Concentrated and piped sunlight for indoor illumination.
L M Fraas1, W R Pyle, P R Ryason
1Chevron Research Company, P.O. Box 1627, Richmond, California 94802, USA.
Applied Optics
|February 15, 1983
Summary
This study introduces a novel building illumination concept using sunlight. Direct sunlight piped indoors via lightguides is significantly more cost-effective than solar electricity for lighting.
Area of Science:
- Building science
- Optical engineering
- Sustainable energy
Background:
- Traditional indoor lighting relies heavily on electricity, contributing to energy consumption and costs.
- Solar energy technologies primarily focus on electricity generation, with less emphasis on direct light utilization.
Purpose of the Study:
- To present a concept for indoor illumination using concentrated sunlight channeled through lightguides.
- To evaluate the cost-effectiveness of direct solar illumination compared to solar photovoltaic lighting.
Main Methods:
- A roof-mounted solar tracking concentrator focuses sunlight into an optical fiber lightguide.
- Transparent acrylic plastic optical fibers are proposed for efficient sunlight distribution within buildings.
- A comparative cost-effectiveness analysis is performed against solar cell-based electric lighting.
Main Results:
- Advances in acrylic optical fiber transparency enable effective sunlight piping.
- The proposed system offers a direct pathway for sunlight into interior spaces.
- Direct solar illumination is projected to be approximately 25 times more cost-effective than using solar cells for electric lighting.
Conclusions:
- Directly utilizing sunlight for indoor illumination is a viable and highly cost-effective alternative to electric lighting.
- The proposed lightguide system has the potential to significantly reduce electricity demand for lighting in buildings.
- Further development in optical fiber technology can enhance the efficiency and applicability of solar-powered indoor lighting.
Related Concept Videos
01:11P-N junction
A p-n junction is formed when p-type and n-type semiconductor materials are joined together. At the interface of the p-n junction, holes from the p-side and electrons from the n-side begin to diffuse into the opposite sides due to the concentration gradient. This diffusion of carriers leads to a region around the junction where there are no free charge carriers, known as the depletion region. The charge density within the depletion region for the n-side and p-side can be described by the...
01:14Photoluminescence: Applications
Photoluminescence offers a wide range of applications due to its inherent sensitivity and selectivity. This technique allows for both direct and indirect analyses of the analyte. Direct quantitative analysis is possible when the analyte exhibits a favorable quantum yield for fluorescence or phosphorescence. However, an indirect analysis may be feasible if the analyte is not fluorescent or phosphorescent, or if the quantum yield is unfavorable. Indirect methods include reacting the analyte with...