Assessment of a Solar Powered Refrigerator Equipped with Thermal Storage for a Dairy Application
Abstract
Typical agro-food value chains are equipped with electric refrigeration systems. In many non-industrialized countries, the cold chain is often not guaranteed due to lack of electricity access or unreliable electricity grids. In such cases, refrigeration systems must be equipped with electrical backups or other form of energy storage. This study analyses the use of a commercial available vapour-compression refrigerator for small-scale cheese processing systems. The studied horizontal refrigerator of 350 litres capacity is powered by photovoltaic panels which provide electricity to a DC compressor. Encapsulated phase change materials were incorporated to the system as energy storage option, for a reliable operation at temperature at 11°C. This operating temperature is suitable for the analysed product, but it is also suitable for other agro-food applications, such as the preservation of fruits and vegetables. In particular, this study evaluates the incidence of the incorporation of PCM on the stratification temperature inside the cold space, the elevation time of the temperature of refrigerated product, the number of off-on operations of the compressor, the COP of the system, and the sizing of the conventional storage system with electrical batteries.