Nano-engineered pathways for advanced thermal energy storage systems

Nearly half of the global energy consumption goes toward the heating and cooling of buildings and processes. This quantity could be considerably reduced through the addition of advanced thermal energy storage systems. One emerging pathway for thermal energy storage is through nano-engineered phase change materials, which have very high energy densities and enable several degrees of design freedom in selecting their composition and morphology. Although the literature has indicated that these advanced materials provide a clear thermodynamic boost for thermal energy storage, they are subject to much more complex multiscale governing phenomena (e.g., non-uniform temperatures across the medium). This review highlights the most promising configurations that have been proposed for improved heat transfer along with the critical future needs in this field. We conclude that significant effort is still required to move up the technological readiness scale and to create commercially viable novel nano-engineered phase change systems.