ABSTRACT

The Paris Agreement calls on countries to pursue efforts to limit global average temperature rise to 1.5°C. We derive a 2016–2050 emission budget for the EU Emissions Trading System (EU ETS) based on cost-effectiveness criteria aimed at achieving the 1.5°C target with a 50%–66% probability, and translate it into a cap reduction path. We show that, under current ETS parameters, the vast majority of this budget will be consumed by 2030. Meeting the budget under current 2030 EU ETS parameters would require drastic – and probably unrealistic – additional efforts after 2030. We derive a cost-effective scenario delivering a smoother and more credible emission pathway. We show that recently increased EU targets for renewable energy and energy efficiency, along with national coal phase-out policies up to 2030 provide cap adjustment potential. If the cap is adjusted to reflect these policies and if phased-out coal capacities are fully substituted through renewable energy, emissions in ETS sectors could decline by 57% through to 2030. This approximates our cost-effective scenario and translates into a linear reduction factor (LRF) for the cap of 3.6% for the period 2021–2030.

Key policy insights

• Paris Agreement-compatible emission budgets can serve as a guideline to define the minimum requirement for emission reductions in the EU ETS.

• The globally cost-effective emissions budget for EU ETS sectors in line with limiting global warming to 1.5°C is about 30 Gt CO₂e for 2016–2050.

• During the next decade the annual emissions cap must decrease much faster than currently planned to meet the cost-effective budget.

• Achieving a globally cost-effective emissions path requires that the linear reduction factor (LRF) of the EU ETS cap for 2021–2030 is raised from currently 2.2% to at least 4%.

• Incorporating EU targets for renewable energy and energy efficiency, as well as national coal phase-outs, enables an increase of the LRF for 2021–2030 to 3.6% without an additional abatement burden on EU ETS installations.

摘要

《巴黎协定》呼吁各国努力将全球平均气温上升限制在1.5°C以内。我们基于成本效益标准得出了欧盟排放交易体系（EU ETS）的2016–2050年排放预算，旨在以50％–66％的概率实现1.5°C的目标，并将其转化为减排上限的途径。我们表明，根据当前的ETS参数，到2030年，该预算的绝大部分将被消耗。要达到当前2030年的欧盟ETS参数的预算，则需要在2030年后做出巨大的努力，而且可能是不现实的。我们得出了一种具有成本效益的方案提供更平滑，更可靠的排放途径。我们表明，最近提高的欧盟关于可再生能源和能源效率的目标，以及直至2030年的国家煤炭淘汰政策都提供了上限调整的潜力。

重要政策见解

• 符合《巴黎协定》的排放预算可以作为指导原则，以定义EU ETS中的最低减排量要求。

• 为将全球变暖限制在1.5°C以内，EU ETS部门的全球具有成本效益的排放预算在2016-2050年约为30 Gt CO ₂ e。

• 在接下来的十年中，年度排放上限的降低速度必须比目前计划要快得多，才能实现具有成本效益的预算。

• 要实现具有全球成本效益的排放路径，需要将2021-2030年欧盟排放交易体系上限的线性降低因子（LRF）从目前的2.2％提高到至少4％。

• 结合欧盟关于可再生能源和能源效率的目标以及国家逐步淘汰煤炭，可以使2021-2030年的LRF增加到3.6％，而不会给欧盟ETS安装带来额外的减排负担。