Estimation of Energy Saving in Educational Building fromDaylighting to Improve the Visual Comfort

Abstract

Daylight is the occupied-range of light that is appropriate to the human visual response. Thus, it cancontribute to human health, performance and productivity. Energy consumption can be reduced byimproving in energy efficiency. The study emphaseson the design of lighting system that will be energyefficient. The basic purpose of this paper describes how to reduce the mounted lighting load and improvethe illumination level as per international standards. A good lighting scheme should be based on moreenergy efficient & longer life and maintenance free equipment. In this research paper,a hypotheticalstudy space is selected for the daylight analysis on the Ecotect and the Radiance software on summersolstice and winter solstice days under over cast sky condition. Ecotect software is used to determinelighting demand inside the selected study space and the obtained data is exported on Radiance for detailedand more accurate daylight analysis. It is pragmatic that illuminance level is varied with respect to dateand time that are clearly expressed by the daily sun path and shadow range. It is also perceived that theinstalled artificial luminaries does not provide the required illuminance on the working plane andconsume more energy. The major aim of this research is to reduce the lighting load by introducingenergy efficient artificial luminaries into the room that provide the required illuminance level on theworking plane. Lumen method is used to explain the energy saving which is carried out according toexisting energy consumption compared with the proposed one. At the end cost comparison of energyconsumption and payback period is alsocalculated. This study shows that overall cost saving in energyconsumption is approximately 34.37% and the calculated payback period for the newly installed lights iscomprising of approximately 11 months.