There are two main types of refrigeration:  vapor-compressor and thermoelectric.  Vapor-compressor refrigeration is the most common and consists of a compressor and a circulating fluid while the thermoelectric system is composed of two semiconductors and a fan, a process known as the Peltier effect.  But what is it and are there advantages of a thermoelectric wine fridge versus a traditional wine bottle cooler? 

While students of physics are introduced to Jean Charles Athanase Peltier as a physicist, he was actually a 30 year old Frenchman who retired from his clock making business and began curiously investigating electricity.  He joined a copper wire to a bismuth wire and then connected a battery to each end.  [It is very possible that he just happened to have those two pieces of wire on hand and gave little thought that they were different metals.]  When the electricity flowed he discovered that one side of the joint between the copper and bismuth wires was hot, while the other side was cold.  

He had inadvertently discovered the thermoelectric heat pump.  The Peltier Effect, as this discovery is known, shows that electricity can cause a heat differential at the junction of
two different metals joined together. 

While this technology can actually be used as a temperature controller to either heat or cool, in practice the main application is to cool – as in a thermoelectric wine fridge by simply adding a fan to force the heat from the cabinet of the wine bottle cooler.

There are a number of advantages of this technology.  Because of the very nature of the science, the thermoelectric heat pump can be very small and of a flexible shape.   So, a thermoelectric wine fridge can be very small and fit into small spaces (from a 1-2 bottle wine bottle cooler to 28 bottle wine bottle refrigerators).  They are also eco friendly since they use no CFCs or HCFC's (the abbreviations for chlorofluorocarbons) which are known to be partially responsible for the thinning of the ozone layer.  In addition, since due to the
design the only moving part in a thermoelectric wine fridge is a fan to move heat away from the cooling cabinet, the unit is known for its silent operation.  And since there is only one
moving part, there are generally fewer maintenance problems in this type of wine bottle cooler.  And especially important for protecting wine quality, there is only a temperature variation of ± 1-2°C from top to bottom of the thermoelectric wine fridge (compressor units can vary as much as ± 5°C).

Unfortunately, some of the advantages also become disadvantages.  Because of the limitations of the science, a thermoelectric wine fridge is only available in small capacity units.  And to maintain maximum economic benefit (through reduced electricity usage) the ambient room temperature where the wine bottle cooler is located can only be a maximum of 77°F or -25°C.  In addition, the difference between the ambient temperature of the room and the temperature setting in the wine bottle cooler cabinet can only be 13°. Lastly, these wine bottle refrigerators cost a little more than a comparably sized vapor-compressor model.

As shown, a thermoelectric wine fridge has advantages and disadvantages.  All the major
manufacturers of wine bottle refrigerators have at least a small line of thermoelectric models.  Do your research, check the warranties and compare the cost and size with comparable units.  If you need a small capacity wine bottle cooler and a desire to be environmentally conscious, a thermoelectric wine fridge is a good choice for you.