Supercritical CO2 Power Cycles

Research and development is focused on developing high-efficiency, low-cost power generation based on supercritical carbon dioxide (sCO₂)-based power cycles. Supercritical carbon dioxide power cycles operate in a manner similar to other turbine cycles, but use CO₂ as the working fluid. These cycles are operated above the critical point of CO₂ so that it does not change phases, but rather undergoes drastic density changes over small ranges of temperature and pressure. Supercritical CO₂-based power cycles have shown the potential for increased heat-to-electricity conversion efficiencies, high power density and simplicity of operation compared to existing steam-based power cycles. Supercritical CO₂ power cycles utilize small engines, are fuel- and/or heat-source neutral and are more efficient than the standard Brayton Cycle.

The focus of current research is to develop highly efficient and lower cost indirectly-heated sCO₂ power cycles that surpass the performance of advanced ultra-supercritical steam cycles and provide the technology base for directly heated sCO₂ power cycles. The direct-fired cycle can facilitate carbon capture by producing a high purity stream of carbon dioxide that is ready for use/reuse or storage. sCO₂ power systems research includes pilot plant development and testing, turbomachinery, recuperators, advanced cycle concepts, and systems integration and optimization.