Abstract: In order to further study the energy saving and efficiency improvement of refrigeration systems, the progress of research on waste heat recovery in refrigerator refrigeration systems in recent years was investigated. The economic feasibility and feasibility of different waste heat recovery methods for refrigerator waste heat recovery were comprehensively analyzed. The feasibility of using semiconductor thermoelectric power generation (TEG) technology for waste heat power generation was specifically studied. Through system design, theoretical calculation, and experimental verification, it was found that waste heat recovery can be achieved by using semiconductor waste heat power generation. The experimental results showed that the target maximum power generation of 1.51 W can be achieved under the Pull Down (PD) condition; and the outlet temperature of the condenser can be effectively reduced to within 45 ℃, with a decrease of 36 ℃~39 ℃ under the PD mode and a decrease of 18 ℃~19 ℃ under the energy consumption mode, which improves the system subcooling degree. However, due to the modification of the prototype, there is an increase in thermal load, resulting in an overall improvement in energy efficiency. Under PD mode, the power increased by 5.6%~17%, and under energy consumption mode, the power increased by 13%~19%. TEG technology, as a waste heat recovery technology with great potential, was explored through experimental research on its feasibility coupled with refrigerator refrigeration systems. With the rapid development of thermoelectric power generation materials and related technologies, continuous research is needed on system design matching, heat exchanger-power generation module heat transfer optimization, and electricity storage and conversion, which has important reference significance for achieving energy-saving and efficiency-improvement of waste heat recovery in refrigerators or other refrigeration systems.

Key words: Waste heat recovery, Refrigerant system, Low-grade waste heat, Thermoelectric power generation