Powering of Peltier Elements and power issues!
I have done experiments before, peltier does not sink more than 2A of current. Why so?


Imax is a never exceed specification.  If you exceed that you might break the device.  



Based on this chart if your hot side is heatsinked well enough to keep it below 50C you would expect it to draw a little more than 4.5A at start up when the delta T is 0. That is when the hot side and cold side are the same temperature.  So your power supply shouldn't run in to current capacity issues.  

Depending on what you're trying to do you might want to run them at a lower voltage than that.  All the power that you put in to a peltier becomes heat.  So while higher voltages can potentially move more heat from one side to another it doesn't necessarily result in lower cold side temperature.  When I experimented with peltiers I stacked two on top of each other and found they got colder when powered in series from a 12V power supply than when they were in parallel.