Temperature Generation of Granular Photothermal Absorber Natural Materials Using Fresnel Lens Collector

The collector and absorberAbsorber are the two main components most influential in obtaining high solarSolar thermal performance. This study used a 30 × 30 cm Fresnel lens under a xenon lamp to improve the temperature generation performance. The materials photothermal absorbersAbsorber used are coal, andesite, and pumice, with an average granular structure diameter of 1.68–2 mm. This study aims to examine the effect of Fresnel lenses on the temperature generation performance of natural materials with granular as light trap structures and investigate which materials have the best performance. This study used an experimental method with dry and wet conditions in distilled water ( \({\text{H}}_{2} {\text{O}}\) ). The results show that the use of Fresnel lenses improves temperature generation performance. The best materials sequence in wet conditions are andesite, coal, and pumice. While in dry conditions are coal, andesite, and pumice. The heat generated has the potential to be applied to low and medium-temperature solarSolar thermal technology.