24 August 2011
Magnolia demos high-voltage InGaAs QW waveguide solar cells
Magnolia Solar Corp of Woburn, MA and Albany, NY, USA says that its subsidiary Magnolia Solar Inc has demonstrated high-voltage indium gallium arsenide (InGaAs) quantum well waveguide solar cells, a unique structure capable of improving the performance of photovoltaic modules.
Chief technical officer Dr Roger E. Welser presented the latest technical results in ‘High-Voltage Quantum Well Waveguide Solar Cells’ at the Solar Energy + Technology Conference in San Diego, CA on 21 August as part of a special session of the 2011 SPIE Optics + Photonics Symposium focused on ‘Next Generation (Nano) Photonic and Cell Technologies for Solar Energy Conversion’. The work has been performed in collaboration with colleagues at the Rensselaer Polytechnic Institute (RPI), Kopin Corp, the College of Nanoscale Science and Engineering (CNSE), and the New York State Energy Research and Development Authority (NYSERDA).
“The absorption of photons, and the generation of electrical current, is reduced in conventional thin-film solar cell designs. Using a waveguide to help trap scattered light inside the cell can dramatically increase the amount of current that can be generated,” says Welser. “In the past, the challenge with implementing waveguide solar cell structures has been maintaining the voltages necessary to achieve high conversion efficiency. In this work, we demonstrated InGaAs quantum well waveguide photovoltaic devices with record-high operating voltages,” he adds.
“This is a major milestone for Magnolia Solar, as we continue to make progress towards demonstrating ultra-high-efficiency thin-film solar cells,” comments president & CEO Dr Ashok K. Sood. “The aim of the work summarized in the SPIE conference is to increase both the current and voltage output of single-junction cells by using a quantum-structured active region and incorporating advanced light-trapping strategies. With this patent-pending approach, we are seeking to achieve high solar electric conversion efficiency over a wider range of operating conditions,” he adds.
“While our initial work has employed III-V materials, future efforts will also focus on lower-cost thin-film materials such as next-generation copper indium gallium selenide (CIGS) thin-film structures,” Sood continues. “We look forward to entering the next phase of development.”