Low-cost 'transparent' solar cells reach new efficiency record, electricity-generating...

Alfonso Maruccia

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Forward-looking: Dye-sensitized solar cells (DSCs) are cheap, transparent, and flexible. The promising technology set a new record in efficiency for turning visible light into electric energy, making it viable for use as energy-collecting windows.

A team of scientists at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland developed a new kind of dye-sensitized solar cell (DSC). Its vastly improved efficiency promises cheap, transparent, and ubiquitous energy-generating panels. Widespread adoption could help the world build a future free from fossil fuels and greenhouse gases.

Also known as Grätzel cells, modern DSCs were co-invented by Brian O'Regan and Michael Grätzel in 1988 as an alternative low-cost solar cell. Based on a semiconductor formed between a photo-sensitized anode and an electrolyte, the photoelectrochemical system turns electromagnetic radiation into electric energy. The panels are transparent and cheap to manufacture. They can be fabricated in multiple colors and are already used in some buildings with glass facades, like the Swiss Tech Convention Center.

Furthermore, it is possible to manufacture DSCs to be flexible, meaning they could be suitable to embed into portable electronic devices and IoT appliances. Current dye-sensitized solar cells are sold commercially on a large scale but are less efficient than conventional solar panels in converting sunlight to energy.

Recent advancements in photosensitizers and other components of DSCs have improved the conversion efficiency under both solar and ambient light conditions. Now, the EPFL team has developed a new approach that can bring the efficiency rate up to 15.2 percent for the first time under simulated sunlight, maintaining long-term operational stability for over 500 hours during testing. By increasing the active area to 2.8 cm2, the power conversion efficiency reached a maximum rate of 30.2 percent.

In their study published in Nature, the scientists achieved groundbreaking results by improving the packing of two newly designed photosensitizer dye molecules to enhance the DSC's photovoltaic performance. The team explains that the new photosensitizers can harvest light across the entire visible light domain.

These new findings "pave the way for facile access to high-performance DSCs and offer promising prospects" for different applications. Efficient DSCs could one day become power supply units and battery replacements for low-power electronic devices, using simple ambient light as the primary energy source. At the same time, large buildings and greenhouses could feed the power grid by generating more power than they use.

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30% has long been thought of as the sweet spot for solar, where efficiency comes within a stone's throw of fossil fuel sources in the first world...but only where solar is truly viable to begin with. Even in coastal FL solar isn't super productive thanks to the ever-changing weather. Large generating facilities in the desert southwest still make more sense than mandating cells on every rooftop, greatly increasing home costs for a marginal return. The "green energy" lobby has also done all it can to downplay the serious environmental consequences of solar as well - the production is very toxic, often relies on conflict minerals and the recycling is not only dirty but operates at a loss. Same goes for battery technology. As someone who despises being forced to live in a city after most of a lifetime spent in the country, I long for the day that loud mufflers, loud engines and "coal rolling" will be things of the past. But to make that happen the technology has to be ready, and no matter how we fudge the numbers we're simply not there yet. Solar windows will be a dream come true if they can pull it off. Here's hoping that Big Energy, who stands to gain the most from the switch the renewables, keeps investing billions in better solutions. When the age of green power finally arrives (which I'm sure I won't live to see) let's just hope they don't try to sell us sunlight at the same price as oil.
 
Even in coastal FL solar isn't super productive thanks to the ever-changing weather. Large generating facilities in the desert southwest still make more sense than mandating cells on every rooftop, greatly increasing home costs for a marginal return.

I'm in the UK where it now Autumn so crap British weather and all that. The 12 panels on my roof have produced 250.6kWh in October so far and in the same period we have used 278.8kWh so for 28 days of electricity I have been charged £5.35. When the days are longer we are pumping so much excess energy back in to the national grid the money we get back via an export tariff helps to pay for the months with shorter daylight.

In the UK a £6000 4.4kW system has a payback time of around 4.2 Years at the minute due to high energy prices, personally I don't care about the payback time and am just happy to stick it to the energy companies and not be contributing so much towards their massive profits.
 
So far every advancment has been a big plus for the solar industry. The only negative has been local power companies that attempt to block or charge for people going "off grid" and the politicians that support that policy. This is one area where a Federal policy/law needs creation that gives each person the right to go off-grid without penalty AND force energy companies to buy back power at some fixed rate, like 75% of current KWH price.
 
To be 100% honest, nothing beats Nuclear Power stations

Small Islands around the world could be setup and work

Hmm, let's see:
1 - Any idea about the cost of building something so remote, immense, expensive, complicated, with a huge environmental impact, PLUS the cost of running and maintaining and housing for the employees? You need lots of people run, maintain and control those behemoths!

2- What about schooling, food and infrastructure for those employees on those "small, remote islands"?

3 - Any idea about transporting generated power across the globe to the countries that need it?? Too bad we can't beam it! billions of tons of cabling will be required......

4- Where do you plan to keep nuclear waste (nuclear rods that have expired but still-radio active for the next thousands of years)? Next to those people who work there?? Nuclear waste is always an after thought....best to be ignored.

Otherwise, sounds like a great plan!!
 
Hmm, let's see:
1 - Any idea about the cost of building something so remote, immense, expensive, complicated, with a huge environmental impact, PLUS the cost of running and maintaining and housing for the employees? You need lots of people run, maintain and control those behemoths!
I agree with that. I personally think that the best and most overlooked sources of electricity are geo-thermal and hydroelectric. I do not understand why these are ignored.
2- What about schooling, food and infrastructure for those employees on those "small, remote islands"?
Yup. Nuclear plants can't effectively run themselves like hydro and geo-thermal plants can.
3 - Any idea about transporting generated power across the globe to the countries that need it?? Too bad we can't beam it! billions of tons of cabling will be required......
Yup, and depending on how remote it is, even with enough cabling, it may still be too far to be all that efficient.
4- Where do you plan to keep nuclear waste (nuclear rods that have expired but still-radio active for the next thousands of years)? Next to those people who work there?? Nuclear waste is always an after thought....best to be ignored.

Otherwise, sounds like a great plan!!
Well, this is where the danger of nuclear waste is a bit exaggerated. I used to think as you do because I didn't know how it was taken care of. I came across this video by Kyle Hill (The guy from "Because, Science") and, knowing his previous work, it assuaged my own concerns about it. Now I actually think that nuclear energy is a good option. Of course, I don't think that it's as good as geo-thermal or hydro, but far better than burning stuff:
 
Well, this is where the danger of nuclear waste is a bit exaggerated. I used to think as you do because I didn't know how it was taken care of. I came across this video by Kyle Hill (The guy from "Because, Science") and, knowing his previous work, it assuaged my own concerns about it. Now I actually think that nuclear energy is a good option. Of course, I don't think that it's as good as geo-thermal or hydro, but far better than burning stuff:
My God. Avro, Brother. You've seen the light :) ;) :)(y) (Y)
 
I agree with that. I personally think that the best and most overlooked sources of electricity are geo-thermal and hydroelectric. I do not understand why these are ignored.

Yup. Nuclear plants can't effectively run themselves like hydro and geo-thermal plants can.

Yup, and depending on how remote it is, even with enough cabling, it may still be too far to be all that efficient.

Well, this is where the danger of nuclear waste is a bit exaggerated. I used to think as you do because I didn't know how it was taken care of. I came across this video by Kyle Hill (The guy from "Because, Science") and, knowing his previous work, it assuaged my own concerns about it. Now I actually think that nuclear energy is a good option. Of course, I don't think that it's as good as geo-thermal or hydro, but far better than burning stuff:

I totally agree, nuclear energy is an option.

Assuming people are realistic about them and are not blind or dismissive about other options.
 
My God. Avro, Brother. You've seen the light :) ;) :)(y) (Y)
I saw the light long ago, but I still don't think that nuclear is the best choice. This is because no matter where you are in the world, geo-thermal is available and while sure, drilling a hole that deep might be an expensive preposition (depending on where in the world you're doing it), it pales in comparison to the cost of a nuclear reactor and its fuel.

The other thing is that, while I understand that the possibility of a meltdown is extremely remote, a geo-thermal plant has literally no capability of that ever happening. If a geo-thermal plant has a catastrophic failure, the result is just a bunch of steam in the atmosphere instead of widespread radioactive contamination. A geo-thermal plant therefore doesn't need to be situated in a remote location. Iceland pretty much runs entirely on geo-thermal. Sure, the heat is closer to the surface there but that just changes the required hole depth.

I prefer hydro to nuclear because it's perpetual, renewable energy that's dirt cheap to produce once you have the plant up and running. The cost of the plant, again, pales in comparison to the cost of a nuclear plant.
 
I prefer hydro to nuclear because it's perpetual, renewable energy that's dirt cheap to produce once you have the plant up and running. The cost of the plant, again, pales in comparison to the cost of a nuclear plant.

That the thing with being green these days: you can pick and choose priorities and dismiss the others.
1. Hydro is not perpetual, droughts are a thing. You might run out of water at some point
2. You HAVE to disturb, mostly destroy an ecosystem: the river. It's cheap energy, though. Back when biodiversity was a priority I'm pretty sure it was a green stance to be against hydro. Times change...
Same idea with wind: it kills birds, apparently, but it's "green energy" (not cheap, though)
 
I saw the light long ago, but I still don't think that nuclear is the best choice. This is because no matter where you are in the world, geo-thermal is available and while sure, drilling a hole that deep might be an expensive preposition (depending on where in the world you're doing it), it pales in comparison to the cost of a nuclear reactor and its fuel.

The other thing is that, while I understand that the possibility of a meltdown is extremely remote, a geo-thermal plant has literally no capability of that ever happening. If a geo-thermal plant has a catastrophic failure, the result is just a bunch of steam in the atmosphere instead of widespread radioactive contamination. A geo-thermal plant therefore doesn't need to be situated in a remote location. Iceland pretty much runs entirely on geo-thermal. Sure, the heat is closer to the surface there but that just changes the required hole depth.

I prefer hydro to nuclear because it's perpetual, renewable energy that's dirt cheap to produce once you have the plant up and running. The cost of the plant, again, pales in comparison to the cost of a nuclear plant.
The ocean with it's never ending currents. If we could capitalize on that without the investment costing more than the benefit. that would be awesome.
 
The ocean with it's never ending currents. If we could capitalize on that without the investment costing more than the benefit. that would be awesome.
There's a lot of research going into the idea of tidal power in the Canadian province of New Brunswick as well. The Bay of Fundy has the highest tides in the world and they've managed to get some power out of it. Honestly though, all we need is a dedication to geo-thermal electricity and everything else is rendered moot. We spend so much time and money researching other sources of power when geo-thermal is literally all that we need.

Here's an article from MIT about geo-thermal power generation:
Tapping into the million-year energy source below our feet
 
So far every advancment has been a big plus for the solar industry. The only negative has been local power companies that attempt to block or charge for people going "off grid" and the politicians that support that policy. This is one area where a Federal policy/law needs creation that gives each person the right to go off-grid without penalty AND force energy companies to buy back power at some fixed rate, like 75% of current KWH price.
While I am all for it, the only problem with a Federal Policy on energy is that only one party supports it, and if it were passed by that one party, the other party would rescind it if/when they were elected. It's been that way since the energy crises days of the 1970's and the Carter Administration. The Carter Administration implemented green energy policies and policies that prioritized energy research, and Ronnie Raygun promptly dropped and ditched all of them.

As I see it, it amounts to a giant dirt pile that is moved from one side of the White House lawn to the other when the presidency moves from one party to the other. And I also see it as a waste of taxpayer money as well as a detriment to any true advancement since one party has decidedly supported anti-science policies. By the time the US gets green energy figured out, the White House will be under water.
 
That the thing with being green these days: you can pick and choose priorities and dismiss the others.
1. Hydro is not perpetual, droughts are a thing. You might run out of water at some point
That really depends on where you are. In Canada, droughts will NEVER be a thing because we have more lakes than the rest of the world put together. In a lot of places though, you're right.
2. You HAVE to disturb, mostly destroy an ecosystem: the river. It's cheap energy, though. Back when biodiversity was a priority I'm pretty sure it was a green stance to be against hydro. Times change...
Same idea with wind: it kills birds, apparently, but it's "green energy" (not cheap, though)
Yes, that is true but disturbing a local ecosystem to save the entire planet seems like a bargain to me. This is why I think that the ultimate solution is geo-thermal.
 
Well, this is where the danger of nuclear waste is a bit exaggerated. I used to think as you do because I didn't know how it was taken care of. I came across this video by Kyle Hill (The guy from "Because, Science") and, knowing his previous work, it assuaged my own concerns about it. Now I actually think that nuclear energy is a good option. Of course, I don't think that it's as good as geo-thermal or hydro, but far better than burning stuff:

A friend of mine works in research in nuclear waste and in fact there's are so many types of pollution that it becomes hard to evaluate and even harder to approve. There is the nuclear waste that everybody knows which is what is extremely radioactive, but in the long term there is also all the materials near the reactor which is very radiocative. Also even the water (if I remember well its iodine content especially) that is used to cool it down is radioactive, and this is a tremendous amount of matter. Excuse the lack of details, it's been a while since I heard her speak about it.
 
Even if efficiency of electrical generation goes to 100%, reliance on fossil fuels will remain until we solve the problem of providing power when the sun in unavailable (night, cloudy days, etc.). I live in California which has a very progressive agenda on solar energy. However, during the summer we are all encouraged to reduce energy consumption between 4-9pm---which is when the production of solar energy drops, but is ironically when most people are coming home from work and need energy the most to cool their homes, make dinner and, well, live. And of course, this is when fossil fuels are relied upon. I wholeheartedly support renewable energy, but the focus seems only on one part of the equation. Current battery storage technology remains expensive, requiring toxic and rare elements (mostly sourced from China). Also, what are the environmental and greenhouse gas costs of manufacturing solar panels and batteries...and the eventual disposal when they wear out?

R&D and implementation should of course continue on renewables, but a full analysis in needed to determine if the entire solution will meet the desired end to fossil fuels and greenhouse gasses.
 
That really depends on where you are. In Canada, droughts will NEVER be a thing because we have more lakes than the rest of the world put together. In a lot of places though, you're right.

Well, it depends. If you're into the climate change train you'd probably be expecting droughts in Canada and floods on dry places, otherwise it wouldn't be much of a "change", wouldn't it?

Yes, that is true but disturbing a local ecosystem to save the entire planet seems like a bargain to me. This is why I think that the ultimate solution is geo-thermal.

So, you're ok with doing a known bad thing in the hopes that I'll somehow "help somewhere else". In other words, how are you helping to prevent climate change damage to a river that you already damaged to prevent climate change? You're sacrificing known valuable stuff in the hopes that something that's yet to be known will be better, or do you know quantitatively how much a hydro helps to prevent climate change?

This is why the climate change movement has so many contact points with a cult. Just apply some introspection and think: "are we the baddies?"
 
I wouldn't mind the nuclear option if they started transitioning away from the use of Uranium and into Thorium and Molten Salt reactors instead where you can actually burn up traditional reactor waste and then there's no need for expensive disposal options. but for place that have abundant geothermal options like say New Zealand, Hawaii, Iceland, USA, that's probably a better option
 
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