Photovoltaics
The history of “Photovoltaic”
In the late 19th century, solar electricity discovered by German physicist named Alexandre Edmond Becquerel accident where the sun rays fall on the solution of electro-chemical research materials, so the charge of electrons in the solution increases, there is no scientific explanation of the event. Not until the early 20th century, Albert Einstein called the discovery of this natural electrical event with “Photoelectric Effect”, which is the basic understanding of the “Photovoltaic Effect” (Albert Einstein got the Nobel Prize in Physics). 
“Photoelectric Effect” comes from Einstein’s observations on a plate of metal release “photon” particles of light energy when exposed to sunlight. Photon continuously urged metal atoms and form a particle “Photon Energy”-is the wave of light energy.
Ultraviolet light waves, light that are high charged photon energy and short wavelength, while red light (infra-red) is low charged photon energy and long waves.
Then around the year 1930, research continued and related to discovery of the “Quantum Mechanics” concept, to create new technologies “solid-state”, which then the Bell Telephone Research Laboratories company create the first solid Solar Cell.
Year 1950 – 1960, technology of solar cell design and efficiency continued and applied to the spacecraft (photovoltaic energies). In 1970′s, the world encourage “renewable” alternative energy sources and environmentally friendly, then the PV is applied to the “low power warning systems” and “offshore buoys” (but the PV production could not be much because it is still “handmade”).
Just in 1980, the PV companies joined with government energy agencies in order to produce the PV cells in large numbers, so the price of solar cells can be more suppressed as low as possible.
