Technical-Economic Analysis and Optimization of Maisotsenko GT-ORC under Intercooling

The Maisotsenko gas turbine cycle (MGTC), integrated with a combined aftercooling and regenerative saturator, has the potential to challenge traditional wet air turbine cycles. However, its large water consumption limits its applicability. By integrating an intercooler and Organic Rankine Cycle (ORC) into the MGTC, this study proposes a comprehensive design of IMGT-ORC, which can adjust the water capacity of the saturator, and utilize the sensible heat of cooling water and the latent heat of evaporation in exhaust gas to achieve water and energy saving. Firstly, a sensitivity analysis was conducted to investigate the effects of various parameter variations on thermodynamic and economic indicators under different temperature drop ratios. Subsequently, a multi-objective optimization approach was employed to seek for an optimal balance between economic and environmental benefits. The results showed that either the intercooler or ORC integration can improve the thermal efficiency of the system. In the case of joint setting, the thermal efficiency is relatively increased by 6.89% and the water consumption is relatively reduced by 89.07%. Moreover, although high temperature drop ratio reduces the output of ORC, it enhances the energy efficiency of the top cycle. In terms of cost control, ORC integration may increase the levelized cost of electricity (LCOE) slightly, while the intercooler integration helps offset the increase. Finally, the optimization results show that using the optimal parameter combination can reduce the annual equivalent carbon dioxide emissions by 11 600 tons and the annual water consumption of the power plant by 251 027 tons.