Free Convection Fresnel Lenses Concentrator

Abstract

This project involves an evaluation of an improved Fresnel lenses solar energy concentrator. Its innovation consists of preventing forced convection heat losses at the receiver area. Heat losses by convection and by the transmittance and reflectance properties of the solar rays transmission of the material were calculated for the comparison of parabolic and Fresnel lenses solar energy concentrators. The expected efficiency of the Fresnel lenses concentrator within free convection conditions is 93%. An efficiency increment to 95% is noticed for vacuum conditions. Doing the same analysis for the parabolic concentrator the efficiency expectation is 95% within forced convection conditions. The efficiency expectations for both concentrators presents them as competitive choices for energy production. Key Terms - Free and Forced Convection, Reflectance, Thermal Efficiency, Transmittance.