6 Solar Energy Absorbers Himanshu Dehra Noise Behaviour Institute, McGill University Department of Public Health Medicine, McGill University Energy Management Research Centre, McGill University Department of Mining Engineering, McGill University Department of Building Engineering, Concordia University Centre for Building Studies, Concordia University Concordia Institute of Information Systems Engineering, Concordia University Département de Communication Sociale et Publique, UQÀM Akal Takht (1-140 Avenue Windsor, Lachine, Québec) Concordia 1. Introduction The most of the solar energy is absorbed by moving planets, their satellites and their surrounding environment viz., planet surface, planet atmosphere, forests, farms, rivers, ponds, lakes & seas, living beings and civil structures (e.g. buildings, green houses, thermal power plants, collectors, panels, roads, bridges, ports, canals). The life and its activities are reliant upon the sun’s radiant energy which apart from the earth is also stocked up by green plants. In addition to the primary role of light in living economy, a continual environment of mixed radiations from various sources of radiations produce other effects, reactions and adaptations, which have susceptibility to influence the life activities of the living organisms living in a continual environment. The solar radiation is passed through the earth’s atmosphere and while passing, the solar radiation is reflected, scattered, and absorbed by gas molecules, ozone, water vapour, clouds and dust. The length of atmospheric path travel by sun rays is determined by the air mass m, the ratio of the mass of atmosphere in the actual earth-sun path to the mass which would exist if the sun were directly overhead at sea level (m=1.0). The sunlight is the major source of radiations on the earth. The spectrum of sunlight includes ultraviolet radiation, visible light, infrared rays and radio waves. The x-rays are generated by solar flares and their ionization due to absorption occurs high in the earth’s atmosphere. X-rays also reach the earth’s atmosphere from various celestial sources. About 60 per cent of the energy of sunlight is in the invisible infrared region’s indefinite limit in radiation spectrum of sunlight. The sunlight radiations of shorter wavelengths are absorbed in the earth’s atmosphere before such radiations reach the surface of earth. The ozone layer is formed high above the atmosphere through absorption of ultraviolet radiation by oxygen. The reversible reaction, again turn the ozone to absorbs longer ultraviolet rays, re-forming oxygen. The radioactive emanations consist of three components: i) gamma rays, which are penetrating radiations of very short wavelength but otherwise like x-rays; ii) alpha particles, www.intechopen.com