The article explores the nexuses between carbon dioxide (CO2) emissions, economic growth, renewable energy consumption, and trade openness in the fast-growing MINT (Mexico, Indonesia, Nigeria, and Turkiye) and BRICS (Brazil, Russia, India, China, and South Africa) economies for the period 1990–2019. The study utilized threshold regression to provide a policy threshold on carbon emission metrics tons per capita of 0.96, 0.36, for the fast-growth emerging markets. The study also provides complementary thresholds for renewable energy consumption and trade policies. The novelty of the study is in the light of the contemporary literature that stems from the premised on providing the policymakers in the fast-growing economies with avoidable policy thresholds for CO2 emission along with the complementary thresholds on renewable energy consumption, and trade policies in the nexus between green growth and environmental degradation.