Phase change material-enhanced solid-state thermoelectric cooling technology for food refrigeration and storage applications

Abstract

In this work, a phase change material (PCM) enhanced thermoelectric (TE) Peltier module-based cooler has been proposed for the refrigeration and storage applications of the food industry. The proposed prototype used an organic PCM (product: RT 2HC; supplier: Rubitherm) with a melting temperature of 2 °C to provide passive cooling to maintain the temperature below 4 °C which is the typically recommended temperature for storage and transportation of perishable food items. The PCM will melt during the cooling of the food item. This allows for managing the energy demand, i.e., PCM will be discharged when it is needed for the system requirement. A detailed description of the manufacturing process of the prototype is presented. In the current study, different food items were tested in the manufactured prototype for cooling as well as to keep the temperature below 4 °C. Cost analysis and relative uncertainty calculation of the proposed prototype were performed. Mathematical modeling has been presented to calculate the amount of PCM required for the prototype. A comparative study was conducted between the commercially available cooler and the proposed system where the proposed system outperformed at maximum and minimum energy input. The proposed cooling system maintains a temperature below 4 °C for an infinite time at 11.4 W power input (6 V and 1.9A) and 26 h at a minimum power input of 4 W (3.1 V and 1.3A) in the ambient temperature of nearly 21 °C. The developed cooler could hold the temperature below 4 °C for nearly 7 h without any energy input. Moreover, the developed prototype has a COP of 0.75 at a temperature difference of 19 °C and a power input of 11.4 W. Furthermore, the life cycle assessment of the proposed system was conducted based on ISO 14040:2006(E) and it is found that the system emits 1170 kg CO2 and 1.04E-06 kg CFC-11 during 15 years of its lifetime.