Air-stable selective surfaces for solar energy collectors. Final report, 1 Apr 1974--31 Oct 1975

Technical Report · Wed Oct 01 04:00:00 EDT 1975

OSTI ID:7231435

Meinel, A B; McKenney, D B; Beauchamp, W T

This report discusses progress in the design of highly selective air stable solar absorber coatings. Systematic design has been done of absorber designs employing metals and dielectrics for operation at temperatures in excess of 150C. Results of heat stability tests and measurements of the optical properties of the films at temperatures up to 600C are presented. The program demonstrated optical and thermal behavior of interference selective surfaces of the general Ag-Al/sub 2/O/sub 3/-Cr-Al/sub 2/O/sub 3/ family with cutoff wavelengths ranging from 1.2 to 2.5 micrometers, absorbtances from 0.90 to 0.95, and emittances from 0.02 to 0.04 at operating temperatures. The Helio coatings appear to be highly stable in air at 150C and probably stable to the vicinity of 300 to 350C. Evaluation of the cost effectiveness for the Helio coatings show significant value gains. The cost of deposition of Helio coatings on pipe substrates appears to be approximately half that for flat plate substrates. (GRA)

• Research Organization: Helio Associates, Inc., Tucson, AZ (USA)
• OSTI ID: 7231435
• Report Number(s): PB-252505; NSF/RANN/SE/GI-41895/PR/74/7
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000* -- Solar Collectors & Concentrators
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
CHROMIUM
COST
DEPOSITION
ELEMENTS
METALS
OXIDES
OXYGEN COMPOUNDS
SILVER
SOLAR COLLECTORS
SPECTRALLY SELECTIVE SURFACES
STABILITY
SURFACES
TRANSITION ELEMENTS