Potential for energy savings on lighting by using fibre optics

Abstract

The effective integration of the artificial lighting system and daylight occurs only when the artificial lighting system can be switched on or off as a function of daylighting levels reaching the working surface of spaces.This article presents a methodology to assess the potential for energy savings on lighting due to the effective integration of daylight with artificial lighting in buildings. This research work considers the use of fibre optics, as a means of transporting daylight to the rear side of rooms where the supply of daylight is low. Such an approach may contribute to the reduction in the energy consumed by lighting and, at the same time, in the environmental pollution associated with buildings. The potential for energy savings on lighting by using fibre optics was found to range from 19.8% to 79.4% for seven cities in Brazil and from 56.0% to 89.2%for one city in the UK. In the study carried out in the UK, there was also a reduction in carbon dioxide emission of 122 kg per square metre of built area per year if there were integration of artificial lighting with daylight supplied by windows. Such a reduction would be 138 kg/m2 per year if fibre optics were considered in the integration.