随着我国碳排放交易市场的建立和发展,在碳排放约束下逐步降低单位产出的碳排放水平成为企业生产经营管理中的中长期约束性目标。本文在一个多周期决策模型中研究了配额-交易机制下企业的最优动态批量生产、碳排放权交易和减排投资联合决策问题。生产商在整个决策周期期初决定是否进行减排投资以及投资规模,根据每个周期的生产计划决定减排设备的运行计划。根据节能减排技术的特点,本文假设生产商运行减排设备时不仅降低了产品的单位生产碳排放量,而且降低了产品的单位生产成本。本文基于广义Benders分解法对模型进行了最优性分析,得到了最优生产决策和最优减排投资决策的一些基本性质,并通过数值实验分析了碳排放配额和碳排放权价格对生产商总成本、总排放以及减排投资决策的影响。本文的数值实验分析结果发现:(1)当碳交易市场上的碳排放权充足时,减少碳排放配额或改变碳排放配额的分配方式并不能影响生产商的碳排放水平;(2)碳排放权价格是影响生产商的碳排放水平和减排投资规模的关键因素;(3)随着碳排放权价格的上升,即使拥有足够的碳排放配额,生产商仍会不断提高减排投资规模以获得减排收益。研究结果对碳排放交易体系下生产企业进行减排技术投资具有较强的管理启示。
With the establishment and development of China's emissions trading market, the reduction of carbon emissions intensity has become a medium and long term mandatory target in companies' production operations management. A dynamic lot sizing model is proposed to investigate the optimal production, emissions trading and abatement investment decisions of a manufacturer under cap-and-trade. At the beginning of the planning horizon, the manufacturer determines the optimal abatement investment decisions, including the timing of investment in an abatement technology and the optimal abatement capacity. In each period, the manufacturer decides the optimal emission abatement size according to the production planning. It is assumed that the abatement technology can reduce both carbon emissions and energy consumption in the production process. Based on the generalized Benders decomposition approach, the dynamic model is analyzed and some properties of the optimal solution are derived. Numerical experiments are conducted to examine the effects of emission cap and emission allowance price on the manufacturer' s total cost, total emissions level, and the optimal abatement investment decisions. It is found that: (1) when the supply of emission allowances in the market is abundant, reducing the carbon cap or changing the initial allocation rule of free emission allowances will not reduce the manufacturer's carbon emissions level; (2) carbon emission allowance price is the key factor to control the manufacturer's carbon emissions level and abatement capacity; (3) with the increase of carbon price, the manufacturer will expand the abatement capacity even if it has already held enough allowances to cover all its emissions. Our research provides useful managerial insights for manufacturing firms to make investment in carbon emissions abatement under the cap-and-trade system.