They're essentially using Peltier elements to cool the elements electronically. They're also using two elements stacked in series for a lower total temp. Thank

They're essentially using Peltier elements to cool the elements electronically. They're also using two elements stacked in series for a lower total temp. Thank god the CCD is small -- a Peltier unit, as a heat pump, is pretty inefficient, topping out a ~15%, at a low t delta. When you stack two on top of each other, the efficiency is now 2.25%, and this only gets worse as the delta increases or more units are added.