The type of transformers that take an active role in the transmission and distribution systems of electrical energy is distribution transformers which have a large number of uses in the industrial field. These transformers are cooled by different cooling systems according to the places in which they are used, and they are named oil-type and dry-type transformers according to this cooling type. In the cooling of oil-type transformers, naphtanic and paraffinic oils, namely paraffin (wax)-containing insulating materials with high dielectric strength, called classical transformer oil, are used. Innovative approaches aiming to increase the combustion degree and dielectric strength of these oils have been increasing in recent years. In these studies, ester-based oils with better properties than naphtanic or paraffinic transformer oils developed with innovative approaches were used instead of conventional transformer oils, resulting in increased performance and useful life of transformers. However, regardless of the characteristics of transformer oils, their features such as burning-explosive properties that cause environmental pollution and excess maintenance-repair costs create disadvantages in their use in transformer insulation. In this study conducted to eliminate such disadvantages, the oil-type transformers are cooled by using thermoelectric coolers, which are environmentally friendly and renewable energy sources. As a result of the study, it was determined that the thermoelectric cooling system provided 15-20% better cooling than naphtanic and ester based oil cooling types. It is considered that this will take place as a new technology and type in distribution transformer cooling systems.