When solar radiation falls on solar cells, it is converted directly into DC electricity due to the photovoltaic effect.
90% of the current commercial production of solar cells are made of single-crystal and multi-crystalline silicon wafers.
There are multiple applications of PV technology: space satellites, remote radio communication booster stations, marine warning lights, lighting, solar-powered vehicles, etc.
Silicon, an intrinsic semiconductor can be converted into an extrinsic semiconductor by doping.
Silicon is doped with other elements to create n-type and p-type semiconductors. n-type silicon has excess electrons while p-type silicon has excess holes.
Electron transfer occurs at the p-n junction, resulting in a current generation.
The 3rd generation of solar cells are multi-junction cells for higher conversion efficiency.
For an efficient cell, it is desirable to have high values of fill factor, short-circuit current and open-ciruit voltage.
The most common PV modules have series connection of 36 silicon cells to make it capable of charging a 12V storage battery.
The challenges of PV modules are cell mismatch and shading.