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Nanotechnology Boosts Solar Cell Performance
Roland Piquepaille writes "Physicists from the University of Illinois at Urbana-Champaign (UIUC) say they have improved the performance of solar cells by 60 percent. And they obtained this spectacular result by using a very simple trick. They've coated the solar cells with a film of 1-nanometer thick silicon fluorescing nanoparticles. The researchers also said that this process could be easily incorporated into the manufacturing process of solar cells with very little additional cost. Read more for additional references and a photo of a researcher holding a silicon solar cell coated with a film of silicon nanoparticles."
It only bothers me because he linkjacks it with his blog.
If he was just posting an article, with a link to the EurekAlert post, it'd be all good. Instead, he has to post about his spammy blog, as well as his (paid?) blog on ZDnet.
The ratio of decent links to spam is 1:2 in this article.
While at Purdue one of my friends worked on a process to increase solar cell efficiency by etching TiO2 coatings into long, thin whiskers that helped 'whisk' photons down into the surface of the material. It basically doubled the efficiency of a 3% cell in the visible range. Solar hasn't taken off.
_ by_gre_1.php uses lenses to concentrate light onto small, very efficient space-grade solar panels. Each panel (if memory serves) was on the order of 1 sqcm, allowing these very expensive but very efficient (25%+) panels to be used. The overall effect was to to take 1 m2 down to 10 sqcm of chips.. and yet have the power output be about the same. Combine that concentrator technology with higher utilization of UV bands AND ultra-efficient space grade panels and you've got a winner (concentrators work ONLY in direct sun- no clouds).
Glass typically blocks UV. Most glazings contain glass. If this only boosts (and 60%, while a large number, is still a tiny increment in efficiency) the UV efficiency then there may be limited use... unless you count concentrator applications.
The "Sun Cube" (http://www.treehugger.com/files/2007/04/sun_cube
Just some food for thought.
So I RTFA, and here's the bit: "improves power performance by 60 percent in the ultraviolet range of the spectrum" and "in conventional solar cells, ultraviolet light is either filtered out or absorbed by the silicon and converted into potentially damaging heat, not electricity."
So a conventional solar cell gets ~0 energy from this part of the spectrum, but if you coat it with this special coating, it gets 60% more! And how much is that exactly?
Now if you use a different coating (2.85nm), then it improves performance "in the visible part of the spectrum" by 10%. How much energy does a conventional solar cell get from just the visible part of the spectrum? Unspecified!
That's correct, but what you failed to note is that the UV spectrum contains a much larger amount of energy than either the visible or the infrared spectra do. Shorter wavelength, higher energy. And the higher energy particles are the ones that are the most desirable anyways.
9.6%! Nothing to write home about.
As gas prices creep ever higher and coal plants become less and less desirable a partial conversion to solar power starts to become a very possible reality. Adding just one kilowatt worth of solar power to each of America's 116 million homes would reduce the power consumption almost 1/3rd. http://www.frugalfun.com/solarfest.html The system to get "off the grid" discussed my link costs a fair amount of money, and even a 1 KW system costs $10,000 right now, but if the solar panels can suddenly cost 60% less (by being more efficient) then the price of a 1 KW system could reasonably drop to $5000. Not a huge cost when you are talking about much of todays housing market. Five grand is less than the price difference between a Prius (22K) and a Ford Focus (15K). Solar might well become widespread after all, not because it is efficient, but because everything else is slowly rising to match solar power's high initial cost.
We are all just people.