Development and Performance Evaluation of a Dual-Loop Solar Hot Water Supply System with a Vacuum Tube Collector, a Phase-Change Heat Exchanger and Automated Control
Year: 2026
Type: conference-paper
Abstract: This article reviews the development and performance evaluation of a dual-loop solar hot water system featuring a vacuum tube collector, a phase-change heat exchanger, and automated control. The proposed system includes a vacuum solar collector with a multilayer selective coating, a composite capillary tube, a circulation pump with adjustable speed, an ethanol-based phase-change heat exchanger, temperature, pressure, and water level sensors, a microprocessor controller, protection against overheating and freezing, as well as a solar panel for off-grid power supply. The research methodology is based on thermal modelling of solar energy absorption processes, heat transfer in the primary and secondary loops, assessment of heat losses, the efficiency of the phase-change heat exchanger, and the overall system efficiency. The computational analysis was performed for a solar radiation range of 400–1000 W/m2. The results show that as solar radiation increases, the useful thermal power rises from 554 to 1546 W, and the collector efficiency increases from 69.3% to 77.3%. The efficiency of the phase-change heat exchanger ranges from 89.9% to 93.0%, confirming stable heat transfer to the secondary loop. Compared to a conventional system, the proposed design provides an increase in collector efficiency from 65% to 77%, an increase in heat exchanger efficiency from 85% to 93%, and a reduction in heat losses from 180 to 108 W, which is approximately 40%. The results obtained confirm the promising application of an integrated dual-loop solar installation for energy-efficient and autonomous hot water supply.
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W7224107489