## 5 Overview of Policy, Technology, and Stakeholder Collaboration
### Technology Overview
[42] employ multi-criteria decision analysis (MCDA) frameworks to critically assess the viability of alternative fuels, underscoring that no singular option meets all operational and economic criteria perfectly. While LNG and methanol-based fuels currently hold higher commercial attractiveness due to their cost efficiency, renewable hydrogen and ammonia exhibit substantial environmental benefits, particularly favored by regulatory authorities emphasizing stringent emission controls. Authors [56] have further highlighted hydrogen's potential for international shipping, emphasizing its superior feasibility due to comparatively lower production scaling requirements, despite technological challenges related to storage. The study illustrates that cryogenic hydrogen storage, despite volumetric limitations, remains viable for larger vessels through strategic storage optimization. Beyond fuel selection, technological innovations enhancing energy efficiency are pivotal. Scholars [52] have explored the adoption of waste heat recovery (WHR) systems, demonstrating their potential to achieve fuel savings ranging from 5% to 15%. This technological advancement not only significantly reduces environmental impacts, but also enhances economic viability by reducing fuel consumption and improving operational efficiency. Complementing this, ref. [58] provide a comprehensive analysis of energy and exergy flows aboard cruise vessels, revealing critical inefficiencies in propulsion and auxiliary energy systems. Their work highlights the need for integrated measurement and modeling techniques to accurately capture energy behaviors, thus informing targeted technology investments. In conclusion, a robust technological overview of GSC underscores the necessity of integrating sustainable fuel alternatives, optimized energy management technologies, and comprehensive operational practices. Strategic technological investment decisions, informed by rigorous analyses, are vital for advancing maritime decarbonization effectively, aligning industry practices with long-term environmental and economic sustainability goals. Table 9 categorizes a list of technology adaptations regarding GSC development within the initiation phase. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Technology Adaptation Name** & **Technology Adaptation Definition** & **References** \\ \hline \multirow{6}{*}{Zero-Carbon Synthetic Fuels} & Adoption of hydrogen and ammonia as & \\  & zero-carbon synthetic fuels for maritime & \\  & transport, primarily for domestic and short-sea & \\  & shipping, characterized by high energy density & \\  & by mass and favorable environmental profiles & \\  & despite storage and infrastructure challenges. & \\ \hline \multirow{6}{*}{Biofuel Hybrid Configurations} & Utilization of biofuels blended with & \\  & conventional fuels, offering commercial & \\  & attractiveness due to emission reductions, & \\  & despite challenges like feedstock availability, & \\  & high production costs, and & \\  & compatibility issues. & \\ \hline \multirow{6}{*}{Waste Heat Recovery (WHR) Systems} & Installation of WHR systems onboard vessels, & \\  & capable of recovering and converting waste & \\  & heat into usable energy, achieving realistic fuel & \\  & savings between 5% and 15%, thus & \\  & significantly reducing both environmental & \\  & impacts and operational costs. & \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Technology adaptation regarding GSC development within the imitation phase. Green shipping corridors (GSCs) are currently in the initiation stage, where the focus is on stakeholder alignment, initial feasibility, and governance structures [11]. The adoption of zero-carbon synthetic fuels, biofuel hybrids, and waste heat recovery systems offers tangible pathways to reduce emissions and optimize operational efficiency. These adaptations, combined with rigorous energy and exergy analyses, can inform a phased roadmap, guiding future expansions of GSC initiatives.