New Working Fluids for Energy Applications

New working fluids for energy applications are being developed to improve efficiency, safety, and environmental performance of energy systems. These fluids are used in power cycles, refrigeration, heat pumps, thermal energy storage, and waste heat recovery systems. Emerging working fluids include low-global-warming-potential refrigerants, supercritical fluids, nanofluids, ionic liquids, and organic compounds. They offer enhanced thermophysical properties such as higher heat transfer coefficients, better thermal stability, and lower environmental impact. Selection of appropriate working fluids is critical for optimizing system efficiency and reducing emissions. Research focuses on fluid compatibility, stability, toxicity, and lifecycle performance. New working fluids enable advanced energy technologies such as organic Rankine cycles, supercritical CO? systems, and next-generation cooling technologies, supporting sustainable and high-performance energy applications.