Evaluation of an aluminum latent heat storage system for the fluoride-salt-cooled high-temperature reactor

Abstract

Latent heat energy storage (LHS) systems offer multiple advantages over sensible heat storage systems in terms of energy density, cost, and cycle efficiency. LHS systems use a phase change medium (PCM) that transfer heat at constant temperature. The use of metallic PCMs allows LHS to be used with high-temperature heat sources, such as the Fluoride-Salt-Cooled High- Temperature Reactor, and the use of a metallic heat transfer fluid (HTF) allows for a high rate of heat transfer. In this thesis, a 0.993 GWh thermal battery (ALTA) comprised of an aluminum PCM and sodium HTF is designed and evaluated in the steady-state. A novel rod design is also proposed to accommodate aluminum expansion as it changes phases. A final capital cost of $25.00/kWh is found, suggesting that ALTA is economically competitive.