Born in Paris, Edmond Becquerel (1820-1891), a French physicist in 1839, is known for his studies in the solar spectrum, magnetism, electricity and optics. He is best known for his discovery and unraveling the key principle to solar energy cells, the photovoltaic effect. He received his doctorate from the University of Paris, and eventually took a professorial position at the Agronomic Institute of Versailles. He was especially interested in phosphorescence and luminescence, chemical reactions caused by exposing certain substances to light. In the1840s he found that these reactions could produce an electric current in both liquids and metals. The connection between light energy and chemical energy was seized upon by many scientists in the following years, and research has led to the development of the photoelectric cell.
The photovoltaic effect is the basic physical process through which a photovoltaic cell converts sunlight into electricity. Sunlight is composed of photons which are packets of solar energy. These photons contain different amounts of energy that correspond to the different wavelengths of the solar spectrum. When photons strike a photovoltaic cell, they may be reflected or absorbed, or they may pass right through. The absorbed photons generate electricity.