Parametric study on maximum transportable distance and cost for thermal energy transportation using various coolants

Highlights: • The possible distance and cost for thermal energy transportation were evaluated. • Analytical model for heat and mass transfer through pipe was developed. • Simplified method for cost estimation was employed. • KClMgCl₂ and water are appropriate coolants for thermal energy transportation. - Abstract: The operation temperature of advanced nuclear reactors is generally higher than commercial light water reactors, and thermal energy from advanced nuclear reactor can be used for various purposes, such as district heating, desalination, hydrogen production and other process heat applications. The process heat industry/facilities will be located outside the nuclear island due to safety measures. This thermal energy from the reactor must be transported a fair distance. In this study, the analytical analysis was conducted to identify the maximum distance that thermal energy could be transported using various coolants such as molten-salts, helium, and water by varying the pipe diameter and mass flow rate. The cost required to transport each coolant was also analyzed. The coolants analyzed are molten salts (such as: KClMgCl₂, LiF-NaF-KF (FLiNaK) and KF-ZrF₄), helium, and water. Fluoride salts are superior because of better heat transport characteristics, but chloride salts are most economical for higher temperature transportation purposes. For lower temperature, the water is a possible alternative when compared with helium because low-pressure helium requires extremely high pumping power, which makes the process very inefficient and economically not viable for both low and high-temperature application.