世界银行-埃塞俄比亚碳税的分配效应：可计算的一般均衡分析（英）-2023.6-40页_848kb

Distributional Effects of Carbon Tax in Ethiopia: A Summary

1. Introduction and Objectives
Ethiopia is committed to reducing GHG emissions by 68.8% below business-as-usual by 2030 under the Paris Agreement. This study uses a Computable General Equilibrium (CGE) model to assess the economic, distributional, and environmental impacts of a hypothetical carbon tax (US$20/tCO₂) under various revenue recycling schemes.

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2. Methodology
A static CGE model is constructed based on Ethiopia's 2016 Social Accounting Matrix (SAM). Scenarios vary in how carbon tax revenue is recycled, including investment, cash transfers to households (equal, proportional, or inverse to income), reductions in personal or corporate income taxes, and adjustments based on CO₂ intensity, capital account shares, or export intensity.

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3. Key Findings
Distributional Effects

• Regressive Tax: Without revenue recycling, a carbon tax is regressive, disproportionately affecting low-income households.
• Progressive Recycling Only with Cash Transfers:
  • When carbon tax revenue is distributed as cash transfers, the tax becomes progressive if transfers are equal or inversely proportional to income.
  • Progressive schemes also lead to higher CO₂ emission reductions.
• Specific Revenue Recycling Schemes:
  • Cash transfers equally or inversely proportional to income boost GDP marginally.
  • Corporate income tax cuts (especially those inversely tied to CO₂ intensity) disproportionately benefit high-income groups and reduce GDP.
  • The 'Income-Base' cash transfer (proportional to income) is the most regressive from a distributional standpoint.

Economic Effects

• GDP Impacts: Carbon tax revenue recycling to cash transfers (especially equal or inverse-income schemes) reduces GDP by approximately 0.04–0.09%. Conversely, tax cuts on personal income taxes or investment uses can mitigates GDP losses.
• Efficiency Trade-offs:
  • Tax schemes boosting GDP (e.g., personal income tax cuts) are often regressive or environmentally inferior (lower emission reductions).
  • There is no scheme that aligns all three goals (equity, efficiency, environmental performance).

Environmental Effects

• Emission Reductions:
  • CO₂ reductions are highest under progressive cash transfer schemes (equal or inverse-income transfers) and increased corporate tax cuts based on CO₂ intensity.
  • Compared to inefficient schemes (e.g., cash transfers proportional to income), clean energy investments and income tax cuts can decrease emissions by 7–7.6%.

Sensitivity Analysis
Key findings remain robust even when substitution elasticities increase by 20%, indicating consistency in model outcomes.

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4. Policy Implications

• Prioritize Progressive Revenue Recycling: Eth Ethiopia should prioritize revenue recycling mechanisms that are both progressive and economically efficient (e.g., personal income tax cuts) to balance equity and efficiency.
• Avoid Cash Transfer Schemes: While cash transfers effectively reduce inequality, they cause significant GDP losses. Such schemes may be suitable in the short term but not optimal long-term.
• Focus on Sectoral Design: Recycling based on CO₂ intensity or export performance is efficient but regressive. Policymakers must consider regional variations.

5. Limitations
Use of a 2016 SAM dataset might not fully reflect Ethiopia's current economic structure. Further studies could benefit from updated data.

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