Analysis of partial heating supercritical CO2 cycles bottoming small-power gas turbine units

Supercritical CO2 power systems are investigated as bottoming cycles of combustion turbines, limiting the power output of the topping cycle to the range of 5-10 MW. Actually, the conventional combined cycle with a bot-toming steam power plant is not convenient for a number of commercial combustion turbines. In particular, the partial heating supercritical CO2 cycle, with a limited number of components compared to other cycles, is the layout chosen in this work based on a relevant trade-off between heat recovery and cycle efficiency. Single-stage radial turbomachines are selected for the power system components, considering the investigated range of power production. Focusing on a number of cases, all related to commercially available combustion turbines, interesting considerations about the size of both turbomachinery and heat transfer equipment composing the supercritical CO2 power cycle are possible thanks to scaling effects. However, proposing a customized supercritical CO2 cycle for each combustion turbine is anything but a reasonably sound solution. Thus, a properly unified one-size-fits-all supercritical CO2-based power system should be duly considered from a more practical point of view.