HOW SOLAR PANEL WORKS ?

Solar panel is a device which convert's light energy in to electrical energy .

it is basically a PN junction diode having some important change in its construction . it works on photoelectric principle.

CONSTRUCTION - 

To constructing a practical solar panel we will arrange a PN junction and at the contact surface positive charge carrier's (holes) will move toward N-type semiconductor and negative charge carrier's (electron's) will move toward P - type semiconductor  (opposite charge attracts each other) forming depletion layer .

 

A thin layer of either of one kind of semiconductor  is used towards the light rays so they can reach to the depletion layer easily ,because there neutral charge carriers atom's will absorb energy from photon's containing by light rays to produce charge carriers .  

 

That charge carrier's than get influenced by already present electrostatic field created due to depletion layer whose direction is from  "+ to - " due to this electric field there will be force on charge according to the .

                                       E = F/q

                                       F=Eq

And that force will make - ve charge carriers to enter N-type region and + ve charge carrier will enter into P-type semiconductor , but although we generated free charge's they will not move in semiconductor because they don't have such high conductivity as conductor's .

So we provide metal strip to N-type semiconductor than there will be accumulation of charge and if we connect it to other end P-type semiconductor  + charge carrier's will accumulate there .

So as charge increases voltage will increases so current will start to flow  .