Modelling and Simulation of a PV Driven Refrigerator with Phase-Change Materials in the Internal Walls
Abstract
Refrigeration systems driven by photovoltaic energy are a useful solution for those regions of developing countries in which there is no electrical supply, or this supply is unreliable. These systems usually store energy through use of electrical lead-acid batteries. However, other energy storage options, with lower environmental effects, such us thermal energy storage, can be applied. This study presents a model and simulation of a horizontal direct-current, compression refrigerator, which is driven by a photovoltaic sub-system. The system has latent thermal energy storage, through the incorporation of a slab with phase-change materials, next to the evaporator-wall, inside the refrigerator. System performance was analysed with a product temperature of 11ºC, and includes three materials. One was water, and the others were phase-change materials, with average melting temperatures of 5°C and 9°C, respectively. Results indicate that the lead-acid battery capacity in such a PV-driven refrigerator can be reduced between 16% and 78%, in accordance with system operating conditions and the phase change material selected for the studied application.