Silicon solution: Innovalight’s ink solution contains silicon nanocrystals.
“The record efficiency of a silicon solar cell is about 25 percent in the lab,” says Matthew Beard, a senior scientist at the National Lab’s Golden, CO, research center who was not involved in the testing. However, says Beard, “if they can [achieve 18 percent efficiency] at a lower cost, then that would be significant.”
Cyrus Wadia, a research scientist at the Lawrence Berkeley National Laboratory, agrees, adding that because the efficiency boost is modest, “the linchpin is the cost.” Wadia reckons that the silicon-ink printing would have to add less than 13 percent, approximately, to the total cost of the cell to be worthwhile.
The ultimate promise of silicon ink is that it could be used to make an entire solar cell, eliminating the need for a wafer altogether, says Wadia, who is developing nanomaterials with this same goal in mind.
“In principle, this is possible,” says Antoniadis, “but it will require substantially more development and time.” Innovalight has developed silicon inks that can conduct both positive and negative charges – the key materials in a solar cell. But the company is pursuing the silicon-on-silicon application first, says Antoniadis, because “we need to deliver material value in the shortest possible time.”