Nanoparticles when added to heat transfer fluids increase their performance. The solid nanoparticles conduct heat better than the liquid. Nanoparticles work best because they stay suspended in liquids longer than larger particles. They also have a much greater surface area, which is where heat transfer takes place. The smaller the particle, the greater its ability to enhance heat transfer. Nano-additives, including nanoparticles and nanopowders, could be utilized to enhance heat transfer from solar collectors to storage tanks.