Implementation of sustainable refrigeration technology with phase-change material storage at rural communities in Kampung Labang, Bintulu Sarawak, Malaysia: A case study

Abstract

Solar-powered refrigeration is a promising solution for ensuring sustainable access to cooling in areas with weak or off-grid electricity supply. However, conventional solar-powered fridges rely heavily on high-cost electrical battery storage and photovoltaic (PV) panels, which limit their economic feasibility in many rural settings. To address these challenges and reduce reliance on electrical storage, phase-change materials (PCMs) have been introduced as a viable thermal energy storage solution. A PCM system can be more energy-efficient than conventional solar-powered fridges because it stores excess cooling during the day and releases it during night-time or cloudy conditions. This leads to reduced dependence on electrical batteries, which are typically a major cost driver in solar refrigeration systems. Experimental validation demonstrated that PCM packs maintained an average temperature of 6.73°C in the chiller and −5°C in the freezer during low or zero solar irradiance, outperforming conventional solar-powered fridges with the same electrical battery and PV panel arrangement. The integration of PCM reduced the levelized cost of cooling to 27 cents USD/kWh, or 70% lower than conventional solar-powered fridges. In addition, this study uniquely combines technical advancements with social engagement by involving end-users through pre-installation analysis and semi-structured interviews, ensuring the system’s relevance, practicality, and acceptance. These findings highlight the importance of integrating both technical and social perspectives to accelerate the adoption and implementation of sustainable cooling technologies in off/weak-grid areas.