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The new solar coating, made from a special nanomaterial may not look like much, but it helps solar cells to be 42 percent more efficient, making them close to being cost competitive. Best of all it can be easily produced with existing infrastructure.  (Source: Rensselaer/Shawn Lin)
New coated cell 43 percent more efficient, can be easily produced with current production lines

Solar breakthroughs are relatively commonplace.  However, typically they are iterative -- small increases by a percent or two in efficiency.  Researchers at the Rensselaer Polytechnic Institute have invented a new solar cell that is anything but iterative as it blows away past offerings by a large margin; something RPI calls a "game-changer" for the solar business.

Against relatively cheap coal power, solar -- like nuclear and wind -- has struggled to compete from a purely economic standpoint.  Worse yet, it trails wind and nuclear in terms of how close it is to being cost competitive.  The light at the end of the tunnel is that solar have shown the highest gains in efficiency of any alternative energy source, making its future look very bright.

The new RPI solar cell is a normal cell covered in a special anti-reflective coating which traps sunlight from nearly every angle and part of the spectrum.  The new cell is near perfect; it absorbs 96.21 percent of the sunlight shined on it, while a normal cell could only absorb 67.4 percent.  That 43 percent efficiency boost, coupled with mass production, if properly implemented could place solar on the verge of competing unsubsidized with coal power, at last.

Shawn-Yu Lin, professor of physics at Rensselaer and a member of the university’s Future Chips Constellation describes the breakthrough, stating, "To get maximum efficiency when converting solar power into electricity, you want a solar panel that can absorb nearly every single photon of light, regardless of the sun’s position in the sky.  Our new antireflective coating makes this possible."

Most materials have a mixture of light absorbing (anti-reflective) and light reflecting properties, depending on the angle and wavelength of light.  For example, eyeglasses allow light to pass through on direct angles, but begin to reflect light at sharper angles.  Solar panels in their current form operate with similar mixed character.  In order to improve efficiency, mechanical components must be added to turn to panel to face the sun.  This system entails significant cost and loss of energy efficiency, as well as a great maintenance burden.

With Professor Lin's discovery, the world's first cost-efficient static solar arrays could be produced.  No matter what angle the sun was at, nearly all sunlight would be absorbed and converted to power.  Professor Lin describes, "At the beginning of the project, we asked ‘would it be possible to create a single antireflective structure that can work from all angles?’ Then we attacked the problem from a fundamental perspective, tested and fine-tuned our theory, and created a working device."

Rensselaer physics graduate student Mei-Ling Kuo helped Professor Lin investigate various antireflective coatings.  Their eventual choice was a nanomaterial, consisting of several fine anti-reflective sheets.  Normal antireflective coatings consist of one sheet, which absorbs light at a specific wavelength.  By stacking seven separate layers into a composite coat, they were able to absorb nearly the entire spectrum.  Furthermore, the staggered nature of the layers "bent" the flow of sunlight to a favorable angle, trapping it in the coating.  This means that if light manages to reflect off a lower layer, it will be sent back down by the upper layers.

Each layer was made from a special nanomaterial consisting of silicon dioxide and titanium dioxide nanorods positioned at an oblique angle.  The material was grown through standard chemical vapor deposition techniques, and could be applied to the manufacturing of most standard solar cells, including III-V multi-junction and cadmium telluride cells.

On a microscopic level the nanomaterial looks like a forest of tiny, densely packed trees.  Each layer is 50 nm to 100 nm thick.

The team hopes to bring their technology quickly to market, as it will require little in the way of manufacturing line changes. The research is detailed in the paper "Realization of a Near Perfect Antireflection Coating for Silicon Solar Energy", published in the journal Optics Letters.

Besides Lin and Kuo, the other researchers listed as co-authors on the paper were E. Fred Schubert, Wellfleet Senior Constellation Professor of Future Chips at Rensselaer; Research Assistant Professor Jong Kyu Kim; physics graduate student David Poxson; and electrical engineering graduate student Frank Mont.

The research was funded with the help of funding from the U.S. Department of Energy’s Office of Basic Energy Sciences, as well as the U.S. Air Force Office of Scientific Research.



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so how about actual efficiency?
By FITCamaro on 11/5/2008 10:03:17 AM , Rating: -1
Even capturing 67% of light, cells were only at best, 20-25% efficient at converting sunlight into electricity. So capturing 97% of light, they'll be what? 40% efficient?

Even if you get to 100% efficiency, you still haven't solved the problem of the sun going down or it being a cloudy day. It's been heavily overcast here for 3 days. You think we'd have the lights on still even if we had some massive battery system to handle the night time?

You still have to build nuclear or coal plants to handle times where the sun isn't up or it's really cloudy. So why build 2-3x the capacity at more than twice the cost?

Even Commifornia shot down mandating that 20% of their energy had to come from solar or wind by 2010.




RE: so how about actual efficiency?
By AssBall on 11/5/08, Rating: -1
RE: so how about actual efficiency?
By LTG on 11/5/2008 10:26:13 AM , Rating: 2
When previous record efficiencies are mentioned to be around 25%, doesn't that number already assume an optimal light angle?

If so, that means this new technology would still allow only ~25%, just at more times during the day.

I don't know which but this is a big distinction!


RE: so how about actual efficiency?
By kattanna on 11/5/2008 10:36:09 AM , Rating: 5
from my reading, even at optimal sun angle cells now only capture 67% of the light with the balance being lost and reflected out. the new coating does 2 things

at optimal angle it now captures 97%, instead of 67%

and even at non optimal angles it captures 97%, so therefore you no longer need mechanized panels that have to track the sun, instead allowing for much cheaper and easier maintenaince systems.

and since its a "simple" coating, it can be applied to existing cell manufacture lines to instantly boost them.


RE: so how about actual efficiency?
By General Disturbance on 11/5/2008 12:11:21 PM , Rating: 1
Yah, but we still have winter in the north. You still need direct incidence to get really warm.


RE: so how about actual efficiency?
By Bruneauinfo on 11/5/2008 7:01:37 PM , Rating: 2
yeah!! and what about us Matrix fanatics that are living down here near the core of the earth where it's still warm!?!?!? it's not economically feasible to tunnel to the surface to connect any of this to our power grid!


RE: so how about actual efficiency?
By jlips6 on 11/5/2008 8:49:44 PM , Rating: 2
fool, we blackened the sun anyway remember?
The robots first ran on sunlight-... wait...
QUICKLY, DESTROY THESE NEW PANELS BEFORE IT'S TOO LATE!


RE: so how about actual efficiency?
By pixelslave on 11/5/2008 9:33:44 PM , Rating: 3
quote:
Yah, but we still have winter in the north. You still need direct incidence to get really warm.


Solar panels need the light, not the warmness of the sun.


RE: so how about actual efficiency?
By AssBall on 11/6/2008 10:42:35 AM , Rating: 2
Maybe you should learn how solar panels work before you start typing. Look up INFRARED.


By TheOtherBubka on 11/5/2008 9:30:40 PM , Rating: 2
Clearing the FUD here. First, it is an accomplishment in 'extending' the angle of incidence range of anti-reflection coatings. However, in terms of increasing the efficiency of Si, all optics coating engineers will tell you a simple 1/4 wavelength anti-reflection coating will help but a 3 layer anti-reflection coating (as the authors made) is much better. For example see
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.g...
Took an InP cell and increased it's efficiency from 11.96% to 19.43%. BUT, what the authors Jason is citing here do not point out is that the processing for this type of coating is extremely expensive. Although the materials are sputtered down, the top 2 coatings of the picture have to be done at fairly oblique angles to the sputtering target where material utilization goes down and the ability to cover large areas decreases. Keep this in mind when they have had to increase the complexity substantially to accomplish what can be accomplished through other engineering methods.


RE: so how about actual efficiency?
By JLL55 on 11/5/2008 10:47:08 AM , Rating: 2
the 25% incorporates inefficiencies in the conversions and transmission IIRC. So this is trying for the lowest hanging fruit of absorption (increased absorption = increased electricity production). Similar to gas where a large percentage (anyone know the number) is lost to heat and light and inefficiency in force transfer (hence the things like microspray injection for gas engines increases surface area of gas molecules to all more efficient burning while the force transfer and heat and light inefficiency still exist.


RE: so how about actual efficiency?
By RamarC on 11/5/2008 10:38:19 AM , Rating: 5
these articles are a waste of typing! everyone knows solar will never be economically feasible just like there will never be a black US president! ;-)


RE: so how about actual efficiency?
By CommodoreVic20 on 11/5/2008 10:54:32 AM , Rating: 2
I couldn't agree more. Why keep wasting money and time in research such as this, its obviously leading no where!


RE: so how about actual efficiency?
By CyberHawk on 11/5/08, Rating: 0
By sprockkets on 11/5/2008 11:24:43 AM , Rating: 2
Maybe he/she was being sarcastic??????


By AnnihilatorX on 11/5/2008 11:44:00 AM , Rating: 4
Please turn on your sarcasm detector!


RE: so how about actual efficiency?
By kontorotsui on 11/5/2008 4:41:50 PM , Rating: 5
quote:
solar will never be economically feasible


I find your lack of faith... disturbing.


RE: so how about actual efficiency?
By mfed3 on 11/5/2008 5:41:36 PM , Rating: 1
do you know what sarcasm is


By shin0bi272 on 11/5/2008 5:42:06 PM , Rating: 2
Vader let him go!


RE: so how about actual efficiency?
By Gzus666 on 11/5/2008 10:09:06 AM , Rating: 1
Right, but you have to ignore the "Mick Spin" (McSpin? not sure on this yet, since his name sounds one way, but is spelled another, you guys choose) as I like to call it. It could still be useful for powering little gadgets and whatnot. Also just a good innovation in general. Love to see nano-sciences progressing.


RE: so how about actual efficiency?
By Moohbear on 11/5/2008 10:15:56 AM , Rating: 2
Sure, the cells work only during day time, but one can always convert and store the surplus energy under a different form (heat, hydrogen, whatever). The cells are just one part of the puzzle. Besides, I don't see anything wrong with developing better tech. Sunlight is plentiful and FREE! No costly extraction and transport like oil or coal or gas. It's like hydroelectricity or wind. It's not available everywhere all the time, but if it's there, why not use it?


By JonnyDough on 11/5/2008 10:23:51 AM , Rating: 4
There are multiple energies that come from the sun. It isn't just "light." Even on a cloudy day it is possible to get sunburn. The best solar techs will be able to achieve higher efficiency by capturing more multiple types of the sun's energies and radiation.


RE: so how about actual efficiency?
By BansheeX on 11/5/2008 12:36:30 PM , Rating: 4
quote:
No costly extraction and transport like oil or coal or gas


Don't forget that solar and wind require a lot of materials to produce, some of them exotic. Pretty sure thousands of windmills made of steel have plenty of "extraction" and "transport" and "maintenance" and "land" costs behind them. Nuclear has some of that as well, the difference is that it's a constant and friendlier power source, so the ratio of costs to power generated is 10x better with nuclear. Which makes blocking it the last thirty years look rather retarded while we inflate poor people's wages to subsidize technologies that could never hope to reach that cost efficiency even if it were sunny and windy 24/7. The real problem at the moment is not a lack of domestic energy, it's our gas powered cars. We need better battery technology pronto as well as a rapid increase in nuclear. Diverting any investment into solar or wind at this stage is a total mistake. I honestly think it's just a ruse by politicians to placate people, they only care about winning votes and looking like they're doing something.


By Moohbear on 11/5/2008 2:00:35 PM , Rating: 2
You always have a sizable investment as well as maintenance cost for a power plant, be it gas, nuclear or solar. Then you have the energy cost. A coal or gas plant will require constant supply of material to burn. A nuclear power plant will require periodic resupplying. Dams and windfarms do not.
I'm not saying wind or solar farms are cheaper to build and operate (because they're not for now), but they have a lot of headroom for lower cost and better efficiency. They're not much more you can squeeze out of a modern gas plant.


RE: so how about actual efficiency?
By eyebeeemmpawn on 11/5/08, Rating: 0
RE: so how about actual efficiency?
By wookie1 on 11/5/2008 11:31:12 AM , Rating: 2
What is "actual" efficiency? Do you mean thermal efficiency? Cost efficiency? Would it be cheaper to power your car with solar? It seems that the answer is no, because the panels that would be needed to do it wouldn't fit on the road (in a car that could actually be used for commuting and meet safety requirements, etc. I know that there are solar cars that universities race against each other). Gasoline is more cost effective even at 25% efficiency from the combustion engine.


RE: so how about actual efficiency?
By Spuke on 11/5/2008 2:27:01 PM , Rating: 2
quote:
What is "actual" efficiency?
Good luck getting an answer for this question. I've asked this many times and gotten crickets. People here don't really know what the hell they're talking about here most of the time and just throw around buzzwords. There's only a few that have good info to pass along.


RE: so how about actual efficiency?
By Schrag4 on 11/6/2008 11:59:18 AM , Rating: 2
Let's dumb it down then. Sure, it's absorbing more light, blah blah blah. But what are solar cells USED FOR!?!?!?!? Unless you're talking about electricity output, nobody cares.

So...what everone wants to know (and nobody can pin down apparently) is how much more electricity can be produced from the same solar cells when adding this coating. Nothing else matters.

Oh, and I don't need a number, I'm just pointing out that the whole argument about what efficiency 'really is' sounds an aweful lot like saying "It depends on what the meaning of the word 'is' is." I can't imagine that it would take more than one sentence to give a straight answer to the question.


By theapparition on 11/5/2008 11:41:45 AM , Rating: 4
But the topic is commercial generation of electricity. Don't know any place that uses gas to generate electricity for the grid.

Gasoline's benefit is that it packs a lot of energy in a compact space that is portable. Something that, so far, nothing else has been able to match. Per weight, a gallon of gas has the energy capacity of 120-200X current battery technology. So even with a 30% engine efficiency, it's still far more portable energy than with batteries.


RE: so how about actual efficiency?
By Chipper Smoltz DT on 11/5/2008 10:33:37 AM , Rating: 2
Lots of available options for us, the better. Sure the sun might not be shining all the time but if it's sunny the energy could be stored or the excess could be diverted to the grid.

It's funny and I know this is a crazy idea but if it's raining maybe we could collect and store energy too when each drop of rain hits some material... comparing rain drops to light photons in a way.. hahaha

Light photons are particles of light right?... are there particles for darkness too or non-light? There's none that I know of but this is due to my limited knowledge. =(

Imagine if there was, then we could utilize the solar cells at night and "darkness" cells during night... then wind turbines during windy days and nights and "rain panels" when it's raining... =))


RE: so how about actual efficiency?
By Parhel on 11/5/2008 10:41:07 AM , Rating: 5
If there are darkness particles like photons, then there might also be non-rain drops. Then, we could have non-rain panels that would generate energy whenever it isn't raining.


RE: so how about actual efficiency?
By Chipper Smoltz DT on 11/5/2008 11:04:23 AM , Rating: 2
Hahaha... =))

But what if there's something in darkness that could also be used to harness some form of energy eh....

As for the raindrops like photons of light... just wishful thinking eh? Seems like everything now could be converted to energy and stored in some device. Heck, maybe people walking can be a source of energy like if a "sidewalk" was built with pressure plates then each step on the pressure plate would be like activating something which would convert that to stored energy...


By TOAOCyrus on 11/5/2008 11:14:34 AM , Rating: 2
Yeah well darkness is the lack of light.. so no.


RE: so how about actual efficiency?
By theapparition on 11/5/2008 11:45:19 AM , Rating: 2
quote:
Heck, maybe people walking can be a source of energy like if a "sidewalk" was built with pressure plates then each step on the pressure plate would be like activating something which would convert that to stored energy...

Already done. They've taken floor panels and use piezo-electric elements to convert motion into electricity. Some universities have proposed it for sidewalks, but cost is far too prohibitive.

In fact, I think DT ran an article about some club in Europe that used similar panels that lit up as people danced on them.


By Veerappan on 11/5/2008 2:55:46 PM , Rating: 2
And while we're at it, you could probably hook up some sort of small generator to the vertical spout of your rain gutters, and use the momentum of the water that is draining to generate a few watts.

It would probably be cost ineffective, and not actually be active often, but so is the idea about using piezo-electric generators as shingles on your roof.

Of course the installation/development of the drain spout generator would cost much less than re-doing your entire roof as well.


RE: so how about actual efficiency?
By Raidin on 11/5/2008 1:04:05 PM , Rating: 2
Your rain-power idea is perfectly sound, just needs to be implemented differently. If you tried to capture the power of every rain drop on it's own, it would be very wasteful, because you'd need incredibly light material to negate as much of the force the rain drop exerts to simply move the material to create energy as possible, and you'd need to do this for as many rain drops as possible, which means an insane surface area for it to be remotely feasible or practical.

Instead, you could build a large cone to capture incoming rain and send it to a thin tube which has a paddle wheel at the end, and then you'd have yourself a mini hydroelectric power plant. =)

As far as 'dark' particles, no such thing. Light is made up of photons, darkness is made up of the lack of those photons being present. Darkness is the absence of light.

The thing most people don't usually know is that a small amount of light covering only a fraction of our planet has the potential to power the entire planet. If we get solar cells to a very high efficiency rating of light to power conversion, it wouldn't matter too much when it's dark, as the Sun will always be shining somewhere, which means power can be collected 24/7, it would just need to be distributed across the globe. This would allow virtually every solar plant on Earth to aid in powering the entire world.

Too bad we're a long way from that day.


RE: so how about actual efficiency?
By Chipper Smoltz DT on 11/5/2008 3:06:52 PM , Rating: 2
Hey thanks for the nice reply... I appreciate it. =)

I have this other weird idea... what if we could convert sound energy into electrical energy which could be stored. Just as a microphone amplifies sound by using "something" combined with an electric current.

Maybe what we could do is set up "gadgets" like these in very noisy areas and use all those noise to convert it into electrical energy and store them as well in a certain medium.

Are sound waves similar to light waves in that they are both a particle and a wave? Coz its like the inside of the human ear right? it's like a miniature thing that "vibrates" or something like that which causes us to hear sounds in the first place?


RE: so how about actual efficiency?
By Raidin on 11/5/2008 3:47:08 PM , Rating: 1
You're quite welcome.

Sound is different than light in terms of it's makeup. Sound is simply a vibration in a medium, moving as a wave. In our case, that medium is air, or the atmosphere in general.

You could theoretically set up a large sheet of super-thing, super-light material that could vibrate with any sound that passes through it (like a large version of an inner ear, and translate those vibrations to energy. problem is, most sound waves have inherently low energy potential, so you couldn't really build any useful power out of it. You'd need a lot of loud sound waves, and even then, you just might be able to power a tiny light bulb, if I am using the right scale in my head.

It's just not practical.


RE: so how about actual efficiency?
By Starcub on 11/7/2008 10:29:14 PM , Rating: 2
That "something" is a piezoelectric material. The material physically deforms due to physical stresses on the material's electronic lattice (usually due to acoustic vibration, but can be optically generated as well). As a result electrons are kicked out of the bonds and carried away by an externally applied power source. They are good signal detectors, but not good power generators.


RE: so how about actual efficiency?
By Amiga500 on 11/5/2008 11:28:53 AM , Rating: 5
Rome wasn't built in a day.

Its an improvement, a big improvement. Add it to other improvements (like bacterial hydrogen production from water) and it will become viable some day.

Just because it isn't there yet is no reason to abandon the lot.


RE: so how about actual efficiency?
By FITCamaro on 11/5/08, Rating: 0
RE: so how about actual efficiency?
By chrnochime on 11/5/2008 12:59:38 PM , Rating: 1
I haven't read up on the latest nuclear power plant technology in a long time but last time I checked, there is still that little problem of safely disposing radioactive waste which contain uranium, plutonium, amongst other radioactive elements. Limitless power from reprocessing? Not like you can infinitely reprocess the waste anyway. I never do understand how nuclear proponents can just downplay the waste disposal issue when it's still impossible to make them not substantially radioactive within even 300 years, let alone 100 years.


RE: so how about actual efficiency?
By Cuddlez on 11/5/2008 2:04:52 PM , Rating: 5
Well then start reading:

1. As a matter of fact you're right we can't reprocess it infinitely, but given the amount of Uranium we have now, using a breeder type reactor the fuel would last "several BILLION years". Not quite forever, but I'd say it's close enough. Mind you, within the next billion or so years, I'm pretty sure we'll have a working fusion reactor. Which, of course, runs off of hydrogen. And since hydrogen is the most common element in the Universe we wouldn't run out of fuel until the universe is gone. Bu by then I'm pretty sure energy production won't really matter...

2. As for reprocessing, we can (again in a breeder type reactor) reuse as much as 97% of the spent fuel. This is according to British Nuclear Fuel.

3. As for the waste, well if most of it gets re-used then there won't be as much left to worry about. And the great thing about radioactive waste... it goes away eventually! It doesn't seem like people think about it much but substances like lead, arsenic and mercury are always poisonous. They always have been, and always will be. But spent nuclear fuel, after so many years becomes relatively harmless (I wouldn't go eating it or anything).

For good info check out this website:

http://www-formal.stanford.edu/jmc/progress/nuclea...

And here are my references for points 1 and 2. Point 3 is basically my own deduction based on points 1 and 2.

1. http://www-formal.stanford.edu/jmc/progress/cohen....
2. http://news.bbc.co.uk/1/hi/uk/647981.stm


RE: so how about actual efficiency?
By Starcub on 11/7/2008 10:53:46 PM , Rating: 2
I hope the 3% of the waste that they just dump into the sea isn't radioactive. If it is, I can't see how they can claim it is ok. Security and waste disposal have traditionally been a big part of the cost of nuclear power, and it sounds like they are cutting corners to make it economically viable.


By FITCamaro on 11/5/2008 3:43:26 PM , Rating: 2
For storing what little waste is left and unused after reprocessing, we've got lots of these big, giant rock things called mountains that are useless and can be made to have plenty of space inside to store it in. Preferably glassified then stored.


RE: so how about actual efficiency?
By werepossum on 11/5/2008 6:46:31 PM , Rating: 3
quote:
by chrnochime on November 5, 2008 at 12:59 PM
SNIP
I never do understand how nuclear proponents can just downplay the waste disposal issue when it's still impossible to make them not substantially radioactive within even 300 years, let alone 100 years.

My college chemistry professor said if we really want to dispose of nuclear waste, dilute it, put in large barrels with tiny holes, and dump it in the oceans. We don't create radioactivity, we simply concentrate it, so to safely dispose of it we simply need to un-concentrate it. He also said that would be stupid, because concentrated energy will always be valuable once we have the technology to use it.

Regarding the solar efficiency invention, I think that's a really good thing. Solar, being point-of-use, has the capability to reduce generation and transmission requirements. But it needs to get a lot cheaper to be practical even for grid peak-shaving. Right now solar is nowhere near ever paying back its cost unless you get a hefty tax break - which just means using the confiscatory power of government to subsidize your toy.


RE: so how about actual efficiency?
By Starcub on 11/7/2008 11:08:09 PM , Rating: 2
quote:
Right now solar is nowhere near ever paying back its cost unless you get a hefty tax break - which just means using the confiscatory power of government to subsidize your toy.

Depends on where you live and what you can afford. Solar typically has a payback period of 10-20 years (and I'm not talking about just PV panels); however the up-front costs are expensive. That's only going to improve with subsized research. But the biggest payoffs will come from better energy storage technology.


RE: so how about actual efficiency?
By Mathos on 11/5/2008 1:24:17 PM , Rating: 2
Yeah but that old efficiency rating was based on only capturing 67% of the available light, part of the time. And due to the need to be mechanized to reach max efficiency very expensive to implement and maintain. You gotta remember though, there are no 100% efficient sources of energy.

Even internal combustion engines are at best 30% efficient in converting gas to power, due to mechanical, heat, other leakage losses. The only advantage to gas is amount of energy produced for the amount of fuel burned.

Coal or natural gas aren't exactly efficient, they lose a great deal of efficiency to mechanical loss and light loss. Though in terms of electricity production the heat energy produced is what is harvested to move the steam turbines.

And to the cloud cover thing. Yeah, cloud cover may cut down on efficiency. But, certain bands of the light spectrum penetrate cloud cover. UV is a major one, as well as infared to a lesser extent. And if they've got the panels able to capture almost 100% of the available light spectrum, that means even during heavy cloud cover they'll still capture light. Night time is always going to be an obvious short coming of solar power. But, a more efficient cost effective solar power system would prove useful, especially in the more arid area's of the world where sunlight is always abundant, as well as areas where the days last 3 months, such as Alaska or the north pole.

Also think of applications such as companies that have large flat buildings, such as factories. They could implement a solar power system on the roof's of the factories, operating of solar energy during the day, and only using conventional electricity at night, or when the output of the solar panels drops below a certain level. It would go a long way to cutting down on the carbon footprint of a lot of industries, due to using less coal power. Would also in time allow them lower overhead cost to run factories. Same could be done for many retail places. I'm sure Wal-Mart would jump on any technology that allowed them to save money by using less conventional electricity.

Not to mention they could also coat electric cars in solar electricity generating materials, allowing to be charged while driving during the day or while idle or parked. Thus, giving them longer drive ranges, and less dependency on a wall outlet or being part of a hybrid system.


RE: so how about actual efficiency?
By FITCamaro on 11/5/08, Rating: 0
RE: so how about actual efficiency?
By Parhel on 11/5/2008 4:06:16 PM , Rating: 2
I would suggest that efficiency isn't a good way to measure the usefulness of solar power technologies. For a combustion engine, the amount of fuel that goes in has an associated cost and a fixed quantity, which is why efficiency is important. For a solar panel, the fuel is free and unlimited. I would instead judge a solar panel on the power output, the size, the cost of production, the availability of the materials needed for production, the average life span, the cost of maintenance, etc. to come up with a cost per watt.

If we were to compare energy options on cost, I would assume that today's best solar panel technology would fall far short of nuclear and fossil fuels. That said, I hope our government continues to invest in solar, so that someday the technology reaches a point where solar makes sense.


RE: so how about actual efficiency?
By Keeir on 11/5/2008 5:26:34 PM , Rating: 2
Efficiency tells you the ratio of Power Output/Power Input. Since Power Input for Solar Power is some constant (depending on location) x size, efficiency ratios can give you a good indication of Power Output/Size. Two of your things to know


RE: so how about actual efficiency?
By Parhel on 11/5/2008 5:35:18 PM , Rating: 2
And I'm sure that's important to certain people, such as engineers incorporating solar panels into their products. But, where it may be useful information when comparing one solar panel to another, it doesn't help one compare solar panels to other energy technologies, such as coal.


By highlandsun on 11/6/2008 7:20:35 AM , Rating: 2
Sure it does, because it tells you how much physical area/land you'll need to match the output of some other given power plant.


RE: so how about actual efficiency?
By Doormat on 11/5/2008 4:49:33 PM , Rating: 5
The cells with this coating would be about 33-35% efficient. The absorption goes up by about 50%, to go from 67% to almost 100%.

What does this due to $/W and LCOE? Assuming panels aren't substantially more expensive than the baseline (10%?), and using 225W crystalline cells (not thin film), the $/W for the panel cost goes from $4.75/W to $3.60/W. The $1+/W reduction is a pretty big deal. Installation costs remain unchanged, so what was $7.50/W total cost is now $6.35/W.

On a small sized project (5MW) the LCOE is about $250/MWh before any state or local tax credits or other incentives. In comparison, the price for peak afternoon power in California this summer was between $125 and $175/MWh.

Once you figure that the ITC, PTC and other incentives combine for an approximate 17% reduction in cost of power over the baseline $250/MWh, the adjusted price after subsidies comes to $207/MWh.

Advances like this will keep solar on track for grid parity for sometime between 2015 and 2018. Meanwhile, solar thermal could probably hit parity sooner, maybe 2013, though growth in the area has been slower than I had expected. But that goes for most companies the past 3-6 months.

It it were to work for thin film just as well, it could be a huge boost - taking $1/W thin film cells that are 12% efficient and making them 17% efficient would be huge, reducing panel $/W to 75c/W. This would put thin film on the fast track to grid parity.

Does that answer your question?


"I'm an Internet expert too. It's all right to wire the industrial zone only, but there are many problems if other regions of the North are wired." -- North Korean Supreme Commander Kim Jong-il

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