[gravata]Models that use more efficient and resistant compressors.[/gravata] By Fernando Borba, Refrigeration Technical Specialist.There are several water cooler models in the market, which are classified as “electronic”. The use of this term gives the impression that it’s modern equipment and with advantageous features for users. But what happens is just the opposite. The so-called “electronic water coolers” use Peltier type thermoelectric wafers instead of a compressor. These wafers are capable of cooling but are more suitable for devices in which the need for refrigeration is very small, such as microprocessors. In water coolers, using these wafers is not a solution that enables the same performance as traditional equipment, like the compressor. The first aspect to consider is that water coolers with compressors consume much less electricity. A rigorous assessment made by the Proteste Institute in September 2010, with six models of electronic water coolers showed that all had very high energy consumption level, besides having weak performance in chilling water. The fact is that the cooling process based on vapor compression provides much higher performance for this application. That is, with a compressor, the cooler makes water colder and cools it faster. The compressor’s robustness and resistance to grid voltage fluctuations are other factors that must be considered in comparison. To complete, compressors present another important advantage with regard to the water cooler design: with them, it’s not necessary to include components such as micro-fan, supply source, transformer, and electronic board, parts that are obligatory in any system based on the Peltier process. Even regarding health aspects, models with a compressor have an advantage since there’s no possibility that they can contaminate the water. The same cannot be said of thermoelectric wafers which, in some cases, are enclosed within the water reservoir in order to gain space.