基于产出效率的中国钢铁行业碳配额分配方案

Carbon quota scheme for China’s iron and steel industry based on output efficiency

【目的】为推动钢铁行业尽快纳入碳排放交易市场,已有研究主要从成本影响角度分配钢铁企业碳配额。然而,钢铁行业碳排放量大、生产工艺复杂,过度强调成本影响易降低减排效益,不利于推动钢铁企业低碳转型。本文基于碳减排效率与产出效率,旨在设计符合中国钢铁行业发展现状的碳配额分配方案。【方法】梳理不同流程钢铁生产工序,将碳配额作为各工序连续生产的必要原料,重新得到钢铁生产流程;叠加碳配额,构建投入-产出随机前沿模型,得到钢铁行业生产效率与碳配额效率估计公式;对比不同碳配额基准值对钢铁生产工序产出率的影响,以提高效率为标准,确定中国钢铁业跨区域碳配额基准线。【结果】相较于历史排放法,基准线法更适于中国钢铁行业碳配额分配。碳配额基准线设定在行业前[30%, 50%]区间有助于提升钢铁行业总体产出率,且当碳配额基准线设定在行业前40%时的产出率水平最高。当碳配额基准线设定大于钢铁行业前50%企业碳排放值时,行业产出率随着碳排放基准线设定的增加而降低。以基准线法推进钢铁行业纳入碳排放交易市场,中国钢铁行业将在节约碳关税的同时,获得碳排放交易收益。【结论】基于产出效率分配碳配额有助于提升钢铁行业减排效益,激发钢铁行业自主减排潜力,助力中国钢铁行业全流程脱碳。

[Objective]In order to help China’s iron and steel industry to enter the carbon emission trading market,previous studies have mainly allocated carbon quotas for iron and steel enterprises from the perspective of the impact of cost.However,the iron and steel industry has large carbon emissions and complex production processes,and overemphasizing the impact of cost will easily reduce the benefits of emission reduction,which is not conducive to promoting the low-carbon transformation of iron and steel enterprises.Based on the carbon emission reduction efficiency and output efficiency,this study aimed to design a carbon quota allocation scheme that conforms to the current development situation of China’s iron and steel industry.[Methods]This study reviewed the production steps of different iron and steel production processes,took carbon quota as the necessary raw material for continuous production of each steps,and reconstructed the iron and steel production processes.By superposing carbon quota,an input-output stochastic frontier model was constructed,and the estimation formula of production efficiency and carbon quota efficiency of the iron and steel industry was obtained.Comparing the impact of different carbon quota reference values on the output rate of the iron and steel production processes,and taking efficiency improvement rate as the selection standard,this study determined the cross-regional carbon quota baselines of China’s iron and steel industry.[Results]Compared with the historical emission method,benchmarking is more suitable for the carbon quota allocation of China’s iron and steel industry.The carbon quota baselines of China’s iron and steel industry should be set in the top[30%,50%]range of the industry,and the optimal baseline should be set in the top 40%of the industry.When the carbon emission is greater than the top 50%of the industry,the production rate of the iron and steel industry decreases with the increase of the carbon emission baseline.Incorporating the iron and steel industry into China’s carbon emission trading scheme by the benchmarking method will help this industry to both save carbon tariffs and obtain a carbon market share.[Conclusion]Allocating carbon quotas based on output efficiency can help improve the efficiency of emission reduction in the iron and steel industry,and stimulate the potential of independent emission reduction in this industry.Extending the quota allocation method of this study will help the whole process of decarbonization in China’s iron and steel industry.