Solar Powered Chemical Processing

evileconboy writes "I found a great story about the creation of artificial porphyrin-based molecules that can absorb light like chlorophyll. The molecules absorb photons from porphyrin "antannae" charging a buckyball which acts like an acceptor. Apparently, the scientists want to use the molecule to drive other reactions. But I wouldn't be surprised if they could create a type of efficient, artificial leaf-like solar panel with these molecules. Forget silicon or other gallium based photovoltaic cells! "

Comments

Yes!

[konstant]

This is just the sort of thing I want to hear. Embed those puppies in my skin! I want to be green and foodless by the year 2020 goddammit!

But seriously, this is great news. Considering the shamefully small amount of money that goes into researching renewable sources of energy, I'm always delighted when they hit a new breakthrough. Solar is especially attractive - imagine running your entire home off a refrigerator-sized panel adhered to the roof. Total personal independence!

Unfortunately, there are severe limits at the moment. I recently looked into roofing a home with solar panels. Turns out that it would cost around $20k to be self-sufficient (and then only just barely). I worked it out, and it seems that with my monthly electricity costs, it would take me 103 years to pay that off.

http://www.mcn.org/a/mendom otive/Products/Unisolar2.htm

The trouble is that even the theoretical output of solar cells is low. It's bounded severely by the surface area because of the limitations of the diode materials available to us today. Turns out that even if you have full light shining on the surface, you can only get about 29% efficiency - and that's theoretical. In reality, it's less. Here's a site that explains the technical details:

http://www.nrel.gov/ncpv/documents/ pvpaper.html

Now, I have heard some clever ideas for increasing the efficiency. For example, one team discovered purely by accident that they could increase surface area by making the silicon layer extremely "spikey" on a microscopic level. The sunlight bounces around inside the spikes and is more likely to ultimately by trapped by a cell.
I think the theoretical number they cited was 40% efficiency, but right now that's still vaporware.

I wonder whether some slashdotter is brave enough to post the original ACS paper. I don't have access. I'd love to see what efficiency numbers these people are touting. Anybody?


-konstant