Solar Energy: A New Trend in Alternative Energy Technology
Electricity has become an integral part of the present society. It has fueled the technological revolution which has eventually led to the development of the society. But as our society develops, our dependence on electricity continues to grow. The world demand for energy is projected to about triple of the present energy consumption by the end of this century due to the current trend in population and economic growth. So as our demand for electricity grows, we feel the need for some alternative sources of energy as the present requirement of electricity completely relies on fossil fuels which are limited and also produces gaseous waste pernicious to global health. To combat these problems, many alternatives are available, among which solar energy is one such technology.
The world at present consumes energy at the rate of approximately of 13 terawatts(TW) per year which is much less than the solar energy reaching the earth per hour. So improving the existing energy networks will not be adequate enough to supply the global requirement of energy in a sustainable way. Also the supply and demand of energy determine the extent of global development as the sufficient supply of energy is linked to global stability and economic growth. So exploiting solar energy as a clean and abundant energy is the goal of the technological advancements of the present century.
Solar energy is an important form of renewable energy that produces energy harnessing the radiant form of energy obtained from the sun and this is also the most readily available source of energy. The routes for exploiting solar energy depends mainly on the fundamental steps of capture, conversion and storage. It is also a non-conventional source of energy as it is non-polluting and thus helps in lessening greenhouse effect. The sun radiates more energy in one day than that the world uses in one year. The sun produces this energy through a process known as nuclear fusion in its inner core. Only a small fraction of the solar energy that the sun emits into the space is available for our earth and this much of energy is more than sufficient to fulfill.
Solar energy can be used to produce electricity. Two such ways are photovoltaics and solar thermal systems. Solar cells are made up of silicon which is the second most available substance on the earth. The trend in converting solar energy to electricity via photovoltaic solar cells is dramatically reducing the cost/watt of delivered solar electricity-by approximately a factor of 5-10 to compete with fossil and nuclear electricity and by a factor of 25–50 to compete with primary fossil energy.
Electricity is produced when the solar radiation is directly incident on the solar cells causing the electrons to move around. The motion of the electrons constitute an electric current.
Through solar photovoltaics, solar radiation gets converted into dc electricity directly which can be used as it is or can be stored for future use.
Compared to other sources of energy, the photovoltaic systems are much more expensive and requires a large number of solar panels. Solar energy is usually used in remote areas for power generation that are far away from electric power lines. In recent years, technological development has led to the fabrication of single-crystal solar cells exploiting the concepts of thin films, organic semiconductors, dye sensitization and quantum dots which offers opportunities for cheaper and more efficient solar cells. Thus the solar cell implementation and latest innovations in semiconductor technology can revolutionize the way in which solar cells are conceived in the coming years.
Like solar cells, solar thermal systems use solar energy to produce electricity, though in a different way. This technology is to identify cost-effective methods of converting solar energy into storable and dispatchable thermal energy. Solar thermal system generally uses a solar collector with a mirrored surface to focus the incident solar energy into a receiver that heats a liquid. The super-heated liquid is then used to make steam that eventually produces electricity.
Thus the solar technology provides us with a renewable source of energy that is available in ample, and can be harnessed using the latest innovations in semiconductor technology to satisfy the growing demand of energy and this is going to revolutionize the energy generation in the coming years.