Friday, January 9th, 2009
SolFocus, the Mountain View, California developer of Concentrator Photovoltaic (CPV) systems, today announced that it has raised $47.5 million in the first close of its Series C financing and appointed Mark Crowley chief executive officer. Crowley, who was named president of SolFocus in August 2008, will assume the role of CEO, while previous CEO and founder, Gary D. Conley, will continue as chairman of the board. The company aims to grow CPV deployments from 0.5 MW in 2008 to approximately 100MW by the end of 2010.
Crowley noted that this first close comes despite what is one of the most challenging funding environments in history. “Many good companies are going unfunded today; this close is strong validation from investors that our CPV systems are compelling today, and will help drive the growth of the solar industry tomorrow.” The SolFocus CPV design employs a system of reflective optics to concentrate sunlight 500 times onto small, highly efficient solar cells (see Figure). The SolFocus 1100S system is claimed to achieve >25% efficiency, using triple-junction III-V PV cells from Boeing subsidiary Spectrolab. In solar-rich regions of the world, CPV panels integrated with advanced tracking systems may soon reach levelized cost of energy (LCOE) parity with fossil fuels.
Last fall, the IEEE silicon valley chapter of the electron devices society (SVC-EDS) and Applied Materials co-sponsored a PV Tech Symposium in Mountain View, California, where Russ Jones of Spectrolab presented an overview of the company’s triple-junction technology. Spectrolab runs a Ge substrate fab in Sylmar, California that is scaling up from 100mm to 150mm wafers to allow them to fab more concentrator PV (CPV) cells in two weeks than the entire installed capacity today! CPV systems today represent only ~10 MW of global supply, but Spectrolab plans to bring capacity online by 2010 to represent ~250MW/year of power under 500X concentration.
Spectrolab currently produces its second and third generation of lattice-matched triple junction cells, starting from a Ge wafer as the substrate and bottom cell, a Ga(In)As middle cell (after a buffer layer), and a GaInP top cell. These structures demonstrate 37.5% and 38.5% efficiency, and the company’s next generation “metamorphic” triple junction should show 40% efficiency. A four-junction “inverse metamorphic” cell, with the wide-bandgap layer grown first off of the Ge, is claimed to ultimately lead to 43%.
A new Veeco E475 MOCVD reactor has been installed at the Sylmar fab, which is the first step in the conversion to 150mm diameter Ge wafer processing by 3Q10. Most of the tools in the new line will be used, allowing for significant cost-savings. Nearly all 150mm wafer process equipment was designed with robotic handling and sophisticated process recipe control by the OEM, providing greater control and generally improved yields. So Spectrolab should be able to deliver the volumes needed by SolFocus over the next few years. –E.K.
Tags: 150mm, concentrator, CPV, Ge, III-V, LCOE, MOCVD, PV, solar, SolFocus, Spectrolab