Technical Note – Bypass Diode Effects in Shaded Conditions

Bypass diodes are a standard addition to any crystalline PV module. The bypass diodes’ function 
is to eliminate the hot-spot phenomena which can damage PV cells and even cause fire if the 
light hitting the surface of the PV cells in a module is not uniform. The bypass diodes are usually 
placed on sub-strings of the PV module, one diode per up to 20 PV cells. This configuration 
eliminates the creation of hot-spots and enables the PV modules to operate with high reliability 
throughout their lifetime.
In addition to effectively fulfilling this function, many people believe the bypass diodes are also 
effective in reducing power loss due to shading in PV installations. This is far from the truth. In 
this document we will analyze several everyday scenarios and show ...


Read it all in this very good pdf