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Solar Power-Cell Breakthrough
Posted by
Zonk
on Thu Apr 05, 2007 03:31 PM
from the better-to-work-in-the-shade- dept.
from the better-to-work-in-the-shade- dept.
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."
Related Stories
[+]
Science: Solar Power Headed For 45% Annual Growth 402 comments
mdsolar writes "USA Today is running a pretty good article on solar power that gives an overview of the current state of the industry. Highlight include production costs of $1.19/Watt for First Solar, 40% annual cost reductions over the
last five years, revenues expected to triple in three years, and a prediction for 2014 as the year when solar photovoltaic power plants become cheaper than other forms of generation. From the piece: 'Like wind power, solar energy is spotty, working at full capacity an average 20% to 30% of the time. Solar's big advantage is that it supplies the most electricity midday, when demand peaks. And it can be located at homes and businesses, reducing the need to build pollution-belching power plants and unsightly transmission lines. In states such as California, with high electricity prices and government incentives, solar is already a bargain for some customers. Wal-Mart recently said it's putting solar panels on more than 20 of its stores in California and Hawaii. Google is blanketing its Mountain View, Calif., headquarters with 9,212 solar panels, enough to light 1,000 homes.'"
[+]
Method for $1/Watt Solar Panels Will Soon See Commercial Use 502 comments
An anonymous reader writes "A method developed at Colorado State University for crafting solar panels has been developed to the point where they are nearly ready for mass production. Professor W.S. Sampath's technique has resulted in a low-cost, high-efficiency process for creating the panels, which will soon be fabricated by a commercial interest. 'Produced at less than $1 per watt, the panels will dramatically reduce the cost of generating solar electricity and could power homes and businesses around the globe with clean energy for roughly the same cost as traditionally generated electricity. Sampath has developed a continuous, automated manufacturing process for solar panels using glass coating with a cadmium telluride thin film instead of the standard high-cost crystalline silicon. Because the process produces high efficiency devices (ranging from 11% to 13%) at a very high rate and yield, it can be done much more cheaply than with existing technologies.'"
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Off. The. Grid. (Score:5, Funny)
Re:Off. The. Grid. (Score:5, Insightful)
-nB
Parent
Re:Off. The. Grid. (Score:5, Insightful)
Imagine the checks they will have to pay out now that people can set up their roof as a money farm for 1/10 the cost!
That was the big problem with getting people to install solar. The initial cost was too much. We'll still have to pay for the breaker box upgrade so we can feed power back to the electric company, but at least it won't take 20 years to pay off the solar collectors now.
Parent
Re:Off. The. Grid. (Score:4, Interesting)
In the long run, we're better off with the high-efficiency Si cells.
Also, we don't have a good idea of the durability of these cells. I'm a bit concerned because of the organic nature; how stable are they? What kind of reduction in efficiency will we see over, say, 20 years?
Parent
Re:Off. The. Grid. (Score:5, Insightful)
But, I've been hearing about doped polymer based PV cells for a while (along with this 1/10th the cost and 1/2 the efficiency) and they are still not something that I've seen actually working, not to mention actually deployable for a residential application. Interesting idea, hopefully becomes something.
Parent
Re:Off. The. Grid. (Score:5, Insightful)
If I cover only the south-facing parts of my roof with current Si solar cells, I can over-produce my own households consumption comfortably by a factor of ten or so. At, say, $5k or there abouts for the installation. If there were solar cells with twice the "efficiency", I could overproduce my consumption by a factor of twenty.
And why would I want that?
"Efficiency" is typical oil-industry brainwashing. Unambiguously the mindset of a consumer of a finite, limited resource. Sunlight is unlimited - "efficiency" doesn't play a role anywhere. I don't want, nor need solar cells that can squeeze a few percent more wattage out of a square foot of roof. I want cells that are cheap, period:
If the whole installation was $500 instead of $5000, then I wouldn't care if the whole thing breaks occasionally or if its efficiency drops over time or whether I have to replace the complete thing every 5 years. I simply don't care. The only reason people keep whining about these things is because they keep thinking in terms of dense, high-power, expensive hi-tech nano-gadgets. Once you think of them as something low-grade, cheap, and abundant, there's a thousand times more surface area available than you could possibly need.
A 2kW installation on each of 100million roofs in the US would cover the entire US electricity consumption right there. But let's say you can collect for really cheap - how about the surface area of not only all the highways, but the strip between the highways as well? Imagine a couple suare meter of cells on every single high-voltage transmission line tower - not for "generation" so much as for "regeneration"; supplying just as much as is lost in transmission between two of these towers. Suddenly the grid itself is a producer, and the larger it gets the less it matters whether there's actually any power plants plugged in anywhere. Heck, they're towers - why not have a little windmill on top of each one as well? As long as you're thinking "expensive equipment that needs to be serviced" that won't fly, but if you can swing it for cheap, low-efficiency it'll be worth it and you just won't care whether the one or other one breaks occasionally.
There's no energy crisis. There has never been one and there will never be one. There's more than enough energy to go around. All we have to do is start tapping into it. Turns out that that is difficult to do in such a way as to make some few people super-rich -- and that is why it isn't done...
Parent
photobleaching (Score:5, Insightful)
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 [invitrogen.com] 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).
Parent
Re:Off. The. Grid. (Score:5, Insightful)
I know a wee bit about dyes, probably just enough to be dangerous, and one thing these people are apparently forgetting, is that so far, no one has invented an organic based dye that doesn't fade, so in this case, what will be the annual recoating costs in order to maintain the efficiency at an acceptable level?
Sorry to rain on all the parade plans, but I suspect the short lifetime might be a put off.
--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Zoe: "Sir, I think you have a problem with your brain being missing."
--Episode #2, "The Train Job"
Parent
Re:Off. The. Grid. (Score:5, Insightful)
Parent
Re: (Score:3)
Re:Off. The. Grid. (Score:4, Insightful)
Those BASTARDS!
Seriously though, it takes a lot more effort to get higher grade products. Better grade is needed for better density, quality, and reliability.
Parent
Re:Off. The. Grid. (Score:5, Insightful)
This is absurdly reductive. If you honestly believe the volume of silicon used in production is the only valid factor in price differential between chips, you're quite welcome to try replacing the RAM in your PC with sand. If not, your argument is intentional sophistry.
Parent
Re: (Score:3, Insightful)
Re:Off. The. Grid. (Score:4, Insightful)
Parent
Re:Off. The. Grid. (Score:4, Interesting)
Parent
Re:Off. The. Grid. (Score:5, Interesting)
Parent
IT ALSO DOES NOT WORK (Score:3, Informative)
Re:Off. The. Grid. (Score:5, Interesting)
Parent
Re: (Score:3)
Re: (Score:3, Informative)
Re: (Score:3, Insightful)
Compare having a properly cooked meal to having a horrible microwaved meal - the gas stove/oven easily wins on convenience. Compare the quality time spent cooking and eating good food with loved ones to having crap food in 1 minute - the gas stove/oven easily wins on quality of life.
ARGH! (Score:4, Interesting)
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.
A little about TiO2 (Score:4, Informative)
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).
Parent
Re:ARGH! (Score:4, Insightful)
Not the world, just day-to-day life as we know it.
Here's the problem with that: even if we started cutting back our CO2 output (disregarding all of the other pollution we put out that's causing us problems now) by 1% cumulative per year it would still be a long time before we stopped putting out more CO2 than the system can ordinarily handle. But the system is already overstressed, and as you point out the total amount of CO2 will dissipate only slowly. Even if we stopped emitting CO2 today, aside from that which is absolutely necessary, there would still be too much CO2 for quite some time to come.
Besides global warming, there are other excellent reasons to reduce CO2 output (and that of other undesirable emissions.) Probably the most serious issue at the moment is the acidification of the oceans. We've already been killing off oceanic algae with pollution, like oil spills. Now we're not only threatening algae, which definitely prefers a certain Ph range, but coral reefs have been hurting badly and the acidification of the ocean due to CO2 gas exchange is implicated. Oceanic algae produces the vast majority of the oxygen that we need to survive. CO2 is also toxic and even small increments in the percentage of the atmosphere it makes up causes health problems including dizziness, nausea, and general malaise. Although we can survive exposure to environments which are over the usual amount, it's not good for us - or probably any other mammal.
The point is that we really needed this technology decades ago, and we're already late on getting started using it. Putting sequestered CO2 into the atmosphere is simply a Bad Idea(tm). Anything we can do to reduce that NOW means that we're going to be in less trouble later. Since we can't immediately stop all CO2 use and we can't go back in time, the problem will get worse before it gets better.
I cannot disagree strongly enough. If we could actually follow the so-called radical agenda, which I like to call the rational agenda since we all live in the atmosphere and we will all suffer if it becomes less hospitable to human life, then it would be a positive thing. We are quite simply living beyond the means of the Earth to sustain us. The only truth in your statement comes from the fact that the "radical" environmentalists can only push the obstinate defilers of the planet so quickly. But without them asking for a certain level of change, we would be unlikely to have even the positive change we are currently implementing.
Parent
Down with the "Overrated" moderation! (Score:3, Informative)
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.
T
overstressed (Score:4, Insightful)
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.
Parent
"Gradualism" bugs me (Score:5, Insightful)
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.
Parent
Re: (Score:3, Funny)
Cutting To The Chase (Score:5, Informative)
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.
More mistakes to make (Score:4, Interesting)
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.
Parent
Re: (Score:3, Funny)
Yeah, but the entire energy requirements of Greenland could probably be handled by half a dozen Honda generators.
Re:Cutting To The Chase (Score:4, Funny)
> There is so much power streaming out of the sun.
Nah, solar power is not a good solution in a long run. Sun lasts, what? 5 000 000 000 years? We need to find a power source that doesn't run out of fuel.
Parent
Good idea but (Score:3, Insightful)
Numbers please. (Score:4, Insightful)
Coral (Score:3, Informative)
http://www.stuff.co.nz.nyud.net:8080/4017784a13.h
http://masseynews.massey.ac.nz.nyud.net:8080/2007
Not again (Score:5, Funny)
Re: (Score:3, Funny)
Efficiency? (Score:3, Interesting)
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.
Re: (Score:3, Interesting)
If porphyrin-based cells can be produced (at that efficiency) for less than 1/3 the cost of silicon cells, then they're ahead of the game on cost/watt. Absolute efficiency only matters where you're area-limited. Most houses use less energy than even 6% of the sunlight that falls on their roofs (except perhaps at extreme latitudes).
Re: (Score:3, Interesting)
If you have a cheap enough cell it is pretty easy to find somewhere to put it.
Longevity? (Score:3, Interesting)
(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.
Hmm (Score:3, Insightful)
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.
wavelength selection? titanium? (Score:5, Informative)
>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 [wikipedia.org] 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.
Energy Budget (Score:4, Insightful)
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.
Electric cars look a whole lot better now (Score:3, Interesting)
solar tech within our reach (Score:3, Informative)
The real breakthrough in solar cells - production (Score:4, Interesting)
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 [stanford.edu] 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" [businesswire.com], 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" [businesswire.com]. 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.
Re:To be precise... (Score:5, Funny)
Come on, give the editors credit for using a word larger than 4 syllables and spelling it correctly. You want it to be used in CONTEXT as well? Sheesh, there's no pleasing some people.
Parent
Re: (Score:3, Interesting)
Perhaps you meant this story:
New Solar Panel Technology Gaining Momentum [slashdot.org]Re: Light on detail -- Gratzel cells (Score:3, Informative)
The wiki mentions a Swiss 7% efficient experimental cell (using some exotic