Phase Change Materials (PCM) for a Zero-carbon Food Preservation Technology in Remote Areas

Abstract Phase Change Materials (PCM) are thermal storage materials that are capable of storing renewable energy and improve the performance of a solar cooling system. Since solar power is not consistent everywhere and the operating conditions of cooling systems are varying, a specific study is needed to implement this principle for a particular location. This research work aims at developing small-scale solar domestic refrigerator and freezer systems to work with PCMs and solar energy. The software, System Advisor Model is used to select the PV system for the location. An experimental setup of a 210-litre refrigerator and a 250-litre chest freezer with PCM cladding is used. The quantity of low-temperature PCM was varied, and the energy efficiency of the system, temperature distribution inside the refrigerated space, and on-off cycles of the compressor were studied to ensure its technical feasibility. The results from the study showed that the use of PCM could run the system during non-sunshine hours with an 8-15% reduction in energy consumption. The pulldown time was promising, and the off-cycle time of the compressor was long, which ensures that the system can work at the desired temperature during the off-sunshine hours. The temperature distribution inside the freezer and food compartments of the refrigerator for various quantities of PCM was found to be from -14 to -16°C and from 1 to 8°C, respectively. Moreover, the calculated total equivalent warming impact was 15-60% lower than the conventional system. A detailed study on the economic benefits and risk analysis can be conducted to mature the technology