From time to time the National Renewal Energy Lab (NREL) reminds us that the US used to be a leader in innovation. This time it’s in the area of solar thin film technology. The goal with solar thin film technology is to surpass the efficiency level of silicon solar cells. Efficiency refers to the rate at which sunlight falling on a solar cell is converted to electricity. Silicon has been the most efficient material, but it is is expensive and limited, so the world is seeking alternatives. (Picture above from the Dept. of Energy shows thin film manufactured by Iowa Thin Film Technologies.)
NREL has set a new world record using CIGS (copper indium gallium diselenide) thin film, which in tests has reached 19.9 percent efficiency, coming very close to the 20.3 percent level of multicrystalline solar cells.
“The ‘thin film’ term comes from the method used to deposit the film, not from the thinness of the film: thin-film cells are deposited in very thin, consecutive layers of atoms, molecules, or ions. Thin-film cells have many advantages over their ‘thick-film’ counterparts. For example, they use much less material—the cell’s active area is usually only 1 to 10 micrometers thick, whereas thick films typically are 100 to 300 micrometers thick. Also, thin-film cells can usually be manufactured in a large-area process, which can be an automated, continuous production process. Finally, they can be deposited on flexible substrate materials.” — U.S. Department of Energy
Now, if we only had some government policies that would help spur product development based on NREL’s cool innovation…..