Decarbonization of maritime shipping: trends, regulatory instruments, alternative fuels, and challenges in achieving net-zero emissions

Despite efforts to optimize ships and operations, absolute greenhouse gas emissions in maritime shipping continue to rise, reaching 121 % of the 2008 level by 2024 due to the growth in global trade and fleet tonnage. The industry's dynamics are driven by macroeconomic and market factors, not solely environmental initiatives. The article analyzes emission trends over the past 20 years and evaluates the economic feasibility and technical readiness implementation of alternative fuels (methanol, ammonia, hydrogen, biofuels) up to 2040. It examines current and prospective regulatory mechanisms, including the IMO strategy for net-zero emissions by 2050 with interim targets for 2030 and 2040, as well as EU regional measures (EU ETS, FuelEU Maritime). Realistic transitional solutions are identified, such as LNG combined with energy efficiency technologies (EET) and onboard carbon capture (OCCS), along with long-term prospects for nuclear energy. Systemic risks and barriers are formulated, including limited availability of low-carbon fuels, rising operational costs (up to $45,000 per day for ships in the EU by 2035), and shipbuilding capacity shortages. Prevailing market dynamics show a lack of economic benefits from "green" fuels due to high costs and infrastructure constraints. Regulatory measures act as additional trade barriers, shifting costs to end consumers. The industry faces a gap between ambitious goals and real capabilities; without synchronizing policy, technology, and capital, achieving net-zero by 2050 remains questionable. The most likely scenario is widespread biofuels, in particular bio-LNG use as a transitional fuel with gradual nuclear implementation in the 2030s.

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