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Hairy Solar Cells Could Mean Higher Efficiency
kitzilla writes "Two research groups working independently have come up with what they say are cheap processes for growing nanowires to be used with solar cells. The 'hairy' cells provide a direct path for electrons collected at the panel face to reach an electrode, something which has the potential to dramatically improve system efficiency."
solar cells are pn junctions and DO NOT Collect electrons. i am to lazy to get into solid state theory right now. so go figure how exactly pv cells work.
If every solar cell advance that was announced actually led to improvements of solar cells you could actually buy, then they would be 99.9999999% efficient and cost less than crackers.
But I'm not bitter, nooooooo.
Know what would rawk? A 5 year moritorium on new PV cell research so we could get some actual PV cell production going.
THL phish sticks
but what is really needed is a photovoltaic that will release two electrons for every photon. If any of you material guys out there do that, you'll be a gazillionaire! That will really make photovoltaics productive enough to really complete with other alternative energy source - assuming fossils fuels don't go up much higher than they are now. Photovoltaics need to get down below $0.15 kwh on the roof (the heat from a typical roof reduces photovoltaic's efficiency by at least 10%).
The problem is that a large portion of the lab performance-enhancing techniques are so insanely expensive that they *can't* go into production. Many of them - particularly exotic materials or multi-junction cells - are prohibitively expensive to make, given the meager performance improvements. I think Nanosolar has the right idea for now - craptastic cells made cheap. Who cares if they're large if they're incredibly inexpensive?
If I am not completely mistaken "classical" semi conductor cells can reach efficiencies of 40%, meaning that even with perfect 100% efficiency you would get at best a factor 2.5 improvement. Of course, 100% efficiency is an impossibility and thus I think we can safely assume that these cells will never reach more than 80%-90% efficiency, which would be an improvement of a factor of 2 over current technology. Now last estimate I saw was that in Europe solar cells work out to be about 4 times as expensive as wind power (which is itself rather pricey ), so even assuming the 100% efficiency, efficiency gains alone cannot make solar economical.
Add in to this that a large part of the cost of solar is the energy needed to produce the cells, which means that if you get that energy from a more expensive power source, the price of the cells will increase. I.e, if one started to replace relatively cheap generation capacity with more expensive solar cells, then the cost of energy, and hence the cost of the cells, would increase.
It would therefore appear to me that for solar to have a chance to become competitive what is needed is focus on lowering the cost of producing the cells, because the gains from improving their efficiency cannot offset their presently large price, and it appears unlikely that pushing for higher and higher efficiencies will be possible without making the cells more expensive.
Thermal solar is the lowest costs of all AE except for hydro. At this time, it is the same costs as a recent coal plant i.e. a plant that is cleaner than average. Of course, the solar thermal is clean all the way around.
In addition, it is fairly easy to store the heat in salts and generate during the night. Spain, Arizona, New Mexico, Northern Africa, etc. are all headed in GW size of solar thermal. Spain expects to sell power back to its northern neighbors at a tidy profits. Arizona has a 1/4 GW install going in. In addition, another group is close to building a 1/2-3/4 GW in NM or southern CO (possible to take advantage of 3 different power companies and 5 states incentives).
All in all, the only joke is a fool like you.
Polar bears make very poor harry solar solar collectors. Their white fur has a very high albedo and their high latitude habitat results in high Angle of incidence. Generally speaking, grizzlies and black bears are a much better choice of harry solar collectors given their fur color and more equatorial habitat. So the correct solution is to hunt down all the grizzlies and black bears for their skins to make super efficient solar panels so that we can stop the global warming and thus save all the polar bears. There is also the case of the ghost bears, but I'm not clear on their IR albedo.
These guys are scammers ... it's the old When Hairy Met Sili Con.
The higher the technology, the sharper that two-edged sword.
Wake me up when there's actually a cheap product. These articles need their own icon; maybe Bigfoot, the Easter Bunny, Santa Claus, the Loch Ness Monster, or La Chupacabra.
I swear to God...I swear to God! That is NOT how you treat your human!
Hairyness makes everything better. I mean, just look at me...
Nuclear always comes up in discussions like this. The answer for nuclear is to put as much effort into research as is going into solar research - instead the money has gone into lobbying to build antiquated plants. If more research was done pebble bed might be furthur along, accelerated thorium might be at the full prototype stage and synrock might have been developed in less than thirty years. Note that the three major developments come from South Africa, India and Australia on fairly small budgets from begrudging governments - think what the USA could have done on venture capital alone. There should be more to civilian nuclear energy than 1960s white elephants painted green.