Novel and enabling concepts are being investigated with the potential to achieve dramatic improvements in the cost and performance of coal-based power systems in the long term. The research focus currently includes enabling high-efficiency supercritical CO2 (sCO2) power cycles and pressure gain combustion (PGC).
sCO2 Power Cycles
Integration of sCO2 power cycles has the potential to further improve efficiency and cost of electricity (COE) power generation systems. Currently targeted concepts include the integration of oxy-fuel combustion with an sCO2 power cycle. The sCO2 power cycle operates in a manner similar to other power cycles but uses CO2 as the working fluid in the turbo-machinery rather than steam and offers the potential for significant improvements in the efficiency and capital costs associated with oxy-fuel power generation. Research and development (R&D) is needed to design heat extraction components in oxy-fuel combustion units optimized to the sCO2 power cycle, as well as recuperative heat exchangers, which will help to increase the cycle efficiency.
Pressure Gain Combustion
PGC has the potential to significantly improve combined cycle performance when integrated with combustion gas turbines by realizing a pressure increase versus a pressure loss through the combustor of the turbine. While conventional gas turbine engines undergo steady, subsonic combustion, resulting in a total pressure loss, PGC utilizes multiple physical phenomena (including resonant pulsed combustion, constant volume combustion, or detonation) to affect a rise in effective pressure across the combustor, while consuming the same amount of fuel as the constant pressure combustor. Current R&D is focused on development of rotating detonation engines (RDE), understanding how non-idealities in RDEs affect operability and efficiency, improving modeling tools to predict the performance of PGCs, attaining further basic understanding of detonation-inhomogeneity interaction, and aiding in improving combustor performance.