Sustainable Technologies for Cutting down Energy Requirements for Lighting and Air Conditioning in Buildings

In the current scenario of increasing population and rapid urbanization, energy requirements in human habitats are exponentially increasing which is nearly 40% of the total energy produced. Therefore technologies and methods for reducing energy utilization in buildings are being developed throughout the world. Energy efficiency and conservation are two important aspects as it takes a larger stack in running the buildings, which is being highlighted in the „Green Building‟ concept. In urban buildings, energy is required mostly for lighting and air conditioning. In terms of lighting, daylighting and less energy intensive lighting devices like LED, CFL etc. are being used. Use of renewables like solar energy for power generation and also for air conditioning were also found to be used in buildings. Recent researches are based on using the building itself or its parts like roofs, facades, windows etc. for utilizing solar powers using technologies like Building Integrated Photovoltaics (BIPV) and Building Integrated Solar Thermal (BIST). Similarly building integrated thermal energy storage using phase change materials along with construction materials for space cooling and heating were also been used. This paper highlights such sustainable technologies which are used to reduce the energy requirements for lighting and air conditioning in buildings.