Thermal Energy Storage Battery

About

This invention consists of a thermal energy battery based on a concept that integrates: an enhanced cementitious section, dual-operation thermosyphons and rapid heat transfer plenums for direct-steam thermal storage. The enhanced cementitious section consists of concrete formulation that mitigates strength and thermal properties degradation at high operational temperatures. The concrete media is enhanced through combination of constituents that may include but is not limited to: fibers, high thermal conductive aggregates, and supplemental cementitious materials. The thermosyphons allow dual operation as evaporators and condensers for fast energy charge and discharge. The heat transfer plenum contains heat transfer elements for rapid charging and discharging of the thermal battery. This direct-steam storage concept represents a cost-effective competitive option to conventional molten-salt-based energy storage systems. The concept targets: high temperature (400 deg. C), high power capacity (MJ/sec), high storage capacity (MWh). In this concept heat transfer media from the power plant is used to charge a concrete section via the evaporative end of the thermosyphons, housed in a sectional plenum. The heat transfer media can be water from the plant in liquid or vapor phase, supercritical carbon dioxide (sCO2) in new advanced power cycles or an indirect heat transfer fluid such as thermal oil. Heat can be stored in the concrete module for long periods of time. At demand, the stored heat can be rapidly discharged back into the plant via the condensing end of the thermosyphons and heat transfer enhanced plenum. The invention is designed for modular deployment, allowing for easy deployment of large energy storage densities and capacities at the MWh level. The subject invention can be used in coal-, oil- and natural gas-fired energy systems, as wells as in other high-temperature industrial applications, such as cement kilns, and glass, aluminum and steel furnaces. Variants of the subject invention include the use of thermosyphons filled with a range of operating media, such as Dowtherm, water, sodium-potassium, aluminum bromide to accommodate a range of operating temperatures. Heat pipes can alternative be used in lieu of thermosyphons to facilitate different geometries and arrangements. Other variants of the subject invention include applications where the concrete section is replaced by other heat transfer means, instead of sensible heat transfer in concrete, such as latent heat transfer using phase change materials, phase change materials infused in high conductivity matrices, and thermochemical heat transfer using metals oxides and alkaline earth metals in packed and fluidized bed arrangements.