Rebecca Saive

The silver lines that crisscross the face of solar panels are essentially metal wires. They’re necessary to channel the electric current flowing out of the cells, but they reflect about 5% of the sunlight that reaches them, creating the single biggest drain on their efficiency.

Rebecca Saive, an assistant professor in applied physics at the University of Twente in the Netherlands, has invented a novel type of “front contact” that addresses this problem, reducing the wasted sunlight and improving the performance of solar photovoltaics.

Her transparent contacts are made from silver nanoparticles 3D-printed onto the silicon layer of a solar cell, using a technique she developed that produces an extremely thin and precise triangular shape. The steeply angled sidewalls reflect arriving light toward the absorbing body of the cell like a mirror, boosting electricity output by at least 5% and lowering costs roughly the same amount.

ETC Solar—a startup Saive cofounded  with headquarters in Pasadena, California, and Rotterdam—produces a printing tool that enables manufacturers to integrate the technology into otherwise standard photovoltaics. It’s already selling the product, though the company hasn’t announced customers yet. 

Meanwhile, ETC and Saive’s academic team at the University of Twente are using the front contacts and other advances to develop even more efficient solar cells that she says could eventually lead to solar plants that produce lower-cost electricity, and even to solar-powered cars.