" Read out the operating voltage of the TEC Controller.
Note: If you are working with a system, note the operating voltage of it.
Calculate the power consumption of the Peltier element (PPe = UAp * IAp).
Add the power consumption of the Peltier element to the power consumption of the TEC controller (rule of thumb: PTot = power consumption of the Peltier element * 1.2).
Check: PTot <= POut power supply
With the values from 3. you can find appropriate power supplies at your electronics dealer