Peltier Cooling: Heat Transfer & Electron Theory

[cragar]

When the heat gets transferred to one side and the other side gets cold , what causes this cooling effect , why does the heat go from one side to the other on the different metals ,
does this have something to do with the electrons.

 

[russ_watters]

http://en.wikipedia.org/wiki/Thermoelectric_effect

 

[cragar]

I read that before I posted this , what doesn't make sense to me is that why does one get hot and one get cold , why don’t they both get hot , just one hotter than the other.