Solar-cell manufacturer Suniva says that the U.S. National Renewable Energy Laboratory (NREL) has verified 20+% conversion efficiencies on several screen-printed silicon cells developed by the company’s R&D team in its lab.
“This demonstrates that Suniva’s advanced technologies in diffusion, surface passivation, and contacts can increase conversion efficiency, while reducing processing time and maintaining low cell cost,” says Ajeet Rohatgi, company founder/CTO and head of the Georgia Institute of Technology’s University Center of Excellence in
Photovoltaics. “Our R&D team already has a solid roadmap in place to further increase our efficiencies.”
Applying the company’s patented technology to reduce the number of steps in the production process and generate a series of cells with efficiencies over 20%, Suniva says its cells represent a world record for screen-printed cells and incorporate advanced design features that boost power output from the cell.
Suniva claims that it can create a higher sheet resistance emitter as well as enhanced surface passivation dielectrics in one high-temperature step. It fabricates narrow screen-printed contacts on the front of the cell and a high-quality surface reflector on the back. These components, combined with improved texturing methodologies, allow the cells to trap light and achieve high efficiencies, while keeping production costs low.
The company also has three new patents pending–in the areas of structural design, fabrication process, module integration, and the efficient use of low-cost heterojunction cells–which brings its intellectual property portfolio to 32 patents and patent applications worldwide.
“Our focus is to work diligently to move this exciting technology from
lab-sized cells to the production line and commercialize these cells as
soon as it is both possible and practical,” added company CEO John Baumstark. The company says that its current ARTisun cell technology
has produced a verified efficiency of 18.5% in the lab.
In recent months, Suniva has signed a wafer supply deal with REC and solar-module agreements with Solon and Titan Energy, and opened its first manufacturing line near Atlanta.
(For more on Suniva, click here to go to a recent PV-Tech blog.)
— Tom Cheyney