Conlon, William M.Venetos, Milton J.2026-03-042024-07-2520242024-05-102024978844722745710.12795/9788447227457_139https://pepa.une.es/handle/123456789/70165A liquid air combined cycle (LACC) is a hybrid energy storage system that uses cryogenic air as a storage medium. Discharge of stored energy involves the pressurization and re-gasification of the stored liquid air, sensible heating of gaseous air, and expansion of the air through a turbine that discharges to atmosphere. During discharge of stored energy, an Organic Rankine Cycle (ORC) operates as a bottoming cycle drawing low-temperature heat from the gas turbine exhaust and using the cryogenic liquid as a heat sink. The quantity of low-grade heat that can be extracted from gas turbine exhaust is constrained by the amount of heat that must be rejected from the ORC. The overall efficiency of the LACC is the net power output divided by the energy inputs, which are the electricity used to cryogenically liquefy air during charging and the fuel consumed by the gas turbine during discharging. Power output can be increased by maximizing the heat input to the ORC, potentially including the water of combustion. To relieve the constraint imposed by the limited availability of cryogenic liquid air and to maximize the heat input and power output, a novel dual condensing pressure cycle is described. The cycle includes both high and intermediate pressure turbines, with one condenser operating at intermediate pressure and the second operating at a low pressure. A fraction of the ORC working fluid is extracted at intermediate pressure and cooled by heating regasifed air. The remainder of the working fluid expands through the intermediate pressure turbine and condenses at low pressure using the cryogenic liquid air as a low temperature heat sink. The low-pressure liquid is pumped to intermediate pressure and used to directly condense the cooled fraction, whereupon the mixture is recuperated and then heated by gas turbine exhaust.Libro digitalpp. 743-750Creative Commons Attribution 4.0 International (CC BY 4.0)Creative Commons Attribution 4.0 International (CC BY 4.0)http://creativecommons.org/licenses/by/4.0/openAccess