不确定信息下跨期动态的混合减排政策研究

Intertemporal dynamic hybrid policy design for emissions control with information uncertainty

企业减排成本信息不确定性是总量控制(数量政策)或排污费(价格政策)等减排政策低效的重要原因.为缓解这种单一政策低效性,本文考虑配额可储存和借贷的跨期动态情形,在总量控制交易框架引入单边上限价格约束、单边下限价格约束、双边价格约束机制,分别设计三类数量-价格相结合的混合政策.本文证明了三类混合政策的市场分散均衡均可实现排放权有效配置;在减排成本信息不可更新条件下,三类混合政策效率严格优于数量或价格政策,且双边价格约束严格优于单边价格约束的混合政策;成本信息可更新条件下,三类混合政策、数量政策和价格政策的效率等价,且可实现总成本有效.针对中国碳市场的数值模拟分析表明,混合政策比现行总量控制交易制度可产生显著成本节约,且双边价格约束的混合政策碳价波动最小.

The information uncertainty of firms’emissions abatement cost is the main reason for inefficiency of environmental management instruments,such as cap control(quantity policy)or emission charges(price policy).To alleviate the inefficiency of such unitary policy,this paper designs three types of quantity-price hybrid policy with ceiling price,floor price,and bilateral price collars in the framework of cap-and-trade with banking and borrowing mechanisms.We prove that each hybrid policy is of achieving efficient market allocation in decentralized equilibrium.In the case of non-updating information,all the hybrid policies strictly dominate the quantity and price policies,and the hybrid policy with bilateral price collars strictly dominates that with unilateral price collar.There is no difference in efficiency between hybrid policies,quantity policy,and price policy in the case of updating information,and each makes the leastcost attainable.Numerical simulation analysis of China’s carbon market shows that the hybrid policies lead to remarkable cost savings compared to cap-and-trade,and hybrid policy with bilateral price collars has the lowest carbon price volatility.