Unveiling sectoral eco-efficiency disparities in Africa: An integrated input-output network DEA approach to GHG emissions and policy pathways

Africa's heterogeneous economic landscape poses challenges in reconciling economic growth with environmental protection. To improve African countries' alignment with Sustainable Development Goals (SDGs), it is important to develop a framework for the evaluation of eco-efficiency performance in African countries. This study proposes a new framework combining network Data Envelopment Analysis (for eco-efficiency analysis), Multi-Regional Input-Output table (for sectoral supply chain analysis), GHG footprint matrix (for environmental impact assessment) and Theil index (for eco-efficiency inequality analysis). The framework of this study, to the best of our knowledge, cannot be found in existing studies. Empirically, this study applies the framework to 54 African countries from 2015 to 2019. Results of eco-efficiency evaluation show differences in country-level efficiency performance and divergence in sector-level efficiency trends. As for the GHG footprint results, the agriculture sector shows a stable trend of GHG footprints, while the contribution of GHG emissions from accommodation and manufacturing sectors present a significant downward trend. Overall GHG footprints show a downward trend across African countries, while divergent patterns persist. Results of Theil index decomposition reveal increasing eco-efficiency inequality within sectors, with most of the inequality resulting from intra-group differences in high-eco-efficiency economies. Key policy implications include improving investment in sustainable technologies, enhancing regulations to restrict GHG emissions, and fostering public-private partnerships. The findings advocate for further research on long-term strategy impacts, broader geographical studies, and comparative global analyses to support sustainable development and environmental resilience in Africa.