An Evaluation of Suitable Methods to Deal with Deep Uncertainty Caused by the Energy Transition in Ship Design

Abstract

The maritime industry is transitioning toward zero emission. To ensure compliance with future emission reduction regulations, many different alternative fuels and technology options are being investigated and evaluated. However, as these are ongoing developments, this results in varying and changing data on the performance and requirements of options. On top of that, while regulatory ambitions are aiming for increasingly larger reductions of Green House Gases (GHG) and other harmful substances, the level and details of the future regulations are unknown and subject to ongoing scientific and societal discussions. The level of uncertainty regarding regulation and technology for the energy transition can be defined as being deeply uncertain, which means uncertainty cannot be ordered in terms of possibility or occurrence. Although uncertainty is not uncommon in ship design, ship owners and designers are faced with an unprecedented level of uncertainty and require new methods to deal with this. This paper therefore investigates and compares several methods that could be used to increase the feasibility of future energy carriers in the design process, while accounting for the uncertainty in regulation and technical details of alternative fuels. Three promising methods were identified in a literature research: Firstly, Dynamic Adaptive Policy Pathways (DAPP) evaluates alternative options and develops possible pathways to compliance. Secondly, Responsive Systems Comparison (RSC) determines performance of a design in established scenarios (epoch), also allowing evaluation including retrofit (changeability). Thirdly, Robust Decision making (RDM) explores the effect of uncertainties on a pre-specified design and analyses its vulnerability. Within this paper, a first comparison is carried out by applying each method to a general cargo ship case. The goal is to better understand the usability and potential of each method for the energy transition in shipping. Each of the researched methods was shown to allow for different insights in option performance in uncertain conditions during the early design stage. With DAPP providing a global, but clear overview of the possible future pathways toward emission reduction compliance of the design, RSC giving a more detailed insight of technology options in specific scenarios (including evaluation of changeability in a scenario) and RDM allowing a more in depth research of the alternative fuel’s parameters and the circumstances under which these might comply. With each method demonstrating its own strength, future research will develop more realistic and complex designs and processes to be applied to a combination of the beneficial aspects of two or more methods.