Aeroderivative gas turbine integrated with supercritical CO2 cycle for gas-to-power: Comprehensive assessment and optimization

Grids with high renewable energy penetration require seasonal energy storage and flexible power generation, creating opportunities for advanced gas turbine combined cycle (GTCC) systems. This study proposes a power-to-gas-to-power pathway, in which aeroderivative gas turbines integrated with a supercritical CO2 cycle (SCC) serve as the discharge unit, utilizing e-methane as the energy carrier. For a deeper understanding of the integrated system, a comprehensive evaluation framework is developed based on a representative system architecture. Extending the waste heat recovery assessment into the exergy domain shows that CO2 flow-splitting not only improves thermal exergy recovery but also enhances the SCC's thermodynamic perfection (from 56.7 % to 61.0 %). The combined cycle exhibits superior overall performance across energy, exergy, economic, and environmental dimensions compared to standalone gas turbines. Without discretization, thermal conductance estimation errors in the recuperator and cooler exceed 50 %, whereas using only 10 segments reduces them to <1 %. Exergoeconomic analysis employing SCC-specific component cost correlations indicates that reducing the temperature difference in the heater and recuperator is economically beneficial, as evidenced by exergoeconomic factors below 40 %. An optimal gas turbine maximum temperature is identified to minimize the levelized cost of electricity, and a CO2 split ratio between 0.65 and 0.68 maximizes system efficiency. Integrated multi-objective optimization further improves the system efficiency to 51.3 %. Moreover, it reveals that the efficiency-cost trade-off is dominated by exhaust gas-related parameters, particularly the gas turbine pressure ratio. The proposed pathway and associated analyses offer insights for advancing next-generation GTCC technologies.