One of the drawbacks of traditional silicon-based photovoltaic cells is that they are hard. While it's possible to embed traditional solar cells in fabric, it's not an optimal situation -- the cells themselves remain solid, even if the fabric is flexible. The backing electronics required for silicon cells adds further complexity to using them as anything other than a standalone add-on for devices or buildings. But what if the photovoltaics were made of something other than silicon?
Organic photovoltaics are flexible, lightweight, and potentially less expensive than traditional solar cells (they're "organic" because they're based on carbon). The main drawback is that organic PV cells are nowhere near as efficient at converting light into electricity as silicon cells. A recent development at Georgia Institute of Technology, however, is starting to close that performance gap. By adding a chemical called pentacene to the carbon "buckyballs" (Fullerenes again!) used in making the organic solar cells, the researchers were able to boost the efficiency to nearly 3.4 percent, with signs they could get to 5 percent in the near future. This compares to 25 percent for silicon cells (and up to 50 percent for experimental materials).
Although organic solar cells aren't as efficient, their other characteristics -- flexibility, weight, ruggedness, cost -- still make them attractive. They can be more readily embedded in other materials, from fabrics to plastics to roofing, and are ideal for small, low-power projects such as remote sensors. If, a decade from now, you drive a car with solar cells on its roof to help recharge the hybrid batteries, these are mostly likely the cells you'll be using.
why are we not using the energy our own bodies produce yet?? spend a little time studying how to channel human energy and we could solve several problems.
Well Deborah, that's interesting, but none other than Bill Gates himself has patented a process of using the body as an energy conduit and carrier for the microcomputers of the future. (The Body Bus). You may find more info on this topic here: http://yro.slashdot.org/article.pl?sid=04/06/23/1513218&tid=155&tid=126
As a newbie, I don't understand all that fuss about "efficiency": what if I only convert 5-10% of solar energy? If it's enough (for the purpose at hand), it's enough! Or am I missing something?
Efficiency of a solar panel measures (in essence) how much of the Sun's power you can convert to electricity in a given amount of space. 5-10% efficiency isn't a problem if you have a lot of space to work with to get the power you need; if you don't, or if the power requirements are greater than the space available, then limited efficiency is a problem. If you're talking about (say) putting solar cells on the roofs of cars to help recharge hybrid batteries, then you want them to be as efficient as possible in order to get as much power as possible, given the limited space.
If you don't need a huge amount of power, or you have abundant space to lay out the panels, then low efficiency is less of an issue.
I spent almost a year with Michigan's solar car team. I particular, I helped out with the solar panel, did testing and stuff. So, I'm quite familiar with the normal solar cell. At least up to 2003.
But to see the cell being bent like in the picture is truly amazing!
With the typical cell, even if it were laminated, the cell would have been broken into a couple of useless pieces.
Interesting post, as always! (for a green junkie like me anyways)