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Solar Power-Cell Breakthrough
An anonymous reader writes "Researchers from the Nanomaterials Research Centre at Massey University in New Zealand have developed synthetic dyes that can be used to generate electricity at one tenth of the cost of current silicon-based solar panels. These photosynthesis-like compounds work in low-light conditions and can be cheaply incorporated into window-panes and building materials, thereby turning them into generators of electricity."
The power companies are gonna be pissed.
Technoli
FTFA: "Within two to three years we will have developed a prototype for real applications. "The technology could be sold off already, but it would be a shame to get rid of it now." God DAMN it. I want a product now.
Whinging aside, I found this interesting: "They are also more environmentally friendly because they are made from titanium dioxide - an abundant and non-toxic, white mineral available from New Zealand's black sand." Very funny sentence. But anyway, titanium is one of the most common metallic elements on Earth. The problems with it are that most of it is oxidized, and until recently there has not been a worthwhile electrolytic process for its refinement (I don't know if this is catching on or not.)
I still think it's just stupid not to work on a first-generation product now, and at the same time, work on making the stuff more efficient. We need this tech and we need it TODAY.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
This is a very interesting collision of physical and organic chemistry. Discoveries like this are why I (and I'm sure many others) find myself (themselves) becoming a() bigger and bigger advocate(s) of solar power every day. There is so much power streaming out of the sun. really, every single power source on the planet (save perhaps nuclear) derives from a solar process. Our beloved/lamented fossil fuels wouldn't exist without the creatures that created those fossils -- creatures who ate plants, ate something that ate plants or were actually plants themselves: plants use the sun.
;)
:)
Even hydroelectric power owes its existence to the sun. Perhaps in very ancient times evaporation didn't require a star close by due to the young, heated surface of the planet. But today's surface temperatures just won't cut it without our friendly star.
Wind power...well, I'm not really saying anything new here. Everyone feel free to cringe at the thought of the inefficiency of grain ethanol!
Basically, if you are an advocate of nuclear power as clean power, well then you should probably turn your fandom towards the biggest nuclear power plant in the solar system...of course, I've personally got no problem with some breeder and a couple dozen pebble-bed reactors - just saying
So what if we are just consuming its leftovers, with a giant picnic like that we ants can be assured of a bountiful feast of crumbs
Which brings me to my point which I had forgotten.
These researchers have taken a hint from nature's own, good-old photosynthesis. So to me, it seems as though we have cut the hydrocarbon out of the solar-food-chain. Rather than waiting a couple million years for plants to convert sunlight into food for themselves and other creatures, die off and then turn into black, sweet, sweet crude; we simply cut out the middle-men/middle-dinosaurs and make direct use of the sun's bounty.
Solar-power is the most elegant power source yet discovered. Now to harness it cleanly.
My Computer Music Tutorial Videos
Photosynthesis isn't a compound; it's a process.
the article was a bit 'light' on the details. It would be more enlightening if they had revealed even a ray of technical information. One tenth of the cost? For equal power output?
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Gratzel Cells have been around for quite some time. The trick is to get any kind of efficiency out of them. Wake me when I can buy one, I'm getting sick of seeing solar cell venture capitalist hype every two weeks.
-Ryan C.
here are the coral links. site is slashdotted right now so I dont know when it'l get cached.
t ml / Press_Releases/04-04-07.html
http://www.stuff.co.nz.nyud.net:8080/4017784a13.h
http://masseynews.massey.ac.nz.nyud.net:8080/2007
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
XXX#######
Is this the official annual "Solar Power Breakthrough" that is never heard from again?
Ahh.. I see.
I thought that currently porphyrin dye cells had an efficiency of under 6.5%... commercial silicon cells are 14-16%, while multi-junction research lab cells are getting over 40%... (but use some rare/expensive compounds).
What I like is the ability to generate electricity in less-than-ideal light conditions, but the efficiency is a concern.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
The mistakes that we have made WRT to energy is that we went to just several forms of energy. We have oil for transportation and coal for electricity (save a few countries, the majority is coal). Other than France, NO country is truly dependent on Nukes (America is 2'nd largest user at only 19%). In addition, NONE are dependent on alternative (though Greenland is heading towards geo-thermal in a big way).
So, now, you suggest that we should move PURELY to 1 form of energy? Hopefully, we will learn our lessons and just say No Thanx. I want to see alternative such as solar brought in in a BIG way, but it make good sense to continue using nukes. In addition, we should continue trying to obtain a fusion power. Somewhere down the road, either fission or fusion could be used for transportation to the planets or better other stars.
I prefer the "u" in honour as it seems to be missing these days.
(Yeah, it's been mentioned already. The article is light on details.)
What's the longevity of this stuff? Does it fade? What other degradation issues does it face? Silicon-based cells also DO degrage over time,too...at least their output diminishes somewhat. Is the rejuvenation process as easy as slopping on a new coat of paint?
Cool stuff, just curious as to what are the caveats when comparing implementation costs to traditional solar photovoltaics.
Perhaps you meant this story:
New Solar Panel Technology Gaining MomentumFirst, Ti in any form is not particulary common, and good ores with an economically valuable Ti percentage are hard to come by (though NZ and AU are were most of it is found). Our current known reserves of good Ti ore are projected to run out by mid-century, but I always buy these projections with a bit of skepticism.
That being said, the amount of Ti used in such a panel is trivial, because the layer's thicknesses are measured in nanometers and microns. Your golf clubs have as much Ti as a football field of such panels. Refining of TiO2 to Ti metal is expensive and energy intensive, and I presume it is necessary in order to make these panels, even though the panels actually use TiO2. The process is probably Ti02 ore -> Ti -> TiCl4 -> TiO2 nanostructures. This is because the TiO2 in the panels needs to be extremely pure, and TiCl4, being a gas, can be distilled. It is then mixed with water under controlled conditions to release HCl and produce the nano-particles/structures necessary for the panels.
This article seems mostly hype to me. TiO2 nanostructures along with various dies are heavily researched around the world, with thousands of published articles. Since the article has no data, I presume all that happened was that these guys beat the previous efficiency record by a whee bit. The problem with these types of cells is that the efficiency still sucks...around 5% vs 20% for a standard silicon-based cell, and 40% for top of the line multi-junction cells (which are enormously expensive and are currently used for things like satellites or the Mars rovers). In a typical silicon cell, the silicon is about half the cost of the final package (not including the inverters, installation and all that jazz, however). Therefore, even if these TiO2 and dies cost ten times less, that won't even reduce the cost by 50%...and then you need several times the acreage to collect the energy you need.
For now, and for at least another decade in the future, silicon is king. Unfortunately, it is very expensive and there is a serious demand crunch right now, driving prices even higher (though many silicon manufacturers are heavily ramping production to solve this).
There's a great typo in the article: "Dr Campbell said that unlike silicone-based solar cells, the dye- based cells are still able to operate in low-light conditions, making them ideal for cloudy climates."
For some reason, the summary didn't contain the typo. I'm disappointed.
Another poster claims a maximum efficiency of 6.5%.
What would be cool is if the waste energy wasn't in heat but just in unabsorbed wavelengths. Then we could cheaply make windows which would be a bit tinted (which we like anyways) and then daisy chain them to produce electricity. Say, in sky scrapers where it's all glass anyways.
It would be very neat if they were cheap enough that it wouldn't really matter where you put it for it to pay for itself.
Weird article. Lessee.
>Dr Campbell said that unlike silicone-based solar cells, the dye- based cells are still able to operate in low-light conditions
I'm unfamiliar with these silicone-based solar cells: are those the ones you tape on Pam Anderson's breasts?
Titanium/titanium dioxide? All the dyes they talk about are organic: porphyrins are heterocyclic aromatics that complex a metal ion in their centers. Not titanium dioxide, the compound: a metallic ion all by itself. Probably iron or magnesium. Ditto hemoglobin.
With those complaints aside, one of the neat things about using naturally produced chromophores is that, well, they're naturally produced, so we could get them in enormous quantities. Similarly, they can be tuned, so you could have ones that absorb different wavelengths of light, with high efficiency, stacked, to extract more energy out of the sunlight than a single-bandgap cell like most photovoltaics.
But essentially they're trying to replicate the behavior of plants, and rather than messing about with dyes in solution, it seems way more productive (although, clearly, harder) to try and get plant cells to do this for us: harness the ion gradients in their chloroplasts, parasitize their electric potential. Most of the machinery is already there. We just need to get the voltage potential outside the cell.
Nostalgia's not what it used to be.
Hmmm...according to his published papers this news brief is all wrong. these things get 0.14% conversion efficiency in nearly full sun. Bah.
Some drink at the fountain of knowledge. Others just gargle.
An earlier poster made an passing reference to Gratzel cells. From the Wikipedia article this does indeed appear to be what TFAs are talking about: dye-sensitized solar cells. The Ti is not part of the porphyrin dye, but is actually as the oxide, TiO2. A photon stimulates an electron to transfer from the dye molecule to the conduction band of the TiO2. (Iodine is also involved as part of the cycle, at least as described above.)
The wiki mentions a Swiss 7% efficient experimental cell (using some exotic dye) that's highly resistant to temperature degradation. Theoretical efficiency can go to 33%. TFA doesn't mention their efficiency, although their "most efficient" claim would indicate higher than 7%, anyway. Question is -- as earlier poster mentions -- how robust they are.
-- Alastair
Moderating my parent comment Overrated before it has even been up-moderated is an abuse of the moderation system. It is abundantly clear that the moderation was used in this case because someone did not agree with me, and knew that any other negative moderation would be denied in metamoderation.
The individual who did this is an enemy of slashdot, and is actively working to make the system not work - not that it needs much help, since the issues with the "Funny" and "Overrated" modes are a design problem.
The Overrated moderation provides an end-run around the system, and should be abolished.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
What is the actual %efficiency of these dyes, or a curve (especially in their claimed low light operation)? And how much energy is consumed manufacturing them (and their carrier infrastructure), other than "less than silicon"?
Photosynthesis is maximum 12% efficient - putting the current max ~25% of silicon in perspective. But silicon panels, though relatively expensive (in $ and energy) to manufacture, last so long at full efficiency that there's little energy required to maintain them, for decades, until they're expensive again in recycling/disposal. If these dyes are less stable in punishing sunlight (up to 1KW:m^2), and need costly maintenance, at lower efficiency, silicon might still be the lowest cost solution.
--
make install -not war
Great stuff, hardly news though, it just seems like the same thing as some Swiss lab has been working on for years.i cleID=0002C2E1-17B2-1508-97B283414B7F0000
Publications: http://isic2.epfl.ch/page58678.html
Some press coverage: http://www.sciam.com/article.cfm?chanID=sa025&art
Products?: http://www.solarisnano.com/solarenergy.php
I've been using the same dual bank of 660 Ahr flooded lead-acid cells in my 24 Volt off-grid system for almost twenty years, and they are still almost as good as new, mostly because I took the time to learn how to properly maintain them.
Most people only think of their battery bank(s) at the time they have to buy and install them. After that it's a case of Out of Sight, Out of Mind. Then, when the batteries inevitably fail prematurely due to improper usage and lack of maintenance, they bitch about how "useless" their batteries are.
Yes, decent batteries cost, as do the ancillaries, such as cabling, but the electronics, including high capacity pure sine wave inverters, are ridiculously inexpensive now. So let's do some very basic math based upon my own system:
2 x 12 x 2V cells = 1,320 Ahr @ C20 rate (two strings of 660 Ahr cells in parallel)
1 x 2 kVA inverter
1 x 750 Watt microwave
If I max out my inverter with a 2 kVA load* that means I'm drawing approximately 84 Amperes from my battery bank. At that rate my batteires will be completely discharged (and effectively destroyed) after 15 hours. Since the most you should ever really discharge your cells is around 50% (or less, ideally), then we halve that time to 7.5 hours at maximum load.
But in this case we're only using the 750 Watt microwave oven. Thus, 750/24 = 31.25. We'll use 32.
1320/32 = 41.25 hours to 100% discharge, or a little over 20 hours at 50%.
The above does not take into account such things as inverter inefficiencies, typically a loss of around 5-10% at most. I also haven't taken into account other loads running concurrently on the inverter, but the microwave is drawing 25% of the inverter's rated capacity, and other devices (lights, televisions, computers) are unlikely to use all the rest.
In such an expensive system as your friends, I'd conclude that the inverter is far larger than my own, say in the 4 kVA range, leaving a great deal more capacity for other uses.
There are a number of reasons why a battery bank cannot support a load: inadequately sized, charged, or damaged cells; undersized cabling; undersized inverter; dodgy connections (loose, corroded, etc)
For a $100,000 system not to be able to support the relatively small load of a microwave oven, I have to conclude that your friend's battery bank is either:
a) Grossly undersized for the loads it's expected to support,
b) Damaged or inadequately conditioned and charged,
c) Incorrectly installed and/or maintained,
d) Imaginary - you made the story up, because you're a silly little troll.
To avoid being assumed to be a "d", try supplying some actual facts next time you post on a subject such as this.
*The inverter will cope with up to 3 kVA for around 20 minutes
People have objected to electric cars in the past because the fossil fuels used to generate the electricity to charge them cancels out any supposed benefits. But if the car can get all of its power from the sun -- and recharge when it is parked -- then they suddenly *are* cheaper and more environmentally friendly.
These guys already have that technology and are about to start production. http://www.nanosolar.com/
Very good question. These are not just dyes--they're fluorescent dyes. They absorb a photon in a certain energy range, which puts and electron in an excited state. After a certain amount of time in that excited state (i.e., the "fluorescence lifetime") the electron drops back down to the ground state and emits a photon of lower energy (the difference in energy between absorbed and emitted photons is called the Stokes shift). Every time an electron jumps to that excited state, it can potentially react with an oxidant and destroy the fluorescence (this is known as "photobleaching." If you mix antioxidants with the dye solution you can decrease the rate of photobleaching--such an antioxidant solution is called an "antifade." There are other ways to reduce photobleaching, such as sticking certain chemical moieties onto the dye.
In short, the stability of the dye system really depends on the dye structure and the presence (or absence) of oxidizing molecules. There are plenty of fluorescent dyes used in lasers, but I don't know how long they last before bleaching. If the dye is in the right solvent (such as DMSO, perhaps) it might take a damn long time to bleach. But the point is that dye is cheap compared to refined silicon, and replacing bleached dye might be as simple as flushing out the old stuff and pouring in a new solution.
In my opinion there are only two reasonable long-term solutions to solar energy production: 1) Imitate photosynthesis using fluorescent dyes. 2) Let the plants do all the hard work of turning photons + water + carbon dioxide into sugar, then figure out how to imitate cellular respiration and turn sugar into energy (specifically, a separation of charge).
This site has tons of information about various fluorescent dyes, though it's geared towards use in molecular biology, not photovoltaics (unless you count the voltage-sensing dyes).
Si la vida me da palo, yo la voy a soportar Si la vida me da palo, yo la voy a espabilar
It's a funny thing, people everywhere always have the idea that technology will come along and save us. Some future tech will make it all better....
.....
Bah Humbug. We have everything we need right now.
solar power can be put on new homes. It just isn't.
small and quiet wind generators exist. They could be put in everyones back yard. They just aren't.
We have efficient vehicles. They're just not popular.
Most people live within 10 miles of their work. They could bike. They just don't.
We've had the tech to clean water using plants for 40 years. It's just not used.
We have the tech to build efficient homes. Instead we slap up quick and crappy ones.
Etc.
We have the tech. Tech is not the problem. The only thing holding us back now is the culture and will to do what we can already do.
Don't go looking for a miracle solution. They exist, lazy people just don't use them.
-T
P.S. I hate you all.
This article is yet another "we have a new chemistry and it's gonna be really cheap real soon now" article. Here's the real deal in solar power.
Yesterday, Mark Pinto from Applied Materials gave a talk in EE380 at Stanford on where they're going. Applied Materials is the biggest maker of semiconductor fab equipment, and they've branched out into making fab equipment for display panels and then solar cells.
To get costs down for big flat panel displays is a manufacturing technology problem. Applied Materials went at it in typical semiconductor-fab fashion - scaling up the fab size. They're now making panels of about 5 square meters in area. These are then cut up into 50-inch TV sets.
Once they got that working, they adapted the huge machinery involved to making solar panels. This turned out to work quite well. Since they're adapting a process that produces higher-quality product than a solar cell, they don't have significant quality problems. The solar-cell only makers tend to have spotty quality; he pointed out that with some solar panels, not all the cells are exactly the same color, which indicates trouble in the coating process.
With size and quality working, the next step is volume. They're about to build the first "40 megawatt fab", one that produces in a year enough solar panels to generate 40 megawatts. These are big panels, 2.2m x 2.6m. The price of the electricity produced should be just about even with peak-hour energy costs in Spain, where this is going. Energy payback (when you get more energy out than was required to make the panel) is about two years. That plant comes on line in 2008.
The next step is the "gigawatt fab", a scale-up of that plant. This is part of Applied Materials' "Solar Strategy". Their position is that the technology is here; it's just necessary to get it into volume production, real volume production. Which is what Applied Materials is good at.
Now we're talking about serious production volume. Three or four such plants could build enough solar cells to cover Southern California's air conditioning energy load in five years.
Meanwhile, they have investments in some other technologies, including a "roll to roll" flexible solar cell technology, and some exotic ideas like tinted glass windows that also generate power. But they don't need a breakthrough. The current technology is good enough to be profitable, so they can start making product and shipping it in volume, while research proceeds on lowering the cost further. Pinto pointed out that about half the cost of solar power is now installation, and that needs to move beyond "a guy with a pickup truck".
So that's what's really happening. Big machines in big factories built by big companies cranking out big solar panels in big volume. Which is how you solve big problems.
But the system is already overstressed
No one has ever demonstrated the global environment is "overstressed". We've predicted changes that might make a life a little less comfortable for one of the few species that remains entirely comfortable. But mother nature never put "comfort" on the menu in the first place. Every motile organism that ever lived began life by swimming away from its excrement, until levels of the excrement changed the local environment and then the organism begins to adapt to the nature consequence of its own success. Humans have followed the same game plan up until now that every other species has followed.
Did the cyanobacteria producing oxygen in the Siderian age give a damn about their toxic waste stream? And let's be clear here: oxygen is far more toxic to the environment that carbon-dioxide. The difference, like a bad marriage you can't function without, is that we're plenty acclimated by now to oxygen's toxic effects, except for that little detail that cancer hasn't been beaten (not yet, anyway).
The world's genetic bank proliferates designs during periods of relative stability, then prunes the non-performing accounts during periods of more rapid change. This can be defined as "overstressed", if you wish, by the same logic that every minor downturn in the national economy results in public wailing and gnashing; but equally well, could simply be viewed as the natural order of things. For every GM that puts 30,000 employees on the used car lot, a Google springs up to replace it.
I believe that mother nature is very far from having exhausted her last trick. The downside is that some of those tricks might come at humanity's expense, so we project our own stress about our own comfort onto the planet to make ourselves feel better. While we might seriously compromise our standard of living by destroying organisms that contribute to our quality of life, the planet itself would be quite comfortable spending a hundred million years or two mending its fences, following a well established three-billion-year tradition.
We have plenty of space. Are you using your roof for anything important? (Maybe you live in an apartment, so putting them on the roof never occurred to you...?) Even with today's solar panels at ~20% efficiency, people can and do power their entire homes with solar using just their roof space - although, it depends largely on how much power you use, obviously.
Even if you could only power 1/10th of your home, it would be worthwhile if it were cheaper than grid power - and that's not even considering the environmental benefits.
Space efficiency isn't really the issue with solar power. The important factor is cost.
Your number is averaged over both day and night over a year and works for southern Canada, here is a map: http://upload.wikimedia.org/wikipedia/en/7/78/Inso lation.png. As you can see from the map, much of what
is going on is that the Earth is round so that surface is tilted with respect to the average direction to the
Sun. Solar panels are tilted back towards the Sun so this compensates though there is still a larger airmass
and so a larger likelihood of having a cloud in the way. A number closer to 300 w/m^2 is a better estimate
because of the tilt. In a month of 30 days you get 32 kWh from a sqaure meter of 15% efficient silicon
solar panel. So, you want about 31 square meters of panels to handle a 1000 kWh monthly power usage. That's
about 5.5 meters on a side. You can get that much for the same that you are currently paying for grid power
at http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html and fix your rate for up to
25 years, so yes, it probably is worth it.
To be honest it isn't the cost of silicon cells that is the main problem. If that was the case we would have solar heating on every rooftop ( you just need a bit of black paint and a sheet of glass for that ). The main issue with solar power is its unpredictable nature. Even a solar cell that works in dim conditions will not extract more energy than is coming in, and this varies with the number of clouds, fog, time of the year etc... Also, solar cell's obviously don't work during the night. Then there is the missmatch between availability and demand. Most energy is needed during the winter, when there is the least sun... The breakthrough solar power really needs is the ability to store energy with low losses at a low price. Currently the only reasonably efficient way to do this is by pumping water backwards in hydroelectric dams, but then you have to deal with the losses in transporting the electricity through the grid. The suitable sites for hydroelectricity are also limited, and if they were not you would probably end up using just the hydroelectrics and not solar power. No, solar is not, at least not until cheap energy storage solutions are available, suitable for baseline power generation. It is however absolutely ideal for remote and mobile applications where refueling would be difficult and weight is a concern. You can't really put a hydroelectric dam in a comunications sattelite as an example.