Demystifying the carbonisation threat of unclean energy consumption: evidence from N-11 emerging economies

Purpose This study aims to investigate the environmental consequences of non-renewable energy consumption in the context of rapid industrialisation and urban expansion in the Next Eleven (N-11) emerging economies, focusing on the carbonisation threat posed by various fossil-based energy sources. Design/methodology/approach Non-renewable energy sources (coal, petroleum, natural gas and nuclear) are disaggregated for analysis over the period 1993–2022. A composite energy index was constructed using principal component analysis to quantify systemic environmental impacts. The feasible generalized least squares method and method of moments quantile regression (MMQR) were applied to capture both average and distributional effects. To address endogeneity, we explicitly employed both instrumental variable estimation and dynamic panel generalized method of moments as complementary strategies. Findings All non-renewable sources were found to significantly increase environmental emissions, with petroleum emerging as the most harmful due to its role in transportation. The composite index confirms the aggregate detrimental impact. MMQR reveals heterogeneity in emissions responses across quantiles. Practical implications The findings highlight the urgent need for N-11 countries to transition toward renewable energy sources, enhance energy efficiency and implement supportive policy reforms that can mitigate emissions and promote sustainable growth. Originality/value This study provides a novel empirical approach by integrating PCA-based composite indexing with quantile regression techniques, offering fresh insights into the differentiated environmental effects of unclean energy and the policy urgency of clean energy adoption in emerging economies.