RoseStreet Labs has signed an exclusive license agreement with Lawrence Berkeley National Laboratory (Berkeley Lab) for Multi-Band Semiconductors and High Efficiency Solar Cells. This license complements and expands RoseStreet Labs' existing exclusive license for full spectrum solar cells utilizing unique multijunction technology announced April 19, 2005 with Berkeley Lab and Cornell University.
Solar cells that can capture the light from the full spectrum, that don't let any light pass through are the most efficient. The wavelength that a material can absorb is characterized by a property of the semiconductor called the band gap. By making a solar cell in layers of semiconductors, that when combined, can absorb all of the wavelengths, a very high theoretical efficiency can be obtained. In previous practice too many layers were required and finding materials with proper matching of the band gaps was difficult. In 2002 Researchers in the Materials Sciences Division (MSD) of Lawrence Berkeley National Laboratory, working with crystal-growing teams at Cornell University and Japan's Ritsumeikan University, learned that the band gap of the semiconductor indium nitride is not 2 electron volts (2 eV) as previously reported, but instead is a much lower 0.7 eV. The serendipitous discovery means that a single system of alloys incorporating indium, gallium, and nitrogen can convert virtually the full spectrum of sunlight - from the near infrared to the far ultraviolet - to electrical current. (click to enlarge image showing solar spectrum of indium gallium nitride) Solar cells made with this alloy, promise to be rugged, relatively inexpensive - and the most efficient ever created. Apparently further research in this area has led to development of solar cell materials that can be made on a practical basis, the technology that RoseStreet Labs has licensed.
RoseStreet Labs believes that these technologies can potentially achieve efficiencies above 48% in a single junction device, and encompasses a breakthrough multi-band material that may significantly reduce the complexity and manufacturing costs associated with high solar efficiencies. Both the Berkeley Lab multi-band technology and the Berkeley Lab/Cornell multijunction technologies are non-silicon based and not subject to the shortages in polycrystalline silicon materials.
These agreements support RoseStreet Labs' commercialization of full spectrum photovoltaics for terrestrial, distributed energy, military and space applications. RoseStreet Labs expects to spinout its solar operations by year end into an entity named RSL Energy. RSL Energy will commercialize the technology at its Phoenix R&D Laboratory and introduce an Intermediate Band Solar Cell product series (IBSC) with the technology. They will leverage RoseStreet Labs' Phoenix-based R&D Laboratory and its high volume semiconductor bumping foundry, FlipChip International, to produce a competitive market entry for full spectrum solar cells into the rapidly growing global renewable energy market.
Bob Forcier, President and CEO of RoseStreet Labs, said, "We are excited about the Lawrence Berkeley National Laboratory breakthrough in multi-band semiconductor materials and we believe it will lead to leapfrog advances in solar cell applications. By leveraging these disruptive technologies, we believe RSL Energy can provide a unique product solution for a broad range of renewable energy applications -- at a cost close to prevailing conventional silicon based cells, but with significantly higher efficiencies. This material set also has the potential to build devices on a variety of substrates allowing creative products in the architectural, wireless, automotive, rooftop/shingle, and distributed energy applications. We believe Dr. Wladeck Walukiewicz and his team at Berkeley Lab have invented a breakthrough scientific discovery that accelerates the concept of full spectrum solutions in the global photovoltaic markets."
RoseStreet Labs, LLC, is a supplier of products and services for wireless infrastructure in the life sciences, renewable energy and homeland security markets.
The above write-up was made by rewriting and combining material from the two press releases and the research announcements referenced below. More information about RoseStreet Labs, FlipChip International and Berkley Labs can be found at their websites, but they do not offer any more information about the solar technologies. In more depth discussion of band gap, solar spectrum and how they are used in solar cells can be found in the two research announcements.
This is yet another research development that offers tremendous potential to develop photovoltaic materials that can compete with conventional methods of generating electricity. A non-silicon single junction solar cell with an efficiency of 48% would be a major accomplishment. This research appears to be quite advanced and when combined with the manufacturing know-how of RoseStreet could lead to fairly rapid, a few years, introduction of the technology into the market place.
RoseStreet Labs, Phoenix, AZ, USA
FlipChip International, Phoenix, AZ, USA
Lawrence Berkley National Laboratories, Berkley, CA, USA
RoseStreet Labs Announces License Agreement With Lawrence Berkeley National Laboratory for Multi-Band Semiconductors and High Efficiency Solar Cells, Press Release, December 6, 2005
RoseTree Labs Announces Full Spectrum Commercialization Agreement with Cornell, Press release, April 19, 2005
Full Spectrum Photovoltaic Materials Identified, Wladek Walukiewicz, Berkley Lab
Ultra Efficient Solar Cells on the Way, Science GOGO, November 21, 2002
More blogs about solar, solar power, solar cells, energy, technology
Comments