There are two main refrigeration principles for car refrigerators: semiconductor refrigeration and compressor refrigeration.
Principle of semiconductor refrigeration
Semiconductor refrigeration is achieved through the "Peltier effect". When current passes through a special semiconductor material, one side absorbs heat and becomes cold, while the other side releases heat and becomes hot. Car refrigerators use this feature to use the heat-absorbing side for cooling and the heat-releasing side for heat dissipation through fans. The advantages of this technology are simple structure, no compressor, small size, light weight, and almost no noise. The disadvantage is that the refrigeration effect is limited, and the lowest temperature can only reach about 15°C below the ambient temperature. It is suitable for short-distance use or storage of drinks and fruits that do not require extremely low temperatures.
Principle of compressor refrigeration
Compressor refrigeration is similar to the principle of household refrigerators. The refrigerant is compressed into a high-temperature and high-pressure gas through a compressor, and becomes a liquid after heat dissipation through a condenser. Then it becomes a low-temperature and low-pressure gas through throttling and pressure reduction, and finally absorbs heat in the evaporator to achieve the refrigeration effect. This car refrigerator has a strong refrigeration effect, and the temperature can drop to -18°C or even lower, which is suitable for storing ice cream or food that needs to be stored at low temperatures. The disadvantages are that the structure is complex, the compressor makes slight noise when working, and the refrigerator is heavier.
