A while back, I purchased a 38W peltier cell on ebay. It wasn't powerful enough, so I'm looking at something along the lines of a 92W. I noticed, however that my 38W and the 92W have the same dimensions and the same number of junctions. Also, dT of the 92W is only 1 degree C above the 38W. How is this possible? Are the sellers providing false information? Is one made out of a material with a higher Seebeck coefficient? If so, will one be more efficient than the other? Also, a general explanation as to how the different factors effect a cell would be greatly appreciated.