Analytical study on daylight harvesting potential for manufacturing facilities: Techno-economic-environmental perspective

The manufacturing industry is currently undergoing a significant transition towards electrification, prompted by the urgent need to reduce carbon emissions and embrace sustainable practices. Among the crucial areas that warrant attention, the usage of electricity for lighting stands out as an important contributor to a facility's overall energy consumption, accounting for roughly six percent of facilities' energy consumption. The proposed methodology aims to provide a holistic evaluation of the potential enhancements in energy efficiency, cost reduction, and sustainability that can be realized through the adoption of energy-efficient lighting technologies, especially in regard to daylight harvesting systems. Industrial energy consumption data from a manufacturing facility are obtained from on-site energy audits provided by the U.S. Department of Energy's Industrial Assessment Program. A daylight harvesting model is developed to facilitate prediction of energy and emission savings accrued from the proposed daylight harvesting model. The results indicated that savings from the installation of LEDs and daylight harvesting systems at the audited facility have the potential to reduce electricity consumption and CO2 emissions by 11.7%, and the total annual utility costs by 6.3%. Additionally, results indicated that daylight harvesting savings depend more on the window-to-floor ratio and room depth than orientation. Greater window area or lesser depth correlated with increased potential savings, but exceptions suggest other factors, like the number of lights within an area, also influence potential savings. The developed methodology can pave the way for manufacturers to explore the integration of daylight harvesting systems, alongside LEDs and occupancy sensors, as part of their broader energy efficiency initiatives.