Solar Cells Can Now Be Printed on Anything, even Paper and Fabric

Researchers at MIT have figured out how to print photovoltaic cells on every-day materials like paper or fabric - and the process is practically the same as printing this article out on your desk printer.

 MIT reports that a team of researchers has published a new paper in the journal Advanced Materials detailing how solar cells can be printed as easily and as cheaply as "printing a photo on your inkjet" thanks to new special inks.

"The sheet of paper looks like any other document that might have just come spitting out of an office printer, with an array of colored rectangles printed over much of its surface. But then a researcher picks it up, clips a couple of wires to one end, and shines a light on the paper. Instantly an LCD clock display at the other end of the wires starts to display the time," reports MIT news. And indeed it does look basically that simple!

The new process utilizes a brand new technique of printing -- it uses vapors instead of liquids, prints at cooler temperatures, and the printing is done in a vacuum chamber. The conditions for printing are easier on the substrates that create the solar cells, and they can be printed onto practically any old surface like untreated paper and even plastic.

What's more, the printed cells hold up through significant use -- the researchers printed a solar cell on a sheet of PET plastic then folded and unfolded it 1,000 times. The solar cell performed just as well as before it was folded at all.

Because the printing is fairly simple, and familiar in industries like packaging, the researchers believe the technology could be easily scaled up for commercial printing.

The new technology could potentially be good for the fashion designers who want to incorporate solar into clothing and accessories. Instead of a plastic-y, stiff cell on a messenger bag, the printed cells could be used and be just as flexible as if it were part of the pattern on the fabric itself. And more practically, the ability to print on paper and fabric means lighter loads for transporting solar cells, which translates to cheaper delivery of solar cells to rural areas in developing nations that need a reliable source of electricity. The printed solar cells can be coated with a laminate to protect it from the elements and still function just fine.

"We have demonstrated quite thoroughly the robustness of this technology," Bulović says in the MIT article. "[W]e think we can fabricate scalable solar cells that can reach record-high watts-per-kilogram performance. For solar cells with such properties, a number of technological applications open up," he says.

All of this sounds miraculous, but unfortunately, the printed solar cells only have an efficiency of 1%. That's way below average. The team is working to improve the materials so that better efficiencies can be reached. It's not quite ready for prime time, but it's promising.

Bron: TreeHugger