Utilizing Natural Illuminance through Indoor Daylighting Systems for Green Buildings

This study explores energy-efficient passive tubular daylighting systems which utilizes natural lighting, reduce energy consumption and improve occupant well-being in buildings. For this, three passive daylighting collectors configuration of flat plate, circular dome and circular Fresnel lens were modelled using AutoCAD and SolidWorks and analysed using ray tracing software TracePro 7.3.4. The light transportation was done using a highly reflective light pipe with a reflectivity of 95%. The collectors were made from Polymethyl methacrylate (PMMA) with refractive index of 1.49 because of highly transmission efficiency, weather resistance, shock resistance, blocks UV, lightweight and cost-effective alternative to glass. The Monte Carlo ray tracing method was employed to assess the optical performance within the photometric range of 380 nm to 720 nm. The results demonstrated that circular Fresnel lens achieved better illuminance and efficiency compared to conventional systems, highlighting their potential for enhancing indoor environmental quality in green buildings.