Function

• Portable coolers use energy from semiconductors, as opposed to air compression systems in regular refrigerators. The cooler can typically use an alternating current (AC) power adapter like home electronics devices or a 12 volt direct current (DC) adapter that plugs into a vehicle's cigarette lighter. Inside the casing, the machine uses gas pressure to cycle a fan which moves air in and out. Propelled by electricity and pressure, the air moves across a device called a heat exchanger. The exchanger is made out of metal alloy and moves heat energy either into the food compartment or out of it.
  
  

Uses

• The calibration of the cooler makes it cool the inside by a certain number of degrees, often making the air 25 degrees Fahrenheit to 30 degrees Fahrenheit colder than the external temperature. Many models can also heat the inside by a similar amount or up to a certain maximum to avoid overheating.
  
  

Types

• Different models of portable coolers are distinguished by the volume in liters of their storage area and by available features such as wheels or wine bottle shelving.