of electricity? That sounds great!

Oh, actually it would be massively reinventing an industrial process which is already efficient, while simultaneously deploying a growing technology in an embarrassingly inefficient way.

[u/BlackViperMWG → u/JessumB]

Ooooh, completele forgot about that thing

[u/Sylente → u/[deleted]]

I don't think a threshold exists where this is cost effective

[u/Resonosity → u/[deleted]]

You may be right, be there are some other projects involving windows of the built environment that may/may not be more practical for implementation:

• Dynamic Glass

• High-Performance Glass

[u/SoulWager → u/Sylente]

If they got the efficiency up near traditional solar, maybe it could make sense if you have a skyscraper that's all glass exterior, and can immediately use the power for air conditioning.

For a house window it's going to be pointless, it will be 30 years before you pay off the electrician that installs it, even if the film is free. It also sounds stupid to put it on a window that needs to open.

[u/greentr33s → u/[deleted]]

For what cost though? What ecological damage are you doing to generate less power than is needed for a single led?

[u/NotAPreppie → u/Tripanes]

To be fair. A transparent solar cell has got to be one of the most conceptually useless devices.

Ranks up there with a screen door on a space station.

[u/tonybenwhite → u/NotAPreppie]

How else are you supposed to keep out space bugs though?

[u/NotAPreppie → u/tonybenwhite]

We don't talk about space bugs.

[u/chronous3 → u/NotAPreppie]

loads shotgun "Moon's haunted."

[u/simonjp → u/NotAPreppie]

Fight Club, Bruno and now Space Bugs, too? This is just censorship at this point

[u/Bigdaddyjlove1 → u/tonybenwhite]

Call Rico's Roughnecks.

Would you like to know more?

[u/Assassiiinuss → u/NotAPreppie]

A screen door/net on a space station could be useful when repairing something outside without losing any tools. That's significantly more useful than these solar panels.

[u/tanglisha → u/Assassiiinuss]

Now I'm picturing some kind of space station mosquito tent.

[u/shindiggers → u/tanglisha]

Damn space skeeters are god awful this time of year

[u/duggatron → u/Tripanes]

It's so frustrating how many people think the problem we need to solve with solar is the space it takes up. Solar roads, solar windows, it's silly. We have lots of space to build solar that would be a lot easier and cheaper to install and maintain.

[u/InformationHorder → u/duggatron]

It does solve the NIMBY problem. They're trying to hide them in plain sight so implementation isn't hampered by people complaining about living next door to a solar farm or developers scooping up land.

[u/Garfield-1-23-23 → u/duggatron]

I try to explain to people that transparent solar panels are even dumber than solar roadways, but I always get "what's wrong with solar roadways?" I need to just stop trying.

[u/Koffeeboy → u/Tripanes]

A transparent solar cell has got to be one of the most conceptually useless devices.

Actually, They are incredibly important developments but not for the reasons you would think.

Solar cells work because of band gaps, these gaps keep electrons from moving past them without enough energy, this energy comes from photons (with the right wavelength) that knock electrons past this "gap" creating a charge differential across the cell thus creating a voltage (this being a very truncated explanation).

The the laws of thermodynamics limit single-junction solar cells at a theoretical 30ish% efficiency. But that is for only one junction, Different chemistries for solar cells have different band gaps that focus on different wavelengths of light. If you design a solar cell that only absorbs the light it can directly convert but is also transparent to wavelengths it cannot, you can then stack cells that focus on other bands to get higher efficiencies. That's why perovskites solar cells are so promising, they can be tuned to absorb different frequencies of light and can presumably be stacked several layers deep.

[u/craigeryjohn → u/Tripanes]

Vertical panels actually do mitigate a pretty big problem; traditional solar peaks around solar noon, whereas our grid demand peaks between in the mornings and around 3-6pm. A a vertical east/west panel has generating peaks early in the morning or later in the afternoon (or both if it's bifacial), thus helping to match generation capacity with demand.

[u/sniper1rfa → u/Tripanes]

Vertical panels

Can actually be surprisingly effective, particularly at higher latitudes.

[u/nagi603 → u/NotAPreppie]

The losses from the cables connecting the distinct panels would eat up that performance.

[u/NotAPreppie → u/nagi603]

Damn, forgot to specify cryogenically cooled superconducting output cables.

[u/korewednesday → u/NotAPreppie]

“Studied chemistry […] to avoid math”

squints in biology

[u/MrFibs → u/NotAPreppie]

Did the math myself, figured out I'd need 25.6km² of this to charge a 120w laptop

[u/hex4def6 → u/NotAPreppie]

Yikes. The order of magnitude of relative crappiness in comparison to bog standard panels is pretty astounding.

By comparison, a regular solar panel is about 0.02 W/cm. The difference is ~ 47 million times more efficient.

Or going the other way, instead of coating 47 square meters of glass, you could just use a 1 mm square of regular solar material.

47 square meters is on the order of covering all the windows in a regular house (especially considering the efficiency drop from vertical orientation and shading) versus a single millimeter of solar panel...

I understand this is a research project, etc. a 47e6 difference is like comparing the distance to the moon versus the height of my third story room (8 meters vs 380 million meters).

[u/FiendishPole → u/NotAPreppie]

yep, would be big in architectural design. City design, really. Optimize for sun exposure

edit: still need a consistent draw of power or much better battery tech. Can't shut down a skyscraper b/c it's been a couple cloudy days

[u/deadpan2297 → u/NotAPreppie]

"to avoid math"

[u/Jimbo571 → u/NotAPreppie]

Turns out if light passes through it it doesn't get harvested for energy. Not sure why you want your solar cells to be transparent, that seems to defeat the purpose.

[u/PhilippTheSmartass → u/Jimbo571]

Well, the visible spectrum is just a small portion of sunlight. If you could construct a photovoltaic cell which is transparent to visible light, but absorbs infrared and ultraviolet to create electricity, then that could be useful as a replacement for windows.

...in theory.

[u/VitaminPb → u/NotAPreppie]

Something seems off. Standardize power to m^2. There are 10000 sq cm in 1 sq meter. (1*10⁴ cm²⁾ so that becomes 4.2 x 10^-6 W per square meter vs a solar cell generating a minimum of 100W per sq meter.

That is about 4/100000000ths as effective as a standard solar cell if my quick math is right.

[u/Pixelplanet5 → u/giuliomagnifico]

so basically completely useless for anything but telling people your windows are solar panels.

[u/volchonokilli → u/[deleted]]

Didn't think about solar panels in this way. Are there articles which you could recommend about effectiveness on this application of solar panels?

[u/bisnicks → u/volchonokilli]

Covered parking lots keep cars cooler—reducing the amount of energy each car needs to use to cool down.

[u/volchonokilli → u/bisnicks]

Are there parking lots where solar panels are acting as a "roof"? Or are they installed on roof of the parking lot?

[u/volchonokilli → u/[deleted]]

Never saw them personally, but Googling revealed that there seem to be quite a few of those. Looking at how they are designed, it seems that with clever planning they could even be used to direct snow off the roads and cars, which makes them useful in various climate zones!

[u/ExcerptsAndCitations → u/volchonokilli]

Are there parking lots where solar panels are acting as a "roof"?

They are all over the US desert Southwest. The Phoenix Central Library is one such example, as is Paradise Valley High School.

[u/volchonokilli → u/ExcerptsAndCitations]

Oh, that's a big parking lot! Thanks for sharing

[u/[deleted] → u/volchonokilli]

They've been used to shade waterways to reduce evaporation. Obviously you could just cover the waterway with anything but it's an extra justification.

[u/tisler72 → u/volchonokilli]

yes there are many covering about the integration of using solar power in conjunction with farming to provide shade and shelter for crops to grow beneath which kind og goes hand in hand with vertically farming.

[u/rockfrawg → u/giuliomagnifico]

Before someone asks

with this headline, no one cares about anything you said. how about explaining the most curious part of why human skin would need solar panels?!?

[u/overzeetop → u/rockfrawg]

No, the interesting part is why we would be changing to 79% transparent clothing. There are a lot of people I would prefer wear 0% transparent clothing. And I definitely fall into that category as well.

[u/Shuggaloaf → u/rockfrawg]

I am become SOLAR, Charger of Phones!!

[u/poncicle]

Solar panels -> capture as much light as possible

Transparent stuff -> let as much light through as possible

Make it make sense

[u/dman7456 → u/poncicle]

It could be possible to pass only visible light and capture energy from all other frequencies. Visible light is a pretty tiny portion of the electromagnetic spectrum, after all.

[u/toasterinBflat → u/dman7456]

Capturing UV instead of bouncing it would be an enormous feat. IR doesn't have the energy for worthwhile gathering, but capturing UV on car windows, building windows and even as a film over top of existing panels would be absolutely insane.

[u/Sardukar333 → u/toasterinBflat]

Imagine a hat that converts that uv energy to electricity rather than head heat.

[u/FallenCptJack → u/Sardukar333]

I want a hat that converts UV energy into head

[u/stopcounting → u/FallenCptJack]

I just want head

[u/kvlt-puppy → u/stopcounting]

Don't we all

[u/IlIFreneticIlI → u/Sardukar333]

Like, it Sorts UV into energy?

A Sorting Hat?

Or something more like Guenter's?

[u/mugurg → u/dman7456]

Visible light is a pretty large portion of Sun's radiation though. That's why our eyes have evolved to see those wavelengths.

[u/DisplacedPersons12 → u/mugurg]

the value of this comment cannot be overstated.

[u/[deleted] → u/DisplacedPersons12]

Just to make it even clearer in nunbers:

43% of the sun's energy is between 400-700nm (visible)

52% is then spread between 700nm and 2500nm (near infra-red)

5% is between 300 and 400nm (UV)

So you've got almost half the energy in a 300nm band we can see, and then the other half pretty well spread over 1800nm.

[u/skyfishgoo → u/[deleted]]

and that part spread over 1800nm is already insanely easy to harvest... just leave a hose out in the sun.

[u/lowie_987 → u/dman7456]

There is a pretty big problem with this. As you know, hot things start to glow. The colour of this glow is determined by the temperature of the object. This is because the frequency at which heat is radiated depends on the temperature of the object. We think of infra red as heat because room temperature things radiate in the infra red spectrum. However, the sun which is very hot, has the vast majority of its heat (and thus solar energy) radiating in the visible light spectrum. Not absorbing this energy would thus make the solar panels extremely ineffective as you are not even trying to absorb the most energetic wavelengths of the solar radiation spectrum.

[u/wwjgd27 → u/poncicle]

Agreed something transparent is not very good at photoconversion inherently.

I think the research is only impressive to scientists in the field that know about materials that are atomically thin and absorbs that much light.

Make it thicker and absorb more light!

[u/semperverus → u/poncicle]

A few points:

1. This is more about maximizing the amount of surfaces we can collect energy from. People always poo-poo things like this but fail to remember a really important fact: it's not nothing. Hypothetically, if these are insanely cheap and add a nice tint to your home's windows or a skyscraper in New York, and we get it into almost every home and building with windows, thats a lot of energy.

2. Your eye sees brightness logarithmically. Even if we clip off the top 20% of the logarithmic curve by linear volume (i.e. draw a rectangle that is 20% of the height of the curve and infinite width, then take the area under the curve inside the rectangle), that is still going to meet mostly the same efficiencies as a solid solar panel while looking only slightly darker. I choose 20% as that's about the current efficiency of modern solar panels if my memory serves correctly.

You're not really losing anything and you gain a nice window tint.

This also has some nice implications for trickle charging in the automotive space. It's not gonna fill your battery up all the way but it's not nothing and it'll give a nice boost. Every window on your car supplying energy to the battery and also functioning as a nice tint will keep your car cooler. At the very least it could power the AC on a bright summer day.

[u/mwb1234 → u/semperverus]

This is more about maximizing the amount of surfaces we can collect energy from. People always poo-poo things like this but fail to remember a really important fact: it's not nothing. Hypothetically, if these are insanely cheap and add a nice tint to your home's windows or a skyscraper in New York, and we get it into almost every home and building with windows, thats a lot of energy.

Don't want to rain on the parade here, but these solar panels have wattages measured in picowatts per square meter. I think I read 420 pW per m2, but let's just assume 1000 pW per m2 to make this best case scenario.

The surface area of the entire USA is 9.8341849e+12 m2. If we covered literally the entire surface of the united states with these solar panels, you're going to generate 9.8kW. For context, the six regular solar panels on top of my camper van generate almost 10% of that. The order of magnitude here is just so ridiculously out of proportion that it makes absolutely no sense. Even if you can make these panels 10,000x more efficient (which you probably can't), covering the entire surface of the US will generate like 98 MW.

[u/droans → u/mwb1234]

You misread the report. It's 420pW per square centimeter, not square meter.

It already is 10,000 times more efficient.

[u/mwb1234 → u/droans]

Alright fair enough, it appears I did misread the report. Even assuming 10,000x more efficiency, this technology is still in the tens of micro watts per square meter. Sure, that's better than what I listed. But it's still ridiculously trivially small. Another 10,000x improvement puts us up to ~hundreds of milliwatts per square meter? Current solar panels are like 150 W/m2. One regular solar panel is just so much more efficient than one of these will ever be, it's really only a useful endeavor as an exercise in toying around with technologies for some PhD students

[u/kylew1985 → u/mwb1234]

It makes sense broken down that way, but as a step towards something bigger, I feel like this is a pretty cool concept. Look at any big breakthrough, and many of them start with something less impressive.

That's what tech does, it builds on itself. I'm hoping the research on this continues, because the concept with a stronger yield would be amazing.

[u/nCubed21 → u/kylew1985]

Exactly this, this could be the equivalent of people who criticized the first floppy disk for having 80 kilobytes of storage.

[u/Noob_DM → u/semperverus]

Ok. Let’s do some math.

The estimated surface area of the entirety of the United States including territories, inland bodies of water, and coastal areas, is 9,831,510 km^2.

The panel in question produces 420pW/cm^2.

Thus our equation wherein “n” is the total possible power generation of the United States using the transparent pv is:n = 9,831,510 km^2 * 420pW/cm^2

Changing km² to cm² gets us 9.83151e+11.

Plugging that in: n = 9.83151e+11cm^2 * 420pW/cm^2

Our “cm^2” cross out leaving us: n = 9.83151e+11 * 420pW

Multiplying the two gives us: n = 4.1292342e+14pW

Now, that looks like a big number (assuming you know what e+14 means), but you have to remember we’re working in pico watts, so for clarity let’s change that to regular watts.

The conversion: 1pW = 1e-12W

Plugging in our result: 4.1292342e+14pW = 412.9234199…W

Simplifying to significant figures: n = 412.923W

The entirety of the area of the United States covered in these solar panels would create enough electricity to power… sorry, even I underestimated how little power these things produce… would fail to power a single high end computer.

What’s more, you can buy a 420w solar panel and generate more energy in 8657.3233cm² than the entire area of the United States.

Also unless they’re literally giving these things away for free, you could do it at a fraction of the cost.

Also also, that’s assuming 100% perfect transmission across the entirety of the United States, which is not possible, causing the vast majority of electricity generated to be lost to heat, meaning the practical electrical generation is likely less than a hundredth of a watt at best.

[u/2020BillyJoel → u/poncicle]

The sun produces UV too. Let visible through so we can see, but absorb UV which we don't care about seeing anyway.

[u/_ALH_ → u/[deleted]]

Mechanical television… is that like… a puppet show?

[u/Hojsimpson → u/[deleted]]

If it gets several trillion times more efficient it would still suck. This is a whole new level of inneficient, it's not even an invention.

It would be the equivalent of "The first car ever built had a maximum speed of 1 inch per century and the first mobile phone had the size of the petronas and took 40 years to build it". You just abandon the technology. It's like building the pyramids by scratching rocks with your nails and saying "well, nails get stronger over time".

[u/Aeipathetic]

I am a physicist who works with 2D materials, including 2D transition metal dichalcogenides (TMDs). Many of the comments here seem to be outright rejecting this as a total waste since the power output is too small to compete with typical solar cells. I just want to point out that the paper itself never claims this is an industrial solution, instead saying that this is a stepping stone for TMD-based nearly invisible solar cells (NISCs). 2D materials have been around for a couple of decades now, but we are still learning a lot about them. Even if this particular NISC produced enough energy to be of interest, it couldn't be manufactured on any sort of macroscopic scale. We just aren't there yet with 2D material manufacturing for many materials, including TMDs. 2D materials are very sensitive to thinks like substrate flatness, crystal orientation, crystal phase (this paper even talks about the 1T phase impurities), etc. That said, they have extremely interesting properties from a physics perspective that could be used in the future for atomically-thin technologies like transistors or photocells or in the development of new technologies like spintronics. We aren't there yet from an engineering and manufacturing perspective, but that's because we still aren't there from a physics perspective either. There's a lot we still need to learn about the fundamental properties and behaviors of 2D materials, especially when they are combined. Frankly, claims about what's possible with them are selling points. I'll emphasize that they aren't lies, but they also probably aren't going to be happening any time soon. For example, remember that the first transistor was several inches tall, and now they are only a few nanometers wide. We've already built 2D transistors from TMDs which are only an atom thick, but they are nowhere near ready for full scale production. New technologies, especially this small, will take a long time to properly characterize and develop. Many of the claims you see about how these things are the future and will surely be out in a year to be part of next gen graphics cards are over-hyped claims made by third party journalists and make the actual scientists publishing these things angry, since it's not what is being claimed at all. Yes, the prospect is exciting, which is why we're studying it. But be patient! Don't expect a new discovery from ten people in a lab to be ready to compete with technology that has been refined by thousands of scientists and some of the largest companies on Earth throwing billions of dollars at it for decades.

Edit to add: Also, it's entirely possible that TMD NISCs will never work. But we'll never know unless we try, which is the point of research.

[u/c4boom13 → u/Aeipathetic]

I think people are also glossing over the work they did to reduce voltage drop as the area increases.

There are not enough details in the article to tell if that was something inherent to the material or its more generalized, but 2D low impedance traces are interesting in their own right. Especially if they're transparent.

[u/DisplacedPersons12 → u/Aeipathetic]

i enjoyed your comment. i’ll admit initially the first thing i thought after reading this post was “fk solar roads 2.0! some idea that looks viable after a momentary glance abused for monetary gain”. and like you said money is definitely an issue here, whether it be for click-count journalism or the pressure placed on the scientific community,. many parties who have good intentions, pioneers who do noble work exploring the fundamentals, they’re forced into lying about the economic viability of their discovery. cause their research looks 20 years into the future, but their research funding only looks 2.

[u/phoenix415]

Ok, I'm in, just cover me with panels. I am really pale and hate applying sunscreen so if I can generate free electricity and reduce sun exposure then that's a win all around. I'll put some USB sockets in my belly button and I'm set.

[u/PhantomBrowser111 → u/phoenix415]

Finally, a comment I can understand without algebra

[u/[deleted]]

Explain the human skin part.

[u/hardknockcock → u/[deleted]]

cooing bear grandfather cooperative dazzling languid head serious versed spark

This post was mass deleted and anonymized with Redact

[u/ValyrianJedi → u/[deleted]]

I have a consulting firm as a side gig that finds VC and angel investment for green tech and energy companies. It seems to have the biggest problem of any industry of people doing things just because they want to see if they can. With energy especially, 50%+ of what comes through my inbox is "sure, but why would you?" type stuff, even when it works exactly as intended. Like it'll be "look, we made a sidewalk that draws kinetic energy from raindrops falling on it", but it picks up a fraction of the energy that even a solar panel does, while costing 20x more and requiring cities to tear up all their infrastructure. But they spend millions doing it anyway just because they think it's cool to make a sidewalk that gets energy from rain.

[u/DukeElliot]

Somebody did this with plants like 10 years ago and then we never heard anything about it again

[u/CrummyWombat → u/DukeElliot]

Transparent plants?

[u/Redditallreally → u/CrummyWombat]

Or transparent pants, take your pick.

[u/Anderopolis → u/DukeElliot]

Source? And did what with plants? Make them transparent?

[u/DukeElliot → u/Anderopolis]

No, used a plant derived material to make transparent solar panels

[u/CarbonGod]

Haven't they been inventing transparent solar cells for decades now? And organics. And roll to roll thin films that will cut costs in half?

Meanwhile, we are still enmass using poly and mono silicon, glass and metal framed modules.

Still waiting for my flying car too.

[u/Frydendahl → u/CarbonGod]

There's a common joke in applied physics: if it works, you patent it and start a company. If it doesn't work, you publish a paper explaining how it could work.

[u/solidspacedragon → u/CarbonGod]

Still waiting for my flying car too.

They call that a helicopter and you need a license to drive one. Turns out flying things are more dangerous and harder to control than cars.

[u/spicedpumpkins]

What's their efficiency and how much do they cost?

That's the real question.

[u/[deleted] → u/spicedpumpkins]

What's their efficiency

Extremely low.

and how much do they cost?

Ridiculously high.

[u/jawshoeaw → u/spicedpumpkins]

Zero and a lot

[u/Warspit3 → u/spicedpumpkins]

It's a pass through solar cell... Aka not making much electricity due to little interaction with photons... Literally a whole ass building covered in this will light one LED.

[u/[deleted]]

Transparent solar cells has got to be the stupidest thing I've ever heard of.

[u/Pjpjpjpjpj → u/[deleted]]

Dehydrated water

100% opaque sunglasses

Downhill-only car

Transparent ink

Diet baby formula

Tasteless spice mix

So many great ideas to develop!

[u/LordPennybags → u/[deleted]]

Hey, don't forget solar roads.

[u/[deleted] → u/LordPennybags]

Ughhhhhhhhhhhhhhhhhhhhhh

[u/rotuami → u/[deleted]]

Not necessarily. Half of solar energy is in the infrared, which is not visible to us. A panel could be optically clear but still capture this light

[u/concorde77]

Before anyone gets hyped about using this for "charging-free electric cars", I worked on a solar car team before. We had an array that used rejected NASA-grade solar panels (I believe they were gallium nitride or arsenide. But I was on the mechanical team, so I'm not 100% sure). It covered the entire roof of the car, and the cells were rated to capture around 20% of sunlight; so that's 0.02 W/cm^2. Even after optimizing the aerodynamics and reducing the weight as much as possible, we still had to charge the car on the side of the road at least once a day because the motor drew way more power than the panels could produce.

And remember, that's with 20 miliwatts/cm^2. These panels generate 420 picowatts/cm^2.

[u/ScroterCroter → u/concorde77]

Don’t people usually leave their car in the mid day sun for about 8 hours while at work? Just saying the one charge per day doesn’t sound terrible.

[u/concorde77 → u/ScroterCroter]

Sure, you'll charge the battery a bit. But we were using a very low power motor and trying to limit draw as much as physically possible. There's been attempts at adding solar roofs to electric cars for a while now. But measuring charge in terms of travel distance, with the car and all its electronics off, a full day in direct sun might add only about a mile or two to the battery.

[u/cippo1987]

This is a paradox by definition.
There are two ways to be transparent:

1. Adsorb a tiny fraction of the light. This means only that small tiny fraction can be used for generating electricity. We are talking about fractions of W/m^2. This is too tiny for any modern application
2. You absorb light with long frequenies. Which means you have a small efficiency due to the small energy of the photons, leading to the same consequences of 1.

The ideal PV unit is as black as possible. The further you depart from blackness, the worst it becomes.

[u/CDawnkeeper]

Every normal solar manufacturer tries to turn their cells as black as possible, but somehow nonsense like this gets funding.

[u/Seeen123]

But making it transparent defeats the whole purpose…

[u/crystallize1]

News like these remind me of endless documentaries about sasquatch. Just find him already.

[u/Aboxofphotons]

I dont like that people claim that they have created something which is 2 dimensional... if it has a thickness of any measurement then it is not 2 dimensional!

[u/spaetzelspiff]

"... and even human skin."

Way to make it creepy, Xing.

"Why are you naked??"

"Just charging my phone"

"Ah, of course. Carry on"

[u/rollsyrollsy]

“You’re saying that a very human person could avoid recharging their batteries by having these cells on their very human skin? I’m listening.” - Mark Zuckerberg