Amid intensifying energy challenges and ecological constraints, promoting green economic transformation has become vital for achieving sustainable growth and reducing reliance on resource-intensive development models. This study explores the heterogeneity of green economic efficiency (GEE) between the Group of Seven (G7) and Emerging Seven (E7) economies using a three-stage super-efficiency SBM-DEA that integrates non-radial measurement, effective unit ranking, and stochastic noise correction. A Tobit regression model is further employed to assess the nonlinear effects of the technological innovation and natural resource rents on GEE. The results indicate that: (1) G7 economies consistently outperform E7 economies in GEE, although the efficiency gap has gradually narrowed since 2016. Within E7 economies, marked efficiency disparities persist, reflecting limited technological diffusion and weaker innovation capacity. (2) G7 economies exhibit synergistic improvements across management, technological, and scale efficiencies, whereas E7 economies display higher volatility and structural constraints. (3) Technological innovation exhibits a pronounced U-shaped effect on green economic efficiency (GEE), whereas natural resource rents display an inverted U-shaped relationship with GEE. These effects are more pronounced and rapidly transmitted in G7 economies, while in E7 economies they are weaker and the turning points are delayed. Further analysis indicates that industrial structure significantly constrains the impact of innovation, whereas government effectiveness does not constitute a stable moderating mechanism in either group of economies. These findings highlight the need for differentiated policy strategies to promote green economic efficiency through innovation-driven growth, efficient resource use, and institutional reform. • Measured G7 and E7 green efficiency using a three stage SBM-DEA model. • Filtered environmental and random effects through stochastic frontier analysis. • Identified U shaped GII and inverted-U NRR effects on green efficiency. • Technological innovation and resource rents led to disparity between G7 and E7. • Industrial structure will restrain the driving effect of innovation on GEE.
Li et al. (Wed,) studied this question.