Energy harvesting: role of hybrid nanofluids

The limited thermal energy transportation capability of conventional fluids curbs the energy-harvesting potential of renewable energy-harvesting systems. Efficient photothermal conversion is subject to the thermophysical and optothermal characteristics of the working fluid. Hybrid nanofluids present superior thermophysical and optothermal features among conventional and modern thermofluids. This chapter presents an extensive description of hybrid nanofluid preparation methods and characteristics. The role of hybrid nanofluids in direct and indirect energy-harvesting systems is thoroughly discussed in this chapter along with the scientific explanation of results and characteristics influencing the system performance. Underlying challenges associated with hybrid nanofluids include intricate and inconclusive physical science, instability of colloidal suspensions, increased frictional losses and resulting pressure drop, fouling due to heating and cooling cycles, and high production costs. Instability is the prime concern associated with hybrid nanofluids. A deep insight into these complexities has also been presented in this chapter.