The effect of mechanical surface treatment on the UV-Visible Reflectance of low cost solar thermal absorber materials

The mechanical treatment of solar absorbers by rolling, surface roughening and polishing, and large scale texturing can significantly affect the absorption of solar radiation in the ultraviolet and visible range. In this study, the effect of a number of mechanical treatments was examined for a range of low cost absorber materials. It was found that mechanical deformation of the test materials by rolling had a minor impact on their reflectance characteristics. However it was found that surface roughening and the orientation of the roughness features with respect to incoming radiation had a significant effect of the reflectance of all materials.