A case study of cascade supercritical CO2 power cycle for waste heat recovery from a small gas turbine

• A single heated cascade sCO 2 cycle is studied as bottomer of a 4.7 MW gas turbine. Around 1500 kW net electric power can be recovered by the -based technology. The specific cost considered technology around 2000 $/kW. Performance investigated similar to one partial heating cycle. Driving compressor at same rotational speed turbines not possible. Among technological solutions that applied waste heat recovery, supercritical CO (sCO ) represents an innovative option. This work studies performance system 5 MW-class turbine and follows former study authors about number parametric analyses has been carried out with attention paid selection (i) minimum maximum pressures, based on Mach selected avoid highly loaded turbomachinery, (ii) temperature, (iii) design parameters such temperature difference cold side primary heater, recuperator effectiveness single-stage radial-type efficiency, latter calculated according Aungier’s correlations taking actual size running conditions into account. results this suggest figure so different from output previously for well technology, which $/kW, lower than possible competing recovery applications organic Rankine Nevertheless, architecture in needs two rotate shaft, but driving possible, emerges preliminary considerations turbomachinery impellers.