Louisville startup secures $2 million funding for copper paste that may lower cost of solar

Bert Thin Films, a University of Louisville research-backed startup, secured $2 million in funding to further development of a technology meant to make solar power more accessible. 

The funding comes from a $1 million grant from the U.S. Department of Energy and $1 million in angel investment, which the startup will use to further develop its copper-based paste technology, called CuBert. The company plans to use the new funding to further de-risk the technology for the manufacturers. The DOE grant, received in late 2021, is part of a federal program meant to help integrate clean energy sources into the US electrical grid.

“Silver is a huge issue for the industry because the price volatility and there may not be enough to produce the amount of solar panels needed,” said Thad Druffel, theme leader for solar manufacturing R&D at UofL’s Conn Center for Renewable Energy Research. “We can solve it by changing one simple ingredient.”

The paste, which was invented and patented at the University of Louisville in Kentucky, can replace silver components currently used in solar panels, making them less expensive to manufacture. The paste is can replace the silver paste directly into the existing manufacturing process and equipment in use today by solar panel makers, according to the company. Druffel invented the technology with former post-doctoral research associate, Ruvini Dharmadasa, and now is CEO of Bert Thin Films.  He believes that by replacing silver components with CuBert paste, manufacturers can reduce their production costs significantly, which would reduce the cost to consumers.

With reduced costs, Druffel said, solar panels could become a more accessible and economical choice for consumers.