The role of artificial intelligence and green technological innovation in shaping greener and nuclear energy efficiency: Evidence from developed and developing countries using a panel time-varying approach

Artificial intelligence (AI) and green technological innovation have become central to improving the efficiency of renewable and nuclear energy systems, particularly following the rapid acceleration of AI deployment since 2022. This study investigates the dynamic and heterogeneous effects of AI and green technological innovation, proxied by green patents, on the efficiency of renewable and nuclear energy across advanced and developing countries over the period 2000–2024. Employing a Time-Varying Interactive Fixed Effects (TV-IFE) model alongside Bootstrap Quantile Regression (BSQR), the analysis captures structural changes, cross-country heterogeneity, and distribution-specific responses that are not observable using conventional static panel approaches. The results reveal a pronounced strengthening of AI's contribution to energy efficiency in the post-2022 period, reflecting the maturation of AI-driven optimization, automation, and intelligent energy management systems. While green technological innovation initially exhibits a weak or negative effect, its impact becomes significantly positive as AI adoption deepens, indicating a strong complementary relationship between digital intelligence and green innovation. Importantly, the findings uncover substantial heterogeneity across development levels: advanced economies experience immediate and persistent efficiency gains from AI, whereas developing economies display delayed but accelerating benefits once technological and institutional thresholds are reached. The findings offer a forward-looking framework for future research, encouraging scholars to adopt time-varying methodologies, post-AI-boom datasets, and development-specific analyses when assessing the role of emerging digital technologies in energy transitions. • Artificial intelligence improves renewable and nuclear energy efficiency. • Green patents show a delayed effect, but they increase energy efficiency. • Time-varying effects were captured using a TV-IFE panel model. • Efficiency gains are different among countries and they depend on income levels. • Policy implications support AI-driven clean energy transition.