Residential refrigeration is one of the largest contributors to home appliance energy consumption in the U.S. This energy use is nearly doubled if commercial refrigeration is included. By using cold outside temperatures for cooling, however, energy savings can be realized. In this work, a thermosyphon-assisted cooling system for a household refrigerator is presented. A single finned copper-tube thermosyphon with methanol as the working fluid is used. An environmental chamber that can reproduce outside ambient temperatures to −5 °C is located above the refrigerator. Results are presented for different outside temperatures, fan speeds, and filling ratios in the thermosyphon. The electricity use for both the original equipment refrigeration and the thermosyphon system is reported. The interior temperature is found to vary depending on the number of fans that are used to blow air over the thermosyphon evaporator in the refrigerated space. This can be used to produce localized micro-climates within the refrigerated space for further energy savings.
He, T., Mei, C., & Longtin, J. P. (2017). Thermosyphon-assisted cooling system for refrigeration applications. International Journal of Refrigeration, 74, 165–176. https://doi.org/10.1016/j.ijrefrig.2016.10.012