Solar cell

week no: week 7 (1/3/2012)

objective:

• Solar cell diagram
• Photovoltaic characteristic

Content:

The figure above show the solar panel which cell connected in series and parallel

A solar cell is a solid state device that converts the energy of sunlight directly into electricity by the photovoltaic effect. Assemblies of cells are used to make Photovoltaic module, also known as solar panel. When the solar panel is connected in series the voltage output will increase, while the solar panel connected in parallel the current output will increase. The solar panel connected in series to provide PV panel string, while for PV array is the combination of several PV panel string in parallel connection.

 

There are two types of PV cell

        i.            Crystalline cells

a.       Monocrystalline ( Single crystalline)

b.      Polycrystalline ( multi crystalline)

      ii.            Thin layer (film) cells

The amount of solar power available per unit area is knows as irradiance. As the irradiance varies there is almost linear variation of the short circuit current. The open circuit voltage however does not change dramatically, it increase slightly as shown in figure below. The graph assumes that the cell temperature is constant, unaffected by the differing irradiance. It is because the voltage remains reasonably constant under varying irradiance solar cell are well suited for use as battery charger.