Photovoltaic solar energy is electric power at no energy cost

What is photovoltaic solar energy?

In one sentence: photovoltaic solar energy means converting solar light directly to electric power. The photovoltaic or photoelectric effect is the separation of elementary electric loads (plus - minus) in a semiconductor boundary layer by incoming light.

In european history the photovoltaic or photoelectric effect was watched for the first time in 1839 by french physicist Alexandre Edmond Becquerel, though an earlier discovery is possible, may be in China or India. The word photovoltaic is made from the greek word photos (light) and the name Volta, from Alessandro Volta, a pioneer of electrotechnics from Italy.

The technical exploitation of the photoelectric effect and the introduction to common technical knowledge came in 1958 with the first electric power supply for space satellites entirely by solar cells. Today solar electric power generation is used all over the world both for private homes and public supply.
Picture: Silicon solar cell for electric power generation

What is a photovoltaic solar cell in detail?

The basic technical unit for solar power generation is a solar cell. It holds two layers of a highly purified chemical element, most commonly silicon (chemical symbol Si). Silicon is after iron (latin: ferrum, symbol Fe) the most frequent chemical element in the earths crust. It exists in huge quantities in simple sand like deserts and beaches all over the world. All microchips, computer processors, computer memory and others are made from silicon.

The production of silicon is similar to the melting process of glass. It is very environmentally friendly in particular if the processing energy is made from solar energy. At the end of their life span of at least 25 years solar cells can be recycled at almost 100 per cent.

What makes sleeping sand a solar electric power generator?

Initially the sand is molten. In the liquid phase the silicon is separated as pure as possible. Now we see highly purified silicon which is not at all able to conduct electric current. What makes non conducting silicon an electric power generator? The trick is called donation.

One part of the silicon is donated very small quantities of the best working chemical element to form a p-conductor (conducts positive electrical loads), the other part is donated to form an n-conductor, which conducts positive electrical loads.

Now we have two semi conductors which are then baked together as very thin layers and form another layer called boundary layer. This is the place where it happens. Incoming light makes the boundary layer separate n-loads from p-loads and this is our basic solar energy photoelectric power element. Certain numbers of photoelectric cells are assembled mechanically and electrically to solar panels.

Photovoltaic solar panels

contain a number of photovoltaic cells electrically connected and mechanically protected for all known weather conditions and easy assembly to plants of various power classes. There is a number of different types of solar panels, most common types are 12 or 24 Volts DC, 120 or 170 to 200 Watts.