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OK, since this is a solar photovoltaics post:

Someone is going to claim that solar will never be practical, because it is 10 - 15% efficient, while internal combustion, etc. is 30%+. Please, consider that you have to *buy the energy* that goes into that 30% efficienct machine, while the 15% efficient solar panel gets it all free - then run the numbers. The only cost that matters is the dollars per Watt capital cost of the cells upfront (which is still too high, but coming down.)

Someone is going to claim that solar panels produce less energy over their lives than it takes to manufacture them. This has not been true for about 40 years.

Someone is going to claim that solar panels are a toxic danger to human health. Please consider that they are manufactured using identical processes to microprocessors, are easier to disassemble for recycling, and last 20 - 30 years plus, as compared to the five year or so length for most consumer electronics.

Someone is going to claim that solar only makes sense in certain parts of the United States. Keep in mind that, for instance, Albany, NY gets 80% of the solar radiation of Reno, NV. Since you pay twice as much for electricity in Albany, solar panels actually make more sense there. (Remember, most solar panels go on rooftops and spin meters backwards - you get retail price ($.08 - $.15 / kWh,) not wholesale ($.02-$.04) like a power plant.

Someone is going to claim you would have to blanket the desert with solar panels to make a workable power plant. Is this what you do with a distributed, smart, resource, that can occupy unused roof space anywhere? Did we take all of our microchips and assemble them into one giant supercomputer in the desert? Solar panels belong in a distributed network of generators - at the end of the wire, and putting them there is cheap and practical.

Someone is going to claim the solar industry can never meet real-world power demands. Check any industry publication for an interesting statistic - in 1996, 100 megawatts of solar were manufactured. Jan - Dec. 2004 saw about 1100 MW (about $ 6 billion worth) manufactured. Still pretty small, but an amazing growth rate.

What does solar cost now? About 1/20 what it did in the 1970s, but still about twice as much as grid electricity. Once you buy the panels, and finance them with, say, a home equity loan, you're looking at $.18 - $.25 /kWh. Getting closer every year, but still not quite there.

To be a real power generation source, they need to get that lifetime up by a factor of 4 - doable with the right encapsulants, some chemistry, getting rid of liquid electrolytes, etc. I bet one of these poeple will be at $.10 / kWh in five years - but the conventional silicon cells can probably get there in about 8, with manufacturing and scale improvements. So it's a real race...we'll see who pulls it out.

Yeah, this is definitely wrong.

Peak ncident solar radiation is typically ~ 1 kW per square meter. That the article claims efficiency of 12%, so the 120 watts is per square meter (under strong sun). It's interesting to me that this thing delivers at 110V.

Affordable solar has been on the horizon for a long, long time. There's a good amount of activity at present (Konarka is another interesting company); let's hope someone is actually able to deliver soon.

Also, let me pre-emptively respond to a few posts that I know we'll see:

- solar energy is transient, but if it's cheap enough, you can (gasp!) store the energy- compress air, lift water, etc.

- if the efficiency is high enough, you can generate a significant portion of U.S. electrical demand with solar.

To wit:

Annual U.S. electrical consumption: ~ 3.6 trillion kWh (http://www.cia.gov/cia/publications/factbook/geos /us.html)

Avg. daily solar insolation, U.S.: Around 5 kWh per sq. meter (http://www.windsun.com/Solar_Basics/Solar_maps.ht m)

Okay... 365 days in a year... 12% efficiency... that works out to 16 billion sq. meters of panels... that's 6400 sq. miles... U.S. has ~ 3.6M square miles... so you'd need to cover 0.2% of land area. So it's a matter of economics, not raw requirements.

I wonder what % of U.S. land area is rooftops & other available space.

Someone please check my math, but I've heard the '100 mi x 100 mi of panels powers the US' claim before, so I appear to be consistent with that (I arrived at 80 miles on a side).

give me 10% efficiency for a dirt cheap thin-film that I can put on my roof and I'll be happy.

I think you want to keep an eye on these guys.

Great article, but you can improve it for us with just a little bit of html, making links is not hard:

You can find it with many slides at http://online.itp.ucsb.edu/online/colloq/lewis1/

Some of the recent research, and the progress made by startup companies is summarized at:

http://www.konarkatech.com/news_articles-forbes_no v.php

http://www.konarkatech.com/news_articles-solracs-h ybPV.php

http://www.st.com/stonline/press/news/year2003/t13 55h.htm

http://www.nanosolar.com/advantages.htm

Great article, but you can improve it for us with just a little bit of html, making links is not hard:

You can find it with many slides at http://online.itp.ucsb.edu/online/colloq/lewis1/

Some of the recent research, and the progress made by startup companies is summarized at:

http://www.konarkatech.com/news_articles-forbes_no v.php

http://www.konarkatech.com/news_articles-solracs-h ybPV.php

http://www.st.com/stonline/press/news/year2003/t13 55h.htm

http://www.nanosolar.com/advantages.htm

The organic LED based technologies (polymeric / organic /nanostructured / Titania / Gratzel / Graetzel) cells are not yet ready for prime time, though they have huge promise. Check out Konarka or Nanosolar. GE and HItachi are also fooling around with this. The idea is that you can make solar cells out of TiO2, which is almost infinitely cheap in industrial quantities (see here toothpaste or white paint.)

Uni-Solar's product is in fact based on conventional silicon, just like 90%+ of the market today. The difference is that instead of slicing it out of crystals, they sputter it onto a backing, enabling them to make, e.g. peel-and-stick solar panels for commercial raised seam roofs, a conventional shingle for residential roofing, as well as, here, a flexible backing product for airships. Many are working in this area; it's sort of the next generation for solar cell cost decreases (which have come down by more than half in the last ten years; world production doubled between 2000 and 2003 - however, we're going to run out of tricks with conventional silicon within about 5 years at this pace.)

I find everyone's obsession with conversion efficiencies touching; what sense does it make when your fuel source is infinite and free? Area - related costs are subtle, so focus on this: with solar, efficiency matters not at all - the be all and end all is cost per watt.

From reading this press release, they have struck a deal with EDF (Huge french based utility provider), and my conspiracy theories might make me think that EDF's goals are not all that glamorous, when you know that they have a very big parc of nuclear power stations and promotes them heavily.

Murphy(c)

Dr. Michael Gratzel (credited with pioneering the technology in the article) has a startup in Lowell, MA that has been working towards commercializing polymer based photovoltaics since 2001 called Konarka Technologies, and from what I understand from talking to them, they're almost done. I wonder if this involves some technology license, or if STMicro is going to beat Dr. Gratzel out the door with his own technology.