Investment versus Output Subsidies: Implications of Alternative Incentives for Wind Energy
利用自然实验和工具变量法，研究发现投资补贴使风电场发电量比产出补贴低10%-12%，且产出补贴在多数目标下更具成本效益。
This study examines the choice between subsidizing investment and subsidizing output to promote socially desirable production. We exploit a natural experiment to estimate the impact of subsidy margin on the productivity of wind farms. Using instrumental variable and matching estimators, we find that investment subsidy claimants produce 10%–12% less power than they would have under the output subsidy. Accounting for extensive margin effects, we show that output subsidies are more cost-effective than investment subsidies over a large range of output targets.