Performance Indexes Assessment for Lighting Systems Based on the Normalized Power Density and Energy Losses Estimation in University Workrooms

Abstract

Well-designed lighting decreases accidents and diseases of eyes and can increase productivity and concentration. Increase of energy price and a high proportion of electric lighting energy consumption in buildings due to defects in designing and maintenance led to desirable lighting to be reduced. One of our challenges in providing health and quality of lighting is lack of economic justification of projects. Furthermore, evaluating the lighting systems is very important to improve these systems and maintaining lighting quality. In this study the performance of the various lighting systems has been evaluated. The health and quality conditions of lighting systems, energy loss and the difference between the lighting variables, based on room index and the designed required levels (normalized power density) in studied schools and education workrooms in Ahvaz Jundishapur University of Medical Sciences (south-west of Iran) have been evaluated. Results showed that the modern lighting systems had 58% more efficient than the traditional others. In other words, modern lighting systems increase illuminance to 58 percent without increasing the electrical energy power. The performance indices of lighting systems between workrooms that had modern systems and traditional was significant (p=0.000). In 77.4% of spaces of the school of Medicine, where that had new lighting systems, the satisfaction index of users was equal to one. Evaluation of lighting systems in order to decreasing the electrical energy power along with preserving the standards of illumination intensity is very important, and some appropriate solutions could be adopted by replacing the traditional systems with the new others.