Hintermayer Martin
Department of Economics and Institute of Energy Economics, University of Cologne, Vogelsanger Strasse 321a, 50827 Cologne, Germany.
Energy Policy. 2020 Dec;147:111905. doi: 10.1016/j.enpol.2020.111905. Epub 2020 Sep 23.
Despite the reform of the European Emissions Trading System (EU ETS), discussions about complementing it with a carbon price floor (CPF) are ongoing. This paper analyzes the effect of a European CPF in the reformed EU ETS using a Hotelling model of the EU ETS, amended by the market stability reserve (MSR), and the cancellation mechanism. Two CPF designs are compared: (1) a buyback program and (2) a top-up tax. The buyback program sets a minimum price for the allowances from the implementation year onwards. After the announcement, firms anticipate the CPF, which immediately increases the carbon price to the discounted CPF level. Therefore, firms emit less and bank more allowances, leading to more intake into the MSR, and more cancellation of allowances. The top-up tax imposes a tax on emissions, which enhances the market price of allowances to the CPF level from the implementation year onwards. Firms increase their short-run emissions in anticipation of the upcoming tax. Only after the implementation year firms start to lower their emissions. Thus, the effect on aggregate cancellation is ambiguous. Despite being equivalent in a static setting, the design choice for the CPF matters in a dynamic context, such as the EU ETS.
尽管欧洲排放交易体系（EU ETS）进行了改革，但关于用碳价下限（CPF）对其进行补充的讨论仍在继续。本文使用经市场稳定储备（MSR）和注销机制修正的EU ETS的霍特林模型，分析了欧洲CPF在改革后的EU ETS中的影响。比较了两种CPF设计：（1）回购计划和（2）追加税。回购计划从实施年份起为配额设定最低价格。宣布后，企业预期到CPF，这会立即将碳价提高到贴现后的CPF水平。因此，企业排放减少，储存更多配额，导致更多配额进入MSR，并更多地注销配额。追加税对排放征税，从实施年份起将配额的市场价格提高到CPF水平。企业预期即将到来的税收，会增加其短期排放。只有在实施年份之后，企业才开始降低排放。因此，对总注销量的影响是模糊的。尽管在静态环境中是等效的，但CPF的设计选择在动态环境（如EU ETS）中很重要。
