The International Maritime Organization (IMO) and European Union (EU) have set targets to reduce greenhouse gas (GHG) emissions. Focusing on ships above 5000 GT, their measures exclude several ship types, such as fishing vessels, offshore ships, and yachts. However, smaller ships generate 15–20% of the total GHG emissions. Multiple potential fuel alternatives are already in use or have been investigated to minimize carbon emissions for coastal ferries. This study evaluates the possibility of using alternative fuels for small ferries by seven different parameters: technical readiness, presence of regulations, GHG emission reduction effectiveness (with two different criteria), capital expenditure (Capex), operating expenditure (Opex), and ice navigation ability. The assessment is based on an evaluation of state-of-the-art literature as well as second-hand statistics and press releases. The study also reports the most recent implementations in each alternative technology area. As a result, it was found that although there are several measures with high potential for the future, the most feasible fuel alternatives for coastal ferries would be fully electric or diesel-electric hybrid solutions.

The maritime sector aims to achieve carbon neutrality by 2050. Consequently, shipping companies are investigating efficient and optimal ways to minimize greenhouse gas emissions. One of these measures includes vessels that operate on alternative non-carbon fuels. In this study, we compared a diesel-fuelled catamaran’s greenhouse gas (GHG) emissions and its fully electric sister vessel, which operates on the same line. This study showed that the GHG emissions of the electric vessel were only 25% of those of its diesel-powered sister vessel. However, this figure highly depends on the source of electricity in the operating country. In this case, the energy cost of the fully electric vessel was 31% cheaper than the cost of diesel energy and the payback time without possible subsidy for replacing a diesel ferry with an electric one would be 17 years and 6 months. We also showed that the additional energy from solar panels sufficiently covers several application options for consumers even in winter, when there is low solar energy production. This study brings more insight into the academic literature on decreasing maritime CO₂ emissions from city water traffic. Regarding its managerial implications, our study findings can be used when shipping companies evaluate options for reducing their emissions. The results of this study show that using fully electric vessels has major benefits not only concerning carbon emissions but also financially.

The FuelEU Maritime Regulation, part of the European Union’s (EU’s) Fit for 55 initiative, aims to achieve significant reductions in greenhouse gas (GHG) emissions within the maritime sector. This study assesses the feasibility of alternative fuels for the Estonian pilot fleet using a Well-to-Wake (WtW) life cycle assessment (LCA) methodology. Operational data from 18 vessels, sourced from the Estonian State Fleet’s records, were analyzed, including technical specifications, fuel consumption patterns, and operational scenarios. The study focused on marine diesel oil (MDO), biomethane, hydrogen, biodiesel, ammonia, and hydrotreated vegetable oil (HVO), each presenting distinct trade-offs. Biomethane achieved a 59% GHG emissions reduction but required a volumetric storage capacity up to 353% higher compared to MDO. Biodiesel reduced GHG emissions by 41.2%, offering moderate compatibility with existing systems while requiring up to 23% larger storage volumes. HVO demonstrated a 43.6% emissions reduction with seamless integration into existing marine engines. Ammonia showed strong potential for long-term decarbonization, but its adoption is hindered by low energy density and complex storage requirements. This research underscores the importance of a holistic evaluation of alternative fuels, taking into account technical, economic, and environmental factors specific to regional and operational contexts. The findings offer a quantitative basis for policymakers and maritime stakeholders to develop effective decarbonization strategies for the Baltic Sea region.

The need to decarbonise and reduce pollutant emissions from maritime transport is facilitating the studies of ground effect vehicles. Technical development in recent decade concerning unmanned flights in drones has supported this development. These vehicles could have much higher speed than sea vessels and they are estimated to be less costly compared to air transport. Unmanned operations without passengers enable wider range of transport connections (even in difficult conditions). In this research we analyse prototype vehicle called Airship and its possible use in different routes of intra Canary Islands’ transport. We suggest the most lucrative routes and cargo groups. Initial cost and revenue considerations are made over the life-cycle of Airship. As a result, we can point that there are three main factors determine the success of the transport operations. They are: the number of journeys per day, business days operating per year and freight price.