Second-surface silvered glass solar mirrors of very high reflectance

Guillaume P. Butel, Blake M. Coughenour, H. Angus MacLeod, Cheryl E. Kennedy, Blain H. Olbert, J Roger P Angel

Research output: Chapter in Book/Report/Conference proceedingConference contribution

6 Citations (Scopus)

Abstract

This paper reports methods developed to maximize the overall reflectance second-surface silvered glass. The reflectance at shorter wavelengths is increased with the aid of a dielectric enhancing layer between the silver and the glass, while at longer wavelengths it is enhanced by use of glass with negligible iron content. The calculated enhancement of reflectance, compared to unenhanced silver on standard low-iron float glass, corresponds to a 4.4% increase in reflectance averaged across the full solar spectrum, appropriate for CSP, and 2.7% for CPV systems using triple junction cells. An experimental reflector incorporating these improvements, of drawn crown glass and a silvered second-surface with dielectric boost, was measured at NREL to have 95.4% solar weighted reflectance. For comparison, non-enhanced, wetsilvered reflectors of the same 4 mm thickness show reflectance ranging from 91.6 - 94.6%, depending on iron content. A potential drawback of using iron-free drawn glass is reduced concentration in high concentration systems because of the inherent surface errors. This effect is largely mitigated for glass shaped by slumping into a concave mold, rather than by bending.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
Volume8108
DOIs
StatePublished - 2011
EventHigh and Low Concentrator Systems for Solar Electric Applications VI - San Diego, CA, United States
Duration: Aug 22 2011Aug 24 2011

Other

OtherHigh and Low Concentrator Systems for Solar Electric Applications VI
CountryUnited States
CitySan Diego, CA
Period8/22/118/24/11

Fingerprint

Reflectance
Mirror
mirrors
reflectance
Glass
glass
Iron
iron
Reflector
Silver
reflectors
silver
Wavelength
slumping
Triple System
floats
solar spectra
acceleration (physics)
wavelengths
Enhancement

Keywords

  • Concentrating
  • CPV
  • CSP
  • High reflectance
  • Mirror
  • Reflector
  • Silver
  • Solar
  • Thin film

ASJC Scopus subject areas

  • Applied Mathematics
  • Computer Science Applications
  • Electrical and Electronic Engineering
  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Butel, G. P., Coughenour, B. M., MacLeod, H. A., Kennedy, C. E., Olbert, B. H., & Angel, J. R. P. (2011). Second-surface silvered glass solar mirrors of very high reflectance. In Proceedings of SPIE - The International Society for Optical Engineering (Vol. 8108). [81080L] https://doi.org/10.1117/12.894373

Second-surface silvered glass solar mirrors of very high reflectance. / Butel, Guillaume P.; Coughenour, Blake M.; MacLeod, H. Angus; Kennedy, Cheryl E.; Olbert, Blain H.; Angel, J Roger P.

Proceedings of SPIE - The International Society for Optical Engineering. Vol. 8108 2011. 81080L.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Butel, GP, Coughenour, BM, MacLeod, HA, Kennedy, CE, Olbert, BH & Angel, JRP 2011, Second-surface silvered glass solar mirrors of very high reflectance. in Proceedings of SPIE - The International Society for Optical Engineering. vol. 8108, 81080L, High and Low Concentrator Systems for Solar Electric Applications VI, San Diego, CA, United States, 8/22/11. https://doi.org/10.1117/12.894373
Butel GP, Coughenour BM, MacLeod HA, Kennedy CE, Olbert BH, Angel JRP. Second-surface silvered glass solar mirrors of very high reflectance. In Proceedings of SPIE - The International Society for Optical Engineering. Vol. 8108. 2011. 81080L https://doi.org/10.1117/12.894373
Butel, Guillaume P. ; Coughenour, Blake M. ; MacLeod, H. Angus ; Kennedy, Cheryl E. ; Olbert, Blain H. ; Angel, J Roger P. / Second-surface silvered glass solar mirrors of very high reflectance. Proceedings of SPIE - The International Society for Optical Engineering. Vol. 8108 2011.
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