Allow me to introduce the pokeberry. You may have seen it before, whether you knew it or not, as it can grow on every continent but Antarctica and flourishes in drought and rocky terrain. That makes it an ideal candidate for cheap, locally-available dyes for solar cells. That’s why researchers at Wake Forest University believe this hearty little berry may be the secret to affordable solar power in the developing world – -regions often rife with drought and lack of fertile land for agriculture.
In a new variant of dye-sensitized solar cells, researchers at WFU’s Center for Nanotechnology and Molecular Materials found that applying a layer of pokeberry dye to their fiber-based solar cells increased light absorption and subsequently improved cell performance. The group wants to ship their fiber substrate to parts of Africa, Asia and other poor areas. There, pokeberries could easily be grown and harvested for use, and local workers could apply the dye themselves. Shipping without the dye saves money on materials and labor here, where it is expensive, and provides jobs and cheaper solar power there, where both are much needed.
The Wake researchers are the first ever to apply for a patent on fiber-based solar cells. The cells are created by stamping plastic fibers onto long, plastic sheets, forming millions of minuscule plastic “cans” that trap light and convert it to electricity. These “canny” fibers can produce up to twice as much power as current flat-cell technology and work even more efficiently when a purple pokeberry dye is added. Because the “canny” fibers create more surface area than flat solar cells, they can absorb light at any angle, from sunrise to sunset, further increasing electricity production.
FiberCell Inc., a spin-off company created by those involved at Wake Forest, has already been given license to develop manufacturing methods for producing this new solar cell. The plastic sheets the cells are stamped onto are light and flexible, providing easy production and even easier shipping, as the solar cells could simply be rolled up and shipped to developing nations. Workers at local plants would spray on the cheap, abundant dye and prepare the cells for installation.
The word is still out on numbers like conversion efficiency, degradation and other important data.