Linking external debt and renewable energy to environmental sustainability in heavily indebted poor countries: new insights from advanced panel estimators.

There are numerous studies on the linkage between renewable energy and environmental sustainability. These studies have tried to show how renewable energy is relevant in curbing the environmental difficulties associated with climate change. However, the role of external debt is seldom considered in the nexus. As such, this study applies advanced estimation techniques compatible with two core panel data issues (cross-sectional dependence and heterogeneity) to investigate the role of external debt in the growth-energy-emissions relationship in thirty-three heavily indebted poor countries (HIPC) from 1990 to 2015. The findings of the study reveal that economic growth increases emissions thereby degrading the environment, while renewable energy ensures environmental sustainability by abating CO2 emissions. Further findings from the study suggest that external debt increases CO2 emissions in HIPC across the three estimators. The country-wise results reveal that economic growth deteriorates the environment in all the countries except in Burkina Faso, Congo, Mali, Mauritania, Nicaragua, and The Gambia. Also, the result reveals a bidirectional causal relationship between external debt and economic growth, CO2 emissions and economic growth, external debt and CO2 emissions, and renewable energy and economic growth. This study argues that the consumption of clean energy sources and strong institutional quality could help mitigate the trade-offs between economic growth and environmental quality and also curtail the negative effects of external debt on the environment. The limitations of the study and directions for future research are discussed.