Molten salt composition and composites for improved latent heat thermal energy storage

Abstract

The growing concern over nonrenewable fuel sources, coupled with the continued increase of global energy demand has incentivised research into numerous new and pre-existing renewable energy sources. Concentrated solar thermal (CST) takes advantage of the high heat capacity of molten salts to provide an alternative solar solution to photovoltaic cells that allows reduced downtime through heat storage for use during suboptimal conditions. This meta-study examines the effectiveness of various eutectic Molten Salt compositions and materials as thermo-physical augmenters, with a focus on improved thermal conductivity when composited with molten salts as a method of enhancing the efficiency of concentrated solar thermal storage technology. The study is based on literature retrieved from scientific databases to investigate information available about enhancing LHTES technology. Research into carbon composites such as Expanded Graphite (EG) exhibits promising results revealing thermal conductivity increases as high as 40% in eutectic salt materials, however inconsistencies in measurements and materials used reveal a need for a greater analysis. Although molten salt thermal storage systems are not optimal in their current state, indication was found that composite storage mediums could potentially solidify their spot as a viable renewable energy source.