Peltier POWER rating question!!!

[Mode]

How can I know if the Peltier I'm having is really the 72W(rated) peltier or not?
Is there anyway to find out the real wattage of a peltier?

sorry, this is the same post i have posted on the General discussion but i guess, it's better be in the cooling section.

[TT120]

If you multiply the current it's drawing by the voltage it's running at you will get the watts. IE: 9 amps X 12 volts = 108 watts

[Badger]

TT120 (Apr 27, 2001 02:26 p.m.):
If you multiply the current it's drawing by the voltage it's running at you will get the watts. IE: 9 amps X 12 volts = 108 watts

Hmm,
I'm afraid thats not really true. The rating of a peltier (or Qmax) is the maximum heat energy it will transfer at a delta T (differential temp) of zero.
The power it consumes (Vmax x Imax) is much higher, usually about twice as much.
This is the spec of a typical 72w peltier:

Imax 8.5A
Qmax 72W
Vmax 14.4
DTmax 69C

As you see to achieve a Qmax of 72W it consumes 8.5A at 14.4V (122W)