A few notes on Thermoelectric coolers pros cons and others.

A TE cooler works on the Peltier Junction Effect to transfer heat across 
a semiconductor junction.  It uses WADS of current to do this.  (But you knew
that)  The commercial TEs you buy from Koolmate/Igloo will hold the contents
at 40F below ambient (IF YOU DON'T OPEN THE LID)  They work fine while your 
alternator is converting dinos to watts but will suck your battery as dry as
a desert drunk if you make the mistake of leaving it on with the motor off
for any significant period of time.  Sooo they're kinda a good idea but don't
work well in hot summer weather.  You can provide better cooling if you force
feed air through the exhaust vanes and insulate the box with your sleeping
bag.  Of course they're water proof and can function as a conventional "ice
box".  YMMV of course but I sold mine long ago.
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         ___  / __   __/   ____/         Al Knoll HP Performance Technology /
        /    /      /     /             Center    Roseville, CA, USA 95747 /
       _____/      /     /             916.785.5317    (Telnet 785-5317)  /
      /           /     /             email:  alf@hpptc44.rose.hp.com    /
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