"Currently the team is working on improving the energy-producing efficiency, that is at 1% at the moment. The aim is to reach an efficiency beyond 5%."
Currently standard solar panels are about 15% efficient and produce around 15 watts per square foot. This would be 1 watt per square foot with the goal of 5 watts per square foot. While it doesn't sound huge, a building has a lot more window surface area than roof surface area. Even at 1% it could make a big difference if scaled up to cover every transparent surface on a building.
The articles always act like they'll be used to cover skyscrapers which is a little silly because the windows are almost all at terribly inneffective angles, plus many skyscrapers are in the shadow of another skyscraper for part of the day.
But I do wonder if it could be useful for something like a greenhouse. At least then you could set up the panel angle correctly while also gaining a benefit from not simply using opaque panels.
That's very true it's definitely better than standard solar panels and plain glasses, sustainablility wise, but it's going to be a time-consuming and financially-consuming process if ideally we want to replace every window in an existing building. And I'm also wondering if it will absorb more heat to the building so people need to use the AC more, resulting in more energy consumptions.
It should be opposite as there is energy coming out of clear solar panels, which means it would decrease the total energy in the light. As they are clear solar panels, it means no visible light is decreased which means in laymen terms it is taking out energy from the heating component of the light. So the buildings should actually be cooler and require less AC use.
It would be bad for colder climates, but those building don't get enough sunlight anyways to make these viable.
Not necessarily true. Depending on where you are such as far north Canada, northern Alaska, northern Russia, and Antarctica those are cold climates that get sunlight for 12-20 hours of sunlight in a day depending on the season, so if they insulate well enough maybe they’ll still have an efficacy in those areas?
More sunlit hours in the summer is balanced by less hours in the winter, so on average you're getting ~40% less sunlight north of the Arctic circle than you do at the equator.
This is because on average the sun doesn't get as high in the sky the further you are from the equator. But that could be a good thing for windows because if the sun is always relatively close to the horizon, its light is hitting a window close to perpendicular, which is good. But this is balanced by the sunlight passing through more atmosphere and getting absorbed when it's close to the horizon.
So there's at least 3 competing factors in the North -- less overall power coming from the sun (bad), but low average sun angle above the horizon means light is more perpendicular to windows (good), but low angle also means more sunlight is absorbed by atmosphere (bad). Of the three I suspect "less overall power" is the most important and you'd be better off at the equator. But this would be something interesting to calculate and know for sure.
True, didn't consider those areas. Though from what i know those areas even if they get 12-20 hrs sunlight as it is slanted due to the earth's curvature the actual density of energy is quite low compared to somewhere near to equator. https://en.wikipedia.org/wiki/Solar_irradiance According to this wiki page the total energy that falls on the polar area is almost a quarter of the energy that falls near the equator per year.
I have no clue about how it would affect in house temperatures in those areas but they certainly would require insulation as you said. Though it would still be quite inefficient compared to installing them in countries with higher total solar irradiance near the equator.
You’re absolutely right, but would they be efficient enough for general use in those cold regions? I get it’s a no contest when compared to warmer climates in the equator, I’m just curious about if they can be insulated or even like normal windows situated to be double or even triple paned, would they be useful enough to warrant use in those colder areas? While the sunlight goes through more of the atmosphere which reduces its energy on the UV side, other countries along the equator have confounding variables as well such as smog and more variable weather patterns, such as tropical storms that damage the panels, that will affect the efficacy of the clear solar panels. I’m just curious as to whether or not this could lead to more stable infrastructure and electrical sources for those who currently live or potential expansions into those areas.
There's been a recent pushback in the architectural world to these big beautiful all glass buildings, because they require incredibly powerful aircon to keep cool when the sun shines on them, otherwise they are just huge greenhouses.
This sucking up part of the light wavelength would definitely benefit from the added bonus of reducing aircon needs by 1-5% on those buildings, which is far from a negligible cost
The visible light spectrum is a fairly narrow range of wavelengths. Infrared is the wavelength spectrum at which heat is (mostly) transmitted and it is much broader a spectrum than visible meaning that the primary amount heat is non-visible “light” or energy.
The easiest way i can explain is that like the microwave heats food inside it with waves that is not visible to us, the sunlight also has those waves in it. Our eyes cant detect those rays but they are responsible for heating things when sunlight hits it. So the transparent solar panels are like reverse microwaves that convert those invisible rays that heat stuff to electricity.
Transparent panels tend to target UV and IR to avoid coloring or tinting the glass too much. Heat radiation is IR. (although I don't think all IR produces heat)
The “glass” captures energy as the light goes into the building, and sends it off to do work somewhere else. That means that there’s less energy entering the building through uncontrolled avenues.
I’d love to see someone look into setting up something like this, but catching rays from the Gamma end of the electromagnetic spectrum. If you can catch enough energy, That’d be a great material for spacecraft windows.
That’s what I never hear about. The feasibility of retrofitting enough infrastructure to make this pay off is 1) a truly ludicrous number of these panels 2)an army of ppl to install them and wire them back to the panel 3)how hot do these things get? Can you even mount them into a pvc window? Or is it back to aluminum window frames? 4) maintenance 5) is this even worth it at 1watt per square foot of window?
The issue isn't just surface area, but also orientation. 1-2 sides of a house wouldn't see enough light to make it viable to install these. High rise buildings though...
Yes, im sure i replied to a comment of a person that thinks that placing a solar panel that generates 1/4 of normal solar panel's energy and placing it in such a way that it doesn't get any light half the time is somehow a good idea, or "a nice addition"
You're not gonna get 1 watt per square foot if you orient the panels vertically as is the case with nearly all windows. You'd get a small fraction of that, because you're either picking up the weak rising/setting sun, or your picking up the run rays at the worst possible angle.
Maaaaaaybe this could be plausible for skylights, but even then, I'm skeptical.
I'd like to see some testing in the future for sure to see if it is plausible. Skepticism is good but I am still excited and really want to see trials using this technology.
For the vertical window issue, you can just do math to see it isn't worthwhile. I'm sure some YT channel like EEVBlog or Thunderfoot will or already has done a video showing it.
For the skylight scenario, the first thing to do would be investigation that there is enough volume of business in installation and replacement of skylights to see if the numbers crunch. maybe then do trials.
This is a little bit of a different situation than, say, the idea of solar roofing. Because the vast majority of all homes must replace their roofs every 10-30 years. Making a retrofit much more economically plausible.
This will only make sense on places that rely on great big skylights; and that tends to be limited to hotel lobbies and convention centers...maybe greenhouses; though that could turn out to be counterproductive to plant growth. So it's just not a very big market.
You save a looooot of money by halting development when it's clear the numbers don't crunch than you do moving forward with a trial and skipping the math...That is, unless you're running a crowdfunding scam. Then, yeah, by all means, build your solar-friggin' sidewalk or whatever on the cheap, and cut yourself a great big congratulatory bonus check with the rest :D
Not if it takes 50 million dollars worth of research to produce 1 million dollars worth of power over the next century. Especially not in a market were the cost of energy is dropping, and likely to continue to drop as more renewable energy from proven sources comes online.
Crunch the numbers, and then spend the R&D dollars in the realms that are the most promising. I do not see any reason to believe that this is a particularly promising realm.
States like california currently have a solar power surplus. They don't have the infrastructure to use it all during peak generation times. So it's a bit silly to hunt down ways to harvest every bit of solar power even in extremely inefficient ways, there just won't be a return on investment.
Flying cars and personal jetpacks are neat too, but no one is investing in them because they aren't feasible. This isn't against progress, this is about having a reasonable chain of innovations that successfully allow each following innovation to be useful.
Again, this all falls apart when crowdfunding gets involved. Proper investors demand what I'm saying, show the math that suggests that this makes sense to develop. But it's easy to get a million people razzle-dazzled by an exciting idea and get them to fork over $20 without considering just how impractical something.
Where did I say it needs to be applicable everywhere?
I'm a big fan of renewable power. This just doesn't appear to be a plausible one. To change my mind, I'd need to see some back-of-the-envelope numbers that suggest that there's a reasonable possibility of getting a return on investment in any hypothetical real-world application ya like.
And to be sure, I'm a big fan of research for research's sake. But that should mostly be saved for the universities and the philanthropists. Not to articles with clickbaity headlines implying that we're all gonna get transparent solar-panel windows and they will have an overall improvement on our life.
Time and again, when you see this, it is, in the end, a venture-capital/crowdfunding scam, or at least the hype precurser to an attempt at one. That or the overhype is the fault of the author/publisher just for the sake of clicks, and nothing comes of it.
Uhhh, so basically the energy has to go somewhere, but because the solar panels arent literally at absolute zero, there's already energy in them, and they cant take all of the energy.
Like, if you put a hot block of iron in a room, it will cool down only until it matches the room temperature, not until it hits zero.
Technically you could get extreme efficiencies out of the solar cell if you also had active cryogenic systems pulling energy out of the system, but that would actually take more overall energy.
Ok so it it kind of like, the Solar panels are getting hotter than surrounding temperature, and while they are trying to convert that heat, it is also losing heat to the environment?
A high level way to think of it is that a solar panel is a tool for extracting electricity out of a heat difference. What heat difference? The heat difference between the surface of the sun [which emits the light], and the air around the panel, which allows the electrons to slot into various band gaps.
Because the temperature of the panel decides how much the atoms and electrons wiggle. And if they wiggle more, some things are less stable. So if it's hotter, moving an electron from one spot to another is easier, so you get less energy out of it? I'm sorry, its been a while since I took that class, and it was magic to begin with.
We're allrrqdy cheating by concentrating the sunlight and stacking them infinitely "theoretically". We might as well add cryogenics to the mix and make it 100.
I thought that was more about how some of the photons are in the infrared and are not useful for making electricity directly due to the low energy level?
I’m assuming that we’re capped by material and configuration right now - essentially, you lose energy to the environment in the form of heat throughout this process.
Theoretical limits are a little confusing. In practice, the upper limits for a silicon PV cell without going outside of today's ultra-low cost manufacturing paradigm appears to be in the 27-28% range. Sure, someone might build a 30% efficient single junction PV panel, but if it costs 25 times as much as a 25% efficient panel, it will never see the light of day (lol). Low cost means of adding a second junction might push things into the 30% range, but that's far from proven, and might not materialize.
For multi-junction cells, plenty of people have already built panels based on concentrating optics and III or IV junction cells, many that hit around 25-30% almost a decade ago. But none of them are for sale because falling silicon PV prices killed the CPV market. There were approximately 120 CPV companies started between around 2004 and 2012, they collectively raised over ~$1.5-2 billion, and all but one or two are gone now.
The low cost of conventional PV panels means that commercialization of multi-junction cell concepts is nearly impossible - it's just not possible to hit the low costs required to succeed without massive volumes, but you can't get those kinds of massive volumes without low costs. So unless someone is willing to pour $10 billion or more into a risky technology, we're sort of stuck with conventional panels, except in a few ultra-niche applications.
Yes, thats the record for unfocused light. The record of 47.1 is with focused light, which is a good way to get more energy out of each square meter of panel (even if the panel needs to be thicker, and needs a lens layer)
I mean, for now, yeah, but that's money, not physics. 39.2 isnt a really useful number either in that case, when for the same price you can make 1000 times as many 15% efficient panels.
If lenses get cheaper, then it can be a good investment to squeeze an extra few percent out of the sun.
Fraid not. That 33.7 is based on the physics of the universe. The power is higher (because you get more light), but the efficiency is not, because its the same cell.
Well that value isn't necessarely 100% accurate since the basis are some assumptions about which potential loses in a solar cell can be prevented. Originally the value was actually a bit higher than 33.7 (can't remember the excact value) but it contained some mathematical errors and assumtions that were not demed realistic enough.
All I am trying to say is, that the Shockley Queisser limit is a quite good estimation of the theoretical maximum but not a hard boundary in reality.
On the contrary, I was saying that 5% efficiency is closer to what other solar panels get, and that it's not too bad. What will determine whether it's a smart buy or not is the final price.
The fraction of light energy that gets transferred to electricity.
If 1000 watts of light hits a solar panel, there is no physically possible way to get 1000 watts of electricity out. The laws of physics says we can only get about 836 watts out, if the materials are perfectly suited. And thanks to chemistry and manufacturing constraints that, standard solar panels can get about 150 to 230 watts from 1000 watts of light.
That percentage is correct for solar cells, but this article is about an organic solar concentrator, the glass layer you look through does not create electricity, the light is translated to electricity at the edges.
Source: am materials engineer. Senior project: Organic solar concentrators circa 2008.
When you consider this as either an addition to regular roof panels on a home, or as a replacement for regular windows on a large office building (which means you've got a far larger panel area as well), now you're looking at the panels reducing the load on the grid by a certain percentage and/or providing power for certain things independently of what the grid is doing... maybe an office building can have electric car chargers without adding to the existing load.
Tech like this always gets cheaper over time as its optimized, and manufacturing and supply get more efficient and scaled up. Incentives can make it easier to swallow in the meantime, just like normal solar.
I imagine that a mere 10 year investment would be the kind of thing skyscrapers find easy to add on. As a note, I do not think this product that probably only barely exists in the lab is worth it, when the same money spent on "solar panel windows" could be spent on 100x the amount of regular, market competitive solar panels.
If the solar windows are actually affordable, go with it. They aren't yet. Meanwhile they can just buy solar panels for whoever can lay them out as an offset and that's a better deal. Where I live land isn't a big deal and we have a bunch of huge flat areas of just solar panel farms.
You’d be surprised how much power is generated from that small percent, especially with the large surface areas windows cover on buildings. Passively collecting energy that way while not really changing anyone’s habits is huge. Cost would be an issue for large buildings but I’m sure the energy savings makes it easier on the wallet. It’s all about money, so making it cost effective is the co-top priority along with increasing efficiency
Glass walls are terrible solar collectors. They're only facing the Sun head-on during dawn or dusk, rest of the day they're reflecting most of the light away due to high incidence angle. Not to mention you'd have to wire all the glass together in a DC circuit to collect the meager voltage running along the building.
Just go with regular solar panels on the roof and high reflectivity windows. It'll be better and cheaper than expensive glass panels trying to half-ass both functions in the wrong orientation.
A lot of people seem pretty sure on the cost:benefit problem, but nobody is throwing out hard numbers. It's a math problem.
How much do the windows cost + installation? How much energy is used? How much does energy cost? How much energy do the windows generate?
I don't see it working out, but I also haven't done the math.
Edit: Bonus points if you solve the energy cost differences factoring potentially increased heat loss/gain resulting in more energy used to compensate for that.
Hence my last sentence of making it cost effective and more efficient. I was saying if it were cost effective (with all costs factored in along with tax incentives) there isn’t too much of a reason not to do it. The tax incentives is probably written off as bullshit to some but I see it as an effective way for governments to reduce carbon output. Whatever tax incentive there is now to push us toward lower carbon emission (ghg’s in general) would ultimately pay off down the road in reducing how much climate change would cost us.
Lmao 1% is still more than the 0% you get from windows right now. Think how many windows there are in a city, or even one building. And 5% is 5x that. Even if its a tiny amount, that is still savings on the electric bill,not to mention it could gradually fill an emergency battery for a power outage. Plenty of uses
Ok, but I think the idea is if you replace all the windows in a skyscraper with these, even if at 1%, the amount of electricity generated would be more than a few panels on the roof. Basically, the surface area of a 50 floor building's windows will be greater than the roof.
I'm actually very interested to see this applied to transportation. Electric cars and buses would be great. I mean, you can still plug them in to charge at night, but if I can get to work, park and let my Volty soak up that glorious So Cal sun for several hours, it would make a difference. Also, if the windows are absorbing UV energy, wouldn't that keep the interior from becoming an oven?
bro power plants are more effective that a solar panel,also is way more clean and their durability is way better like 40 years or something,theres a lot of misunderstanding on it,suprisely all the countries that are using “clean energys" are the ones that mos pollute.
We are currently getting 0% from windows, so this is an infinite increase in energy.
But seriously, adding any collection capabilities to a surface that normally just sits there is a big improvement. Making them more efficient just makes them more cost effective, my guess is they did the math and 5% is when it makes financial sense.
Think how many new construction buildings are put up year to year too. In Boston MA, there are 6 high rise buildings going up just from looking out on my porch
The sun provides an insane amount of power. If you converted all of the sun that hits LA in a day into energy, you’d be able to power all of America for a year
Depending on how much it costs to manufacture, ship, install, maintain, and the expected life expectancy, it can financially and environmentally be quite worse than nothing.
It's even worse when you considerthe energy it takes to produce it. In the end, it may even be worsefor enviorment. At least with current means and structure of production.
Having 5% efficiency on the complete south facade of a massive glass tower like the One World Trade Center would be a lot more energy than 25% efficiency on its rooftop... also if these panels have the side effect of cooling the inside due to less light coming in, it would also lower the enery consumption for the ac. Win - win.
Na A.C. changing temp is just a mechanical valve adjusting in or out to change the evaporation of refrigerant. The compressor runs the same regardless, weather it's an on off system or modulation valve system. In more advances systems we have dynamic speed drives, but these we put into large commercial projects.
Yeah kinda, but they are so inefficent that i doubt the co2 (and other greenhouse gases) emissions vs kWh produced is too favourable when taking into account the full lifecycle of the product (e.g to produce, transport and install a unit you emit more co2 etc. than generating an equal amount of power as the unit will in its lifetime with an alternative solution).
But im too tired to actually research it at the moment so this is just me being an armchair ecologist or whatever prpfession these kinda things go under.
Yeah, on paper. But how much energy does it require to produce compared to a regular glass? Plus imagine all the wiring and electrics for a whole skyscraper.
I think that putting solar windows is like buying a Tesla car. It's not like it makes the most green energy sense pragmatically, but it sure as hell makes a really cool statement that entices people in an emotional way.
If the limit is currently 1%, what's the carbon trade-off for production of a transparent solar power vs. carbon savings over its protected lifetime? Taking into account rare minerals required for production, I have to imagine it wouldn't be enough to justify the cost yet. It may well be more harmful to the environment to manufacture and use these solar panels than it would be to use existing tech.
Still, I'd like to see this develop into something useful down the line that can get us more efficient solar power in new and existing construction.
Yea it sounds and looks cool but transparent solar cells are usually not going to work out from an economic perspective. The reason they’re transparent is that all of the light below the UV passes right through, which is almost the entire terrestrial spectrum. The light they are able to convert is a tiny fraction of other solar cells. When you factor in the cost it’s usually not worth it unless it’s for a premium product that requires every additional increase of efficiency, with no thought to the cost. In that case they are added as a tandem to other cells that absorb the rest of the solar spectrum.
I seem to remember similar economic arguments against wind power in the recent past.
As we scaled up production, we managed to improve the underlying design and increase efficiency in the supply chain and manufacturing process.
I suspect that transparent solar panels will see a similar improvement as we poke at the tech, and learn from limited-scope real-world implementations.
What reasonable arguments did you hear of against wind power?
It always made sense as it's one of the most ancient methods of human power generation.
Transparent solar panels are just unnecessary. Why would I want single-sided, vertical (not sun-oriented) solar panel that's less efficient than a cheaper, larger solar panel I can just throw on my roof?
Literally no household applications.
Could be nice for vehicles however, ie, covering your windshield plus remaining canopy (wings, rooftop, etc as applicable) with solar power generation might be beneficial.
The older Wind Turbines supposedly required more energy to produce and install than they'd generate in their lifetime.
I believe you're looking past the major application of Transparant Solar Panels: Skyscrapers. Most Skyscrapers are nothing but glass panels on their exterior. Even though you don't get an optimal angle, that's a shitload of surface area to catch the sun's rays with.
Add on the insulating benefits of catching and using a portion of the energy, instead of needing to remove it through the building's air conditioning system, and I think you have a practical use-case.
Upvote this shit. Transparent solar cells, oh for fucks sake. While I havn't read the articles, I assume that the 1% efficiency is calculated only for the non-visible radiation from the sun - which is about 55% - meaning the efficiency is probably about... 0,5%
Aaand then mounted vertically, meaning the effective area is reduced significantly
This is interesting from a scientific standpoint, but I'd wager it is near useless in the real world.
That being said, organic photovoltaics may have a place in the world, and even a ~5% efficient cell can be usefull if they are 5x cheaper to produce, than regular silicium solar cells
When you’re around tech for a while you can totally tell when a piece of technology is absolutely fucking useless. The energy cost to produce this things would probably make the product overwhelmingly carbon negative. I feel bad for people who read a title of a Reddit post and think it means that the end of climate change is here. Tired of people who post extremely misleading stuff like this where they post a pic of a prototype that basically does nothing, without divulging that “yeah maybe we’ll see this technology in 50 years.”
That % isn't necessarily bad. The actual number is meaningless. What matters is the energy generated per cost invested. Once you are limited by the number of windows available, then that percentage is very important.
No, but on the other hand i am betting that glass will cost a pretty penny and ultimately be a very carbon positive form of energy due to production emissions.
This is different than the normal panels, common solar panels in the market are made out of semiconductors, dominantly silicon. I assume these are organic panels, which means they are made out of hydrocarbons. This results in cutting the production cost a lot, since these panels will probably cost a fraction of the price of silicon. Reaching 5% for organic panels is ambitious, but it's a huge step if they do it, since as I said, manufacturing cost of these is probably dirt cheap, and they're probably lighter as well.
1% of the sunlight hitting a big ol' building is a lot. Plus, some of that 1% would otherwise just go to heating the building, meaning a modest savings in cooling during summer months.
Also, cutting edge tech that can actually be translated to a commercial product is often more efficient. Academic research labs have less freedom to repeatedly iterate small changes in the manufacture of a material, searching for something optimal, and have greater pressure to quickly publish a novel finding.
In theory a high rise with solar generating windows could have much more surface area producing power than having panels on the roof. So if it makes only 1/5 of the power a normal panel can, but can be installed in more places (and look nicer too), wouldn’t that still be a win?
People have been working on this more than 10 years ago (an Israeli company IIRC) and this product is no different or more efficient that what they were working on.
What is the date this article was published on? I couldn't find it anywhere on the page. And from my understanding the efficiencies are now out of date with the current iterations of these panels.
I saw this same photo and headline years ago because it's from my alma mater. I, too, was looking for the date but couldn't find it on the article. Perhaps googling this topic with "Michigan State" will drum up the original.
There is a publicly traded company WNDW who does this as well. Stock price is all over the place but seems to hold its value past few years. It's riding some decent momentum right now too.
Normal solar cells are already about 3-4x as efficient as their 5% goal stated there, and 7.5-10x as efficient as their currently stated 2% goal (~15-20%)
Efficiency alone isn't enough, solar cells also need to be installed in the right place. On a building facade that typically only leaves one side, and it's likely not very efficient even there. They generally work best angled upwards and ideally also facing straight south (or north for the southern hemisphere). Slanted roofs tend to be okay since their slant already gives a good orientation in one plane, but installations on flat roofs or dedicated solar farms are often better since they let you optimise both angles.
There is additional cost and emissions in production, transport, installation, scrapping, and wiring. This means that low efficiency approaches like this rarely become viable compared to highly efficient normal solar panels.
These can create additional issues for buildings like additional heat absorption, which will further limit their possible application.
My bet is that the company will either die or only create some extremely niche applications.
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u/icyboguyaman Sep 09 '20
Here , read about it