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.
For a more detailed description of these cycles, click the link below.
Learn about the STEP pilot plant project.