Renewable energy, economic development, and ecological footprint nexus: fresh evidence of renewable energy environment Kuznets curve (RKC) from income groups

This study aims to measure the association of real economic growth per capita, renewable energy consumption, and financial development with ecological footprints (EFP) across the 155 countries of four different income groups over the period of 1990–2017. For the analysis, the unit root tests allowing cross-sectional dependency, Westerlund cointegration test, common correlated effect of mean group, augmented mean group, mean group, and Dumitrescu–Hurlin panel causality test are used. The results verify both the environmental Kuznets curve (EKC) and renewable energy environment Kuznets curve (RKC) hypotheses in the high-income group; however, other groups have not shown reliable results. Moreover, it is observed that the existence of RKC is a turning point for high-income countries, and it takes place before the turning point of the forthcoming EKC. Besides, empirical outcomes endorse the presence of long-run equilibrium and indicate that financial development has a negative and significant effect on the EFP in the case of the high-income group. In contrast, upper–middle– and lower–middle–income groups show the insignificant relationship with the dependent variable. Likewise, financial development has a positive and significant association with EFP for the low-income group. Conversely, biomass energy has a negative relationship with EFP in high- and lower–middle–income groups, while a positive association has been observed for the remaining two groups. We suppose that the study outcomes would guide the policymakers in decision-making regarding the development and usage of renewable energy to prevent environmental damages.