限时补贴：最优税收及其对可再生能源补贴的启示
Time-Limited Subsidies: Optimal Taxation with Implications for Renewable Energy Subsidies
Journal of Political Economy · 2025 · [{"name": "Michael Ricks", "affiliation": []}, {"name": "Owen Kay", "affiliation": []}]
中文摘要
庇古补贴是有效率的，但期限不确定或有限的产出补贴并非庇古式补贴。我们表明，最优的限时政策还必须补贴投资，以纠正产出补贴结束后产生的外部性。此外，产出补贴的最优期限由其结束时产量的变化所刻画。在风能行业中，我们发现，在设施获得“可再生能源生产税收抵免”10年资格期结束后，发电量下降了5%–10%。这一行为反应对能源转型具有启示意义，并凸显出时间限制可能在弹性更大的行业中造成更大的扭曲。
Abstract
Pigouvian subsidies are efficient, but output subsidies with uncertain or limited durations are not Pigouvian. We show that optimal time-limited policies must also subsidize investment to correct externalities generated after the output subsidy ends. Furthermore, an output subsidy’s optimal duration is characterized by the change in production when it ends. In the wind energy industry, we find that power generation decreases by 5%–10% after the end of facilities’ 10-year eligibility for the Renewable Energy Production Tax Credit. This behavioral response has implications for energy transitions and highlights how time limits could cause larger distortions in more elastic industries.