Performance Analysis of a Solar-Assisted Vapor Compression Refrigeration System

Abstract

Solar-assisted vapor-compression refrigeration couples the high coefficient of performance of a conventional mechanical refrigeration cycle with a renewable electrical source whose availability generally coincides with high daytime cooling demand. This methodology paper develops a compact analytical framework for evaluating a photovoltaic (PV)-assisted vapor-compression refrigeration system without claiming new experimental measurements. The proposed system consists of a PV array, power-conditioning unit, optional battery buffer, inverter or direct-current compressor interface, and a single-stage refrigeration loop containing a compressor, condenser, expansion device and evaporator. Performance is assessed using refrigeration coefficient of performance (COP), PV power, solar fraction, grid-energy reduction and system energy balance. A representative case study is defined for an R134a vapor-compression unit delivering 1.5 kW of cooling and assisted by a 0.6 kWp PV array. Hourly solar irradiance and ambient-temperature scenarios are used to quantify how solar availability and condensing conditions influence compressor power and grid demand. The calculated daytime results show the expected trade-off: refrigeration COP decreases as condensing temperature rises, while PV contribution increases with solar irradiance. Under the stated assumptions, approximately 58% of compressor electricity during the analysed six-hour solar window can be supplied by the PV subsystem. The framework is suitable for comparative studies, preliminary sizing and experimental planning, while the literature basis is limited to publications available up to 2016.