الفهرس 
part 1Only 14 pages are availabe for public view
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Abstract
Meeting the challenge of sustainable living in a world with fast-diminishing finite resources; calls for a fundamental change in the way we use those resources. Our earth is rich in many natural resources that gifted from God to humankind to suffice almost of their needs. Sun is the ultimate source of natural, clean, and free light. The use of renewable energy to power our modern lives is intended to prevent the need for damaging fossil fuels and hence slow or halt global warming. Furthermore; relying on natural light to illuminate our interiors is a good opportunity to have a healthy indoor environment, a clear atmosphere, and a great occasion to save nonrenewable energies and to save money. The planned use of natural light has become an important strategy to improve energy efficiency. The amount of energy demand generated by the use of electric lights is considerable and gives the possibility of significant savings by daylighting. An additional saving that is associated with natural lighting; a reduction in cooling loads for air-conditioned buildings. Despite our country lies among Sunbelt area; it happens wherever you go: It’s a bright sunny day, and the electric lights are on in office buildings, schools, stores, and most non-residential buildings, there’s plenty of natural daylight outside, free for the taking, but the most frequent choice is to use electric lights. Lighting alone consumes 34 % of total electrical lighting energy and 25 % of total energy sold in Egypt. Green lighting technology is a term coined by the researcher; it is just a technology that uses the potential of modern sciences and technologies according to the value of environment, it means using daylighting technologies that wholly depend on renewable energy such as the solar one. Windows alone do not provide satisfactory daylighting for deep spaces due to poor penetration in the space. So that; this PhD thesis proposes green lighting technologies that depend in the first place on sunlight and its features (direct, diffuse and reflected).That is basing on the idea of channeling daylight into buildings in tubes likewise water, electricity, and gas; concerning: sun tracking systems, solar collectors, heliostats, light pipes and optical fibers. The study aims to construct a designing tool to support designers to incorporate the offered Green Daylighting Technologies into their buildings to reduce lighting loads and subsequently reducing HVAC loads.