What is a solar cell?
A Solar cell is a semi-conductor device which directly converts sunlight into electricity. Solar cell converts sunlight into electricity by photo-voltaic effect. Hence, they are also called photo-voltaic cells.
A typical commercial silicon solar cell is shown in the figure.
The solar cell generates current and voltage at its terminals when sunlight falls on it. The amount of electricity generated by solar cell depends on the amount of sunlight incident on it.
The electricity generated by solar cell depends upon the intensity of light, the area of a cell and and the angle at which light falls on it.
The higher is the intensity of sunlight, the more is the electricity generated by the solar cell. If a area of a solar cell is increased, the current generated by solar cell is increased.
The power generated by the solar cell is optimum when sunlight falling is perpendicular to the front side of solar cell.
A solar cell is a two terminal power generating device, one is a positive terminal and another is a negative terminal.
Also read : How does a Solar cell generates Electricity?
In common, all solar cells, irrespective of the technology and material used have only two terminals ( positive and negative terminal) as output.
Typically solar cells have front contact at the top, emitter base junction or n-p junctions in the middle and the back contact at the bottom.
At the emitter-base junction, the separation of negative and positive charge takes place.
Electricity is supplied to a load by connecting its terminals to the front and back contacts of a solar cell or solar module or solar panel is shown in the picture below.