Experimental Investigations of Solatube Daylighting System for Smart City Applications in Saudi Arabia

Abstract

The smart cities programme is at the core of Saudi Arabia’s Vision 2030. The development of smart cities is based on adapting innovative technologies and solutions to meet local needs and possibilities in order to reduce both cost and energy resources consumption. In smart cities, more than 40% of electrical energy consumption should be saved. One of the most important electrical energy saving techniques is the application of the Solatube daylight system in sustainable buildings. In the present paper, an experimental investigation into the Solatube daylight system is performed according to the local climate conditions of Taif city, Saudi Arabia. A test chamber was designed with dimensions of 1 m3, made from medium density fibreboard. The model of Solatube used in the present research is Solatube 160 DS, 10” in diameter and with a length up to 30’. The HS1010-LCD digital light meter is used for measuring light intensity. A comparison of illumination obtained from the Solatube with that obtained from artificial bulbs of standard ratings was made at two different vertical distances inside the test chamber (z = 0.8 m, z = 1.0 m). The results showed that the Solatube, at both vertical distances, gave a better illuminance than standard artificial bulbs. Moreover, the results indicated that the Solatube daylight system converted about 60% of sunlight to passive light inside the test chamber. Generally, it is concluded that the Solatube daylight system can be efficiently used in residential, commercial, or industrial buildings in smart cities according to the available solar characteristics.