A review of nanotechnology fluid applications in geothermal energy systems

Geothermal energy is a high potential energy source that can provide heat and power with minimal emissions. Recent advances in nanotechnology show that nanoparticles, such as CuO, TiO2, Al2O3, and Ag suspended in water, can enhance the heat transfer coefficient and rate. Here, we present a comprehensive review of nanotechnology use in closed geothermal heat pumps and heat exchangers. The study comprises: (i) detailed quantification of the effects of different parameters on a liquid suspension, including nanoparticle thermal conductivity, viscosity, volume fraction, density, specific heat capacity, mass flow rate, nanoparticle shape and size, Brownian motion, pressure drop, and friction factor; and (ii) an economic analysis of the benefits related to using of nanofluids in geothermal applications. We show that the overall performance of ground source geothermal systems improves through the use of low volume fractions of nanoparticles in suspension.

Automated summary

Geothermal energy is a highly promising energy source with minimal emissions, and recent advances in nanotechnology have shown that the use of nanoparticles in water suspensions can enhance heat transfer in geothermal systems. This comprehensive review explores the effects of various parameters on liquid suspensions and provides an economic analysis of the benefits of using nanofluids in geothermal applications. The study concludes that the overall performance of geothermal systems can be improved by incorporating low volume fractions of nanoparticles.