Life cycle assessment and CFD evaluation of an innovative solar desalination system with PCM and geothermal system

Abstract

Objective

This study introduces a novel solar desalination system supported by a parabolic trough collector (PTC) to enhance thermal efficiency and reduce temperature fluctuations. The system utilizes solar energy to purify water, mimicking the natural water cycle, while integrating Phase Change Material (PCM) to optimize thermal energy storage and utilization during nighttime or cloudy conditions. To improve system performance, the spraying unit was analyzed using the Computational Fluid Dynamics (CFD) method. Additionally, a Life Cycle Assessment (LCA) and Life Cycle Impact Assessment (LCIA) were conducted to evaluate the system's environmental impact, focusing on global warming and pollution levels. The results showed that the highest volume fraction (25.8 %) was achieved in the spraying rate of 0.75 l/min at t = 10.254 s, with CFD simulation data aligning with test data at a high accuracy level (R² > 98.2 %). The adoption of PCM reduced environmental pollutant emissions by increasing thermal energy efficiency. However, environmental pollution was significantly influenced by the use of copper pipes and cables, contributing 9.81 % to ozone layer depletion, 15.6 % to global warming, 28.9 % to non-renewable energy consumption, and 61.7 % to mineral extraction. The fresh water production from the proposed desalination system with PCM was 978 cc, with the improvement of at least 10.15 % compared to the system without PCM. The integration of PCM in the desalination system improved thermal performance, reduces energy waste, and improves sustainability by lowering pollutant emissions. Compared to conventional electrical desalination systems, the proposed system demonstrates superior efficiency due to its reliance on renewable energy.