Yes, pretty inefficient indeed but the neat thing (in a Science Fair sort of way) about the Peltier device is it chills or heats (if you reverse the polarity) with just voltage & current. In the 1980s these were being experimentally used in fireman's suits and astronaut's suits to try and reduce body temperature.
I think the 115 number in Jason's post referred his 115 amp alternator and not 115V. Everything I've read about this compressor (from people who have posted comments about everything from old cars to RVs to all sorts of things) tells me unless you have a vehicle the size of a Mazda Miata you're going to need 12V and 60 amps to run the motor at 4000 rpm. A good number of people have said theirs had to run constantly at the fastest speed to cool something that would compare in size to maybe a Chevy Nova or a Honda Accord and it didn't keep it cold...just cool. But I don't know where these people were living. Yesterday we had an unexpected cool morning (for August). When I went to the post office it was only 81 F degrees and I could tell the compressor was cycling on/off. Later when the temp got up to 95 F it was running constantly. I saw one post where a person tried one of these in an airplane but learned they must be kept level or they have failure issues.
