Against a backdrop of scientific and climate evidence, significant social and public pressures, and regulatory policies requirements, shipping industry, like any other carbon-intensive critical economic sector, is required to come to terms with the phenomenon of climate change and take steps to effectively decarbonize in line with the ambition of the ratified decarbonization strategies at the international and European level. To do so, shipping companies have to strategically weight the financial and environmental impacts of continuing to operate in a Business As Usual (BAU) scenario against proactively working towards pursuing meaningful GHG emissions reduction efforts through the deployment of alternative fuels. In this context, this master thesis delves into the state of play of decarbonization efforts in the shipping sector, focusing primarily on the EU passenger ferry sector which is intrinsically important to Greece. Through an analysis of the current GHG emissions reductions frameworks for a number of potential alternative fuels, namely HVO biofuel, Grey Methanol and Biomethanol, this thesis endeavors to quantify the annual financial and environmental performance of each fuel use scenario onboard a representative RoPax of the Greek coastal shipping up to CY2050 where there is visibility to the statutory requirements set by the European and international regulations. The findings of this financial and environmental feasibility study indicate that from a strategic point of view all interested stakeholders should start developing their alternative fuel uptake strategies without delay as they will be better-off both in financial and environmental terms if they do so. Therefore, the conclusions of this thesis have great relevance with many stakeholders within the shipping industry and as such can be used variously; ship operators can be supported in their dilemmas of whether it is beneficial to start transitioning towards low-carbon fuels receiving quantitative insights regarding the predicted monetary savings and avoided GHG emissions that can be achieved in each respective alternative fuel use scenario; policymakers can evaluate if the ambition of their set GHG emissions reduction limits are enough; Fuel suppliers can predict potential spikes in market demand for a specific category of low-carbon fuels such as biofuels as they have been notably favored by the current environmental regulatory frameworks in the shipping sector.