Thermo-electric coolers operate according to the Peltier effect. The effect creates a temperature difference by transferring heat between two electrical junctions. A voltage is applied across joined conductors to create an electric current. Heat is then deposited at the other junction and will only cool to around 13 degrees below ambient. This product is designed to keep things chilled regardless of the ambient temperature.
Compressor-driven refrigerators (like the TOTALFREEZE range) use vapor-compression, where an electrically powered compressor increases the pressure on the gas, and then condenses the hot high pressure gas back to a liquid. Our TOTALFREEZE range will freeze down to –20°C regardless of the ambient temperature.