绿色政策规制下的航运企业减排策略转换时机决策研究

Research on timing decision of shipping companies’emission reduction strategy switching under green policy regulation

考虑国际海事组织的绿色政策要求,结合航运业绿色发展的现实需求,以减排策略转换引起的船舶航速变化为切入点,运用实物期权理论,构建了两种场景下的竞争博弈模型,探究了航运企业减排策略转换时机决策.研究发现:1)严厉的绿色政策、市场竞争和托运人对航速偏好并不总是能够激励航运企业提前进行减排策略转换.2)设备补贴总是能激励航运企业提前转换减排策略,而运营补贴仅在一定条件下才能生效,且在一定阈值范围内,设备补贴的效果总是优于运营补贴;缩短政策过渡期会使得航运企业的减排策略转换时机提前,但在特定范围内,过渡期的长短将不会对航运企业减排策略转换时机产生影响.3)当货运总规模大且增长率缓慢时,航运企业会提前进行减排策略转换;不同的设备升级环境会对航运企业的减排策略转换时机产生差异性影响.

Considering the green policy requirements of the IMO and the actual needs of the green development of the shipping industry,a competitive game model under two scenarios is built based on the change in ship speed caused by the change in emission reduction strategy.Based on considering the geometric Brownian motion of the total freight scale,this paper uses the theory of real options to explore the timing decision of shipping companies’emission reduction strategy switching.Firstly,we find that stringent green policies,market competition,and shippers’preference for speed do not always motivate shipping companies to shift their emission reduction strategies ahead of time.Secondly,we find that equipment subsidies can always motivate shipping companies to switch green strategies in advance,while operational subsidies can only take effect under certain conditions.Within a certain threshold range,equipment subsidies are always more effective than operating subsidies.Shortening the policy transition period can make the timing of the green strategy switching of shipping companies earlier,but in a specific range,the length of the transition period will not have an impact on the timing of the green strategy switching of shipping companies.Finally,we find that when the total freight volume is large and the growth rate is slow,shipping enterprises will change their emission reduction strategies in advance;Different equipment upgrade environments will have a different impact on the transition time of the emission reduction strategy of shipping enterprises.