All energy from the sun that reaches Earth arrives as solar radiation, part of a large collection of energy called the electromagnetic radiation spectrum. Solar radiation includes visible light, ultraviolet light, infrared light, radio waves, X-rays, and gamma rays. Radiation is a way of transferring heat. This is called diffuse solar radiation.
Solar radiation that reaches the Earth's surface without diffusing is called direct beam solar radiation. The sum of direct and diffuse solar radiation is called global solar radiation. Atmospheric conditions can reduce direct beam radiation by 10% on clear, dry days and by 100% on cloudy and dense days. Photovoltaics is a form of active solar technology that was discovered in 1839 by 19-year-old French physicist Alexandre-Edmond Becquerel.
Energy from solar plants may be available in the future for 2.2 US cents (1.23 rupees), compared to grid power at 9 cents US dollar (Rs. The two most economically and technically feasible solar energy options are the viable option for a sustainable future energy mix. Agua CalienteThe Agua Caliente Solar Project, in Yuma, Arizona, is the largest photovoltaic array in the world. PhotosynthesisAlmost all life on Earth depends on solar energy as food, either directly or indirectly.
For the energy budget at the Earth's surface to be balanced, surface processes must transfer and transform 47 percent of the incoming solar energy that the ocean and land surfaces absorbed back into the atmosphere and eventually into space. Thermal mass systems use paraffin wax or various forms of salt to store energy in the form of heat. Solar technologies are widely characterized as passive solar or solar active, depending on how they capture, convert and distribute solar energy. The intensive research efforts of energy scientists regarding solar options have helped to improve the efficiency of photovoltaic technology, which made it possible to increase the speed of solar photovoltaic deployment for the industrial electricity generation scale.
Once the solar technology equipment is built and commissioned, solar energy does not need fuel to operate. However, the technical feasibility and economic operation of these technologies in a specific location depend on the available solar resource. In other words, about 30 percent of incoming solar radiation is reflected in space and 70 percent is absorbed. The photovoltaic effect has been known since 1839 and, despite extensive research efforts since then, solar energy is still very expensive.
The energy that reaches Earth is measured as solar irradiance (energy per second in one square meter).
