Achieving carbon neutrality has become a central policy objective for emerging economies, particularly the BRICS countries-BRICS (Brazil, Russia, India, China, and South Africa) which collectively account for a substantial share of global carbon emissions and energy consumption. The transition toward green energy, rapid technological innovation, and the expansion of green finance mechanisms are increasingly viewed as critical drivers of sustainable development and environmental improvement. However, empirical evidence integrating these three dimensions within a unified analytical framework for BRICS remains limited. This study examines the contribution of green energy transition, technological innovation, and green finance to achieving carbon neutrality in BRICS countries using a Pooled mean group auto regressive distributed Lag (PMG ARDL) framework and Dumitrescu–Hurlin panel causality analysis. The results indicate that green energy transition significantly reduces carbon emissions in both the long run (−0.45) and short run (−5.65), emphasizing the importance of shifting toward renewable energy sources. Technological innovation exerts a significant negative effect in the long run (−0.17), reflecting efficiency gains and cleaner production, although its short-run impact remains insignificant. Similarly, green finance improves environmental quality in the long run (−0.10) by supporting low-carbon investments, while short-run effects are statistically insignificant due to adjustment frictions. Economic growth increases emissions in the long run (0.43), confirming the scale effect, whereas trade openness reduces emissions (−0.87), indicating the role of technology diffusion. The error correction term (−0.76) confirms a strong convergence toward long-run equilibrium. The causality analysis reveals unidirectional causality from green energy transition, technological innovation, and green finance to carbon emissions, while bidirectional causality exists between economic growth and emissions, highlighting a feedback mechanism. Policy implications suggest that BRICS economies should strengthen green financial systems, accelerate renewable energy adoption, promote innovation-driven sustainability, and design growth strategies that decouple economic expansion from environmental degradation.