Research makes solar cells more affordable

KENSINGTON, Australia, May 3 (UPI) -- Australian scientists say they have boosted the efficiency of solar cells, paving the way for more affordable solar energy.

Nearly half of the cost of solar cell technology is due to the high price of the silicon used to convert sunlight to electricity. In an effort to reduce cost some scientists have moved from using expensive thick silicon wafers to cheaper thin film cells containing less silicon.

The disadvantage of such films is that they convert only 8 percent to 10 percent of incoming sunlight into electricity, compared with the 25 percent efficiency of thicker, more expensive, silicon wafers.

Now University of New South Wales researchers, led by PhD student Supriya Pillai, have reported a 16-fold enhancement in light absorption in 1.25-micron thin-film cells for light with a wavelength of 1,050 nanometers.

"Most thin-film solar cells are between 8 and 10 percent efficient," said study co-author Kylie Catchpole, "but the new technique could increase efficiency to between 13 and 15 percent."

The breakthrough, which could drop the price of an installed solar system for an average house from around $20,000 to $15,000, is reported in the upcoming issue of the Journal of Applied Physics.