Simulation of Daylight and Artificial Lighting Integration and Energy Savings

Simulation of Daylight and Artificial Lighting Integration and Energy Savings

Sutapa Mukherjee 

Assistant Professor, Electrical Engineering Department B.P. Poddar Institute of Management & Technology, Kolkata-700052, INDIA

Corresponding Author Email:
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This paper aims to find out integrated lighting simulation, the contributions from both the daylighting system and from the artificial lighting system are simultaneously taken into account. The concept behind this integrating lighting system is that the light output of individual luminaire mounted over a region of working plane is to be controlled according to the available daylight in that particular region. Any luminaire can be kept off when daylight is sufficient or can be operated at different dimming level and even at full glow when available daylight is less or insignificant. The adequacy of daylight availability is judged on the basis of desired average illuminance level on working plane. Here simulation is done using MATLAB coding. This paper provides information on daylight availability and the dimming levels of all artificial light sources which are set accordingly so that contribution from artificial lighting system together with available daylight meets desired lighting level and uniformity. These are demonstrated by isolux diagram and illuminance distribution for winter with north facing window orientation and local time 12 noon. Data base is generated for eight different window orientations, five local times for winter for corresponding CIE (International Commission on Illumination) SSLD (Standard Sky Luminance Distribution) identified for Roorkee.


 integrated lighting simulation, uniformity of illuminance, dimming value, isolux diagram, lighting-load, average illuminance

1. Introduction
2. Case Study
3. Results and Analysis

The author wishes to acknowledge the support received from Dr.R.Kittler and Dr.Danny H.W. Li through sending their publications which helped to complete this research.

She also likes to thank Indian Society of Lighting Engineers [ISLE] and specially to Mr.P.K.Bandyopadhyay, Past President, ISLE for providing a copy of the Report [6] published by Central Building Research Institute [CBRI] containing Indian Measured Daylight Database.


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