干旱区生态环境知识资源中心(Arid): Comparison of the effect of outdoor exposure on the optical properties of solar mirrors and transparent encapsulant materials

Arid

DOI	10.2172/5283302
报告编号	PNL-4074
来源ID	OSTI_ID: 5283302
	Comparison of the effect of outdoor exposure on the optical properties of solar mirrors and transparent encapsulant materials
	Dake, L.S.; Lind, M.A.; Maag, C.R.
英文摘要	The effects of outdoor exposure on solar mirrors and transparent encapsulant materials are assessed and compared. The encapsulant materials tested included glasses, polymers and silicones. Samples of the materials were placed on stationary exposure racks in six locations that represented urban, desert, oceanside and high altitude mountain areas. Samples were removed periodically for optical characterizations. The spectral hemispherical and diffuse reflectance of the mirror samples and the spectral hemispherical transmittance and diffuse reflectance of the encapsulant materials was measured. The relative normal hemispherical transmittance of the encapsulant materials was measured. Correlations between the glass and mirror data showed that the average diffuse reflectance losses were six times larger for the mirrors than for the glass samples. The average specular reflectance losses for the mirror samples were seven times as large as the average hemispherical transmittance losses for the glass samples. These correlations may enable one to predict the performance of mirrors made using the other encapsulant materials for superstrates. It was found that the urban and oceanside sites were the dirtiest, while the desert and mountain sites were the cleanest. Average specular reflectance losses varied from 4% at the cleanest site to 50% at the dirtiest site. The range in hemispherical transmittance losses for the encapsulant materials varied between 0% and 6%. At one site, the average daily specular reflectance losses were .04% for the mirror samples and average daily hemispherical transmittance losses were about .01% for the glass samples. The polymer materials degraded somewhat more rapidly than the glasses, and the silicones irreversible degraded too rapidly and severely to be useful for either photovoltaic or solar thermal applications.
出版年	1981
报告类型	Technical Report
语种	英语
国家	美国
来源学科分类	14 SOLAR ENERGY ; GLASS ; OPTICAL PROPERTIES ; WEATHERING ; MIRRORS ; MATERIALS TESTING ; POLYMERS ; CONTAMINATION ; DESERTS ; ENCAPSULATION ; LIGHT TRANSMISSION ; MOUNTAINS ; SEAS ; SILICONES ; SPECTRAL REFLECTANCE ; URBAN AREAS ; ARID LANDS ; PHYSICAL PROPERTIES ; SILOXANES ; SURFACE WATERS ; TESTING 141000* -- Solar Collectors & Concentrators
URL	http://www.osti.gov/scitech/servlets/purl/5283302
资源类型	科技报告
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/263123
推荐引用方式 GB/T 7714	Dake, L.S.,Lind, M.A.,Maag, C.R.. Comparison of the effect of outdoor exposure on the optical properties of solar mirrors and transparent encapsulant materials,1981.