Supercritical carbon dioxide power cycle for waste heat recovery

摘要

Aspects of the invention disclosed herein generally provide heat engine systems and methods for recovering energy, such as by generating electricity from thermal energy. In one configuration, a heat engine system contains a working fluid (e.g., sc-CO₂) within a working fluid circuit, two heat exchangers configured to be thermally coupled to a heat source (e.g., waste heat), two expanders, two recuperators, two pumps, a condenser, and a plurality of valves configured to switch the system between single/dual-cycle modes. In another aspect, a method for recovering energy may include monitoring a temperature of the heat source, operating the heat engine system in the dual-cycle mode when the temperature is equal to or greater than a threshold value, and subsequently, operating the heat engine system in the single-cycle mode when the temperature is less than the threshold value.