Latest achievement is 40.7% in 2006 so the trend is continuing.
The solar vs. wind thing is silly since we need both (we can't do only wind). Photovoltaics are still a long way from being competitive, but as the costs are going down all the time, this is all the more reason to support them in all ways (from funding research to subsidising construction and operation).
So all in all I'd say according to published numbers concentrated solar PV can already be cheaper than wind (unless I did misundertand something :). Of course we should do both, but there's no reason to dismiss photovoltaics.
Of course we should do both, but there's no reason to dismiss photovoltaics.
This post was about updating the "we're not there yet on solar PV techno for plants on a cost basis" line to the latest developments.
Now, from the link you provided:
July 30, 2007 From 40.7 to 42.8 % Solar Cell Efficiency University of Delaware-led team sets solar cell record, joins DuPont on $100 million project. Newark, Delaware [RenewableEnergyAccess.com] Using a novel technology that adds multiple innovations to a very high-performance crystalline silicon solar cell platform, a consortium led by the University of Delaware (UD) has achieved a record-breaking combined solar cell efficiency of 42.8 percent. The current record of 40.7 percent was attained in December 2006 by Boeing's Spectrolab, Inc. [...] Barnett and Honsberg said that reaching the 42.8 percent mark is a significant advance in solar cell efficiency, particularly given the unique small and portable architecture being used by the consortium and the short time--21 months--in which it was developed. Honsberg said the previous best of 40.7 percent efficiency was achieved with a high concentration device that requires sophisticated tracking optics and features a concentrating lens the size of a table and more than 30 centimeters, or about 1 foot, thick. The UD consortium's devices are potentially far thinner at less than 1 centimeter. "This is a major step toward our goal of 50 percent efficiency," Barnett said. "The percentage is a record under any circumstance, but it's particularly noteworthy because it's at low concentration, approximately 20 times magnification. The low profile and lack of moving parts translates into portability, which means these devices easily could go on a laptop computer or a rooftop." [...] In November 2005, the UD-led consortium received approximately $13 million in funding for the initial phases of the DARPA Very High Efficiency Solar Cell (VHESC) program to develop affordable portable solar cell battery chargers. [...]
From 40.7 to 42.8 % Solar Cell Efficiency
University of Delaware-led team sets solar cell record, joins DuPont on $100 million project. Newark, Delaware [RenewableEnergyAccess.com]
Using a novel technology that adds multiple innovations to a very high-performance crystalline silicon solar cell platform, a consortium led by the University of Delaware (UD) has achieved a record-breaking combined solar cell efficiency of 42.8 percent. The current record of 40.7 percent was attained in December 2006 by Boeing's Spectrolab, Inc.
[...] Barnett and Honsberg said that reaching the 42.8 percent mark is a significant advance in solar cell efficiency, particularly given the unique small and portable architecture being used by the consortium and the short time--21 months--in which it was developed.
Honsberg said the previous best of 40.7 percent efficiency was achieved with a high concentration device that requires sophisticated tracking optics and features a concentrating lens the size of a table and more than 30 centimeters, or about 1 foot, thick. The UD consortium's devices are potentially far thinner at less than 1 centimeter.
"This is a major step toward our goal of 50 percent efficiency," Barnett said. "The percentage is a record under any circumstance, but it's particularly noteworthy because it's at low concentration, approximately 20 times magnification. The low profile and lack of moving parts translates into portability, which means these devices easily could go on a laptop computer or a rooftop."
[...]
In November 2005, the UD-led consortium received approximately $13 million in funding for the initial phases of the DARPA Very High Efficiency Solar Cell (VHESC) program to develop affordable portable solar cell battery chargers.
So they pushed from 37% efficiency in 2005 (end of wikipedia table) to 42.8% in less than three years on 13 millions USD funding (aka peanuts), plus the stuff need far less sun concentration which means less temperatures and other issues.
ThatBritGuy should send them a postcard :).
http://www.renewableenergyaccess.com/rea/news/reinsider/story?id=49617
Kenya, not a place that comes readily to mind as a PV leader is, in fact, just that. With roughly 30,000 small (truly small, 20-100 watts, not kilowatts, per household) systems sold per year, has the world's highest household solar ownership rate.
Interesting!
http://en.wikipedia.org/wiki/Betz%27_law
http://www.windpower.org/en/tour/wres/betz.htm
states that it is not possible to capture more than 16/27 -which is roughly equal to 59.3%- of the wind blowing through a wind turbine kinetic energy.
I have read in
http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0471489972.html
that modern wind turbines do achieve peak efficiency rates higher than 50-53%, close to the limit fixed by physics. Does anyone know of a similar physical ceiling for solar-derived energy?
Prospects for photovoltaic efficiency enhancement using low-dimensional structures Martin A Green 2000 Nanotechnology 11 401-405 doi:10.1088/0957-4484/11/4/342 Abstract. The use of photovoltaic solar cells provides an elegant way of converting sunlight to electricity. The photovoltaic industry is currently growing very rapidly, at a compounded rate of about 30% each year. Energy conversion efficiency is a key parameter with this technology since it directly impacts both material and deployment costs. The performance of the traditional bulk semiconductor solar cell is limited to about 33% while thermodynamic limits on the conversion of sunlight to electricity are much higher, at 93%. Low-dimensional structures appear capable of allowing much of this gap to be bridged. These structures allow increased flexibility with traditional efficiency enhancement approaches such as those based on `stacked' or tandem cells, which double efficiency limits to 68%. Perhaps more interestingly, they offer scope for completely new device concepts such as those relying on excitations between multiple energy bands and improved `hot-carrier' cells, that offer scope for similarly high performance.
Martin A Green 2000 Nanotechnology 11 401-405 doi:10.1088/0957-4484/11/4/342
Abstract. The use of photovoltaic solar cells provides an elegant way of converting sunlight to electricity. The photovoltaic industry is currently growing very rapidly, at a compounded rate of about 30% each year. Energy conversion efficiency is a key parameter with this technology since it directly impacts both material and deployment costs. The performance of the traditional bulk semiconductor solar cell is limited to about 33% while thermodynamic limits on the conversion of sunlight to electricity are much higher, at 93%. Low-dimensional structures appear capable of allowing much of this gap to be bridged. These structures allow increased flexibility with traditional efficiency enhancement approaches such as those based on `stacked' or tandem cells, which double efficiency limits to 68%. Perhaps more interestingly, they offer scope for completely new device concepts such as those relying on excitations between multiple energy bands and improved `hot-carrier' cells, that offer scope for similarly high performance.
google on "limits to photovoltaic efficiency" has many links. There are mentions of a "Shockley Queisser" framework for maximum efficiency.
