Thermal energy storage system and media

Abstract

The present disclosure is directed to materials that can be used in a heat storage and transfer, and an improved method for storing thermal energy which includes a high heat capacity thermal energy storage system using pumped or flowing metallic phase change materials (MPCs). Heat is added by pumping a cold fluid of MPCs mixed with a fluid media such as a molten glass and/or salt from a tank through a heat exchanger, solar receiver, or electrical heater cell and returning the heated fluid to a tank, or solid MPCs can be transported physically, or via gas transport such as entrained flow or a circulating fluid bed. In the heat exchanger, heat can optionally be transferred directly to a counterflowing gas or other fluid, or indirectly through heat exchanger walls to a working fluid, which can be steam, COor sCO, He, H, process gas, and/or heat transfer fluid. The MPCs (encapsulated MPCs, non-coated MPCs) are solid-liquid and/or solid-solid phase change particles, salts, metals, or other compounds with a melting point between the hot and cold fluid temperatures, and can optionally include high heat capacity, and/or energy absorbing (IR and divisible) nanoparticles.