Increasing energy efficiency of refrigerators by using thermal energy storage in phase change materials

Thermal energy storage systems enable utilization of renewable energy resources and waste heat by storing energy produced when these resources are available. Thermal energy storage in phase change materials (PCM) is used to increase energy efficiency in heating and cooling applications. Improving energy efficiency of refrigerators by using thermal energy storage in phase change materials, the objectives of this project are: Optimization of on-off durations in refrigerators, decreasing energy consumption of the refrigerator by increased system performance with the effect of PCM, increasing frozen food quality by decreasing temperature swings,protecting food for a longer period in case of a power cut. Genarally there are two compartments depending on their purpose of usage in the refrigerators; one working at a temperature interval of (-18)-(-25) °C, and the other at (+2)-(+8) °C. PCMs were prepared suitable for refrigerator temperature range. Thermal properties of these PCMs were determined and thermal energy storage (TED) experiments were performed in the refrigerator. Corrosion tests have been carried out for metallic sample container–PCMs pair, and the most compatible metal-solution pairs were chosen. Applications of the PCMs in refrigerator 9,4% energy saving have been provided. Compressor life is extended by increasing time of off durations of compressor,comparing in a 2,6°C difference in the temperature inside the cabin during the power cut. Finally, the economic and environmental benefits to be achieved by using PCM in refrigerators have been calculated.