Nanofluids Based on Pd Nanoparticles and a Linear Silicone-Based Fluid: Toward Highly Efficient Heat Transfer Fluids for Concentrated Solar Power

Meeting the growing energy demand with the lowest environmental impact is one of the greatest challenges facing our society. To this end, improving the efficiency of solar energy technologies is a must. In this work, nanofluids based on a linear silicone-based fluid and Pd nanoparticles were prepared. The linear silicone-based fluid has been designed for use in concentrated solar power involving parabolic trough collector technology (CSP-PTC). The nanofluids showed high physical and chemical stability. In addition, the Pd-based nanofluids showed enhanced isobaric specific heat and thermal conductivity values without a significant increase in viscosity. The increase in the specific heat with respect to the base fluid was about 5.5%, while thermal conductivity increased by 8.5%. Analyzing the interactions between the nanoparticles and the base fluid provides a clearer understanding of the improvements in these properties. Finally, the properties measured were used to analyze the performance of the nanofluids in CSP-PTC, considering the collector and the exchanger efficiency. The overall efficiency improved by about 50%, which is a promising result.