Transitions for ship propulsion to 2050: The AHOY combined qualitative and quantitative scenarios

This paper combines stakeholder assessments of potential scenarios for radical decarbonisation in shipping with scenario simulations with the MATISSE-SHIP model. It advances previous scenario work in low carbon shipping by combining qualitative and quantitative analysis in a ‘reality’ check of transitions scenarios with stakeholders. Stakeholders identified the critical factors covering society, technology, economics, environmental and legislation/policy. The MATISSE-SHIP model applied these factors and assumptions to model the decision process for shipowners in ordering new ships and propulsion technologies. Four scenarios were developed. With strong climate policy, technological growth with power to liquid/gas (PtL/PtG) fuels (e.g. ammonia) and wind technologies come to dominate. In business as usual, continuing emphasis on local air emissions results in the growth of LNG. Weak policies lead to severe impacts of climate change in the medium term. Eventually, cost savings from wind systems and technology development enable alternative fuel technologies to start to develop. If society moves towards sustainable lifestyles, very strong climate mitigation policies lead to a rapid substitution of fossil fuels by PtL/PtG and, in the tanker and bulker sectors, wind.