1000x shadow-free mirror-based Köhler concentrator

Hernández Sanz, Maikel and Benitez Gimenez, Pablo and Mendes Lopes, Joao and Cvetkovic, Aleksandra and Sun, Y. and Miñano Dominguez, Juan Carlos and Chaves, Julio and Mohedano, Rubén (2012). 1000x shadow-free mirror-based Köhler concentrator. In: "Proc. SPIE, Optics & Photonics - Solar Energy + Applications", 12-08-2012, San Diego (California), USA.


Title: 1000x shadow-free mirror-based Köhler concentrator
  • Hernández Sanz, Maikel
  • Benitez Gimenez, Pablo
  • Mendes Lopes, Joao
  • Cvetkovic, Aleksandra
  • Sun, Y.
  • Miñano Dominguez, Juan Carlos
  • Chaves, Julio
  • Mohedano, Rubén
Item Type: Presentation at Congress or Conference (Article)
Event Title: Proc. SPIE, Optics & Photonics - Solar Energy + Applications
Event Dates: 12-08-2012
Event Location: San Diego (California), USA
Title of Book: Proc. SPIE, Optics & Photonics - Solar Energy + Applications
Date: 10 October 2012
Volume: 8468 -
Faculty: Centro de Domótica Integral (CeDInt) (UPM)
Department: Otro
Creative Commons Licenses: Recognition - No derivative works - Non commercial

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A new design for a photovoltaic concentrator, the most recent advance based on the Kohler concept, is presented. The system is mirror-based, and with geometry that guaranties a maximum sunlight collection area (without shadows, like those caused by secondary stages or receivers and heat-sinks in other mirror-based systems). Designed for a concentration of 1000x, this off axis system combines both good acceptance angle and good irradiance uniformity on the solar cell. The advanced performance features (concentration-acceptance products ?CAP- about 0.73 and affordable peak and average irradiances) are achieved through the combination of four reflective folds combined with four refractive surfaces, all of them free-form, performing Köhler integration 2 . In Köhler devices, the irradiance uniformity is not achieved through additional optical stages (TIR prisms), thus no complex/expensive elements to manufacture are required. The rim angle and geometry are such that the secondary stage and receivers are hidden below the primary mirrors, so maximum collection is assured. The entire system was designed to allow loose assembly/alignment tolerances (through high acceptance angle) and to be manufactured using already well-developed methods for mass production, with high potential for low cost. The optical surfaces for Köhler integration, although with a quite different optical behavior, have approximately the same dimensions and can be manufactured with the same techniques as the more traditional secondary optical elements used for concentration (typically plastic injection molding or glass molding).

More information

Item ID: 20077
DC Identifier: https://oa.upm.es/20077/
OAI Identifier: oai:oa.upm.es:20077
Official URL: http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1377839
Deposited by: Memoria Investigacion
Deposited on: 24 Sep 2013 18:07
Last Modified: 22 Sep 2014 11:18
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