Solar Junction

About Solar Junction

Solar Junction was a venture-backed startup established to capitalize on the concentrated photovoltaics (CPV) market by developing and manufacturing high-efficiency solar cells.

The company was founded in 2007 by Jim Weldon and Vijit Sabnis and was headquartered in San Jose, California. Solar Junction's business model was centered on supplying III-V multi-junction solar cells to manufacturers of CPV systems, which use lenses or mirrors to focus sunlight onto small, but highly efficient, solar cells. The company operated as a component supplier within the renewable energy sector, aiming to make CPV a more economically viable alternative to traditional silicon photovoltaics. Its revenue model was based on the sale of these specialized semiconductor components to CPV system integrators.

The core of Solar Junction's product offering was its proprietary A-SLAM™ (Adjustable Spectrum Lattice-Matched) materials technology. This allowed for the production of multi-junction cells that could absorb a broader spectrum of light. A significant achievement came in 2012 when the company set a world record, verified by the National Renewable Energy Laboratory (NREL), for solar cell efficiency at 44% under 947 suns concentration. This technical success was a key selling point, demonstrating the potential to lower the levelized cost of energy for CPV systems. The company successfully raised over $30 million through multiple funding rounds, with notable investors including New Enterprise Associates, Advanced Technology Ventures, and Draper Fisher Jurvetson.

Despite its technological milestones, Solar Junction faced significant market headwinds. The broader CPV market for which it was developing its cells did not expand as anticipated, largely due to the rapidly falling costs of conventional silicon solar panels. This challenging market environment ultimately led to the company's acquisition in 2014 by a consortium from Saudi Arabia, including the King Abdulaziz City for Science and Technology (KACST) and its investment arm, TAQNIA. At the time of the acquisition, Solar Junction remained a U.S.-based company with its manufacturing facilities in California.