Enhanced absorption of thin-film photovoltaic cells using an optical cavity

• Main Authors: Hsu, Wei-Chun (Contributor), Chen, Gang (Contributor), Weinstein, Lee Adragon (Contributor), Yerci, Selcuk (Contributor), Boriskina, Svetlana V. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Mechanical Engineering (Contributor)
• Format: Article
• Language: English
• Published: IOP Publishing, 2015-05-05T17:10:08Z.
• Subjects: Article
• Online Access: Get fulltext

We show via numerical simulations that the absorption and solar energy conversion efficiency of a thin-film photovoltaic (PV) cell can be significantly enhanced by embedding it into an optical cavity. A reflective hemi-ellipsoid with an aperture for sunlight placed over a tilted PV cell reflects unabsorbed photons back to the cell, allowing for multiple opportunities for absorption. Ray tracing simulations predict that with the proposed cavity a textured thin-film silicon cell can exceed the Yablonovitch (Lambertian) limit for absorption across a broad wavelength range, while the performance of the cavity-embedded planar PV cell approaches that of the cell with the surface texturing.
United States. Dept. of Energy (SunShot Initiative Award DE-EE0005320)
United States. Dept. of Energy. Office of Science (Solid-State Solar-Thermal Energy Conversion Center Grant DE-SC0001299/DE-FG02-09ER46577)