“The era of maritime transportation is far from over,” may experts declare about the sector that has literally propelled global trade for centuries. From the daring caravels that once crossed unknown seas guided by nothing but human skill, to today’s colossal renewable-powered megaships carrying thousands of containers, shipping has continuously changed itself to keep pace with world’s ever-growing trade. Remarkably, seaborne transportation remains the most energy-efficient method of moving goods globally: a single modern container ship can transport the equivalent of thousands of truckloads while emitting far less CO₂ per ton-kilometre.
Two decades ago, the shipping sector alone accounted for 2.7% of global carbon emissions – roughly 850 million tonnes of CO₂ – generated by a fleet of 38,000 fossil-fuel-powered vessels, across bulk carriers, tankers, general cargo and container ships. Today, the global fleet has nearly tripled, reaching around 112,500 ships, yet total emissions have grown by only about one-third, to an estimated 1.12 billion tonnes of CO₂, and representing approximately 3% of global emissions. The difference in proportions between fleet growth and respective carbon emissions reflect the direct impact of the International Maritime Organization (IMO) net-zero Greenhouse Gas (GHG) strategy launched in 2018, forcing leading carriers to adopt fuel alternatives to reduce environmental impact. The project aims full achievement by 2050.
It’s evident that meaningful changes can only be achieved by robust regulatory frames and massive investments. Supporting IMO’s net-zero GHG, the EU Emissions Trade System sets clear limits on carbon emissions across the entire supply chain, allocating fixed allowances that decrease annually to varied sectors such as power plants, industrial facilities, aviation and shipping. CO₂ emissions become credit units and are linked to a cost. The system incentivizes companies to invest gradually in clean technologies, improve energy efficiency, and adopt low-carbon fuels, driving the industry toward a more sustainable future. Similarly, the US Inflation Reduction Act offers significant financial incentives for the production of green hydrogen, one of the main sustainable fuels maritime sector has been seeking to adopt on larger scales.
These initiatives pave the way for even more ambitious projects, such as the Green Shipping Challenge launched at COP27, which introduced the concept of green shipping corridors. These corridors are designated maritime routes equipped with the full infrastructure needed to support zero or low-carbon shipping, from the production and supply of sustainable fuels to the operation of vessels. Early examples are already taking shape in the trans-Pacific and Northern European corridors, where ports, fuel suppliers, and shipping lines work towards the same goal of resulting in a low-emission supply chain.
As a matter of fact, the steady shift from conventional fossil fuels toward greener alternatives such as LNG, ammonia, e-methanol, and hydrogen has accelerated to a significant pace. In the first half of 2025, 151 vessels powered by non-fossil fuels were ordered to shipyards, representing 19.8 million gross tonnes — a 78% increase in tonnage compared to the same period in 2024. The race for larger environmentally friendly ships has catalysed important projects, including the world’s largest dedicated ammonia carrier fleet, Bahri, the Saudi National Shipping Company. Trought massive investments, the new carrier is building eight Very Large Ammonia Carriers (VLACs), each one roughly twice the size of existing ammonia-propelled vessels, marking a bold step toward scalable decarbonization.
Container carriers are also adapting to evolving market expectations. Many leading shipping companies now allow clients to choose to offset the carbon emissions associated with their shipments, enabling customers to take responsibility for their own environmental impact. In fact, a growing sector has emerged around the trade of carbon credits and investments in environmental and social initiatives, all designed to generate measurable positive effects on the global carbon footprint.
In conclusion, as global trade expands and fleets continue to grow, the maritime industry demonstrates both resilience and innovation, gradually embracing more sustainable practices. Regulatory measures promoting renewable energy use mark a crucial first step toward decarbonizing the entire supply chain. Initiatives like green shipping corridors, alternative fuels, and carbon offset programs highlight the sector’s commitment to reducing environmental impact while maintaining efficiency. The sea remains not just the world’s essential highway for commerce but also a testing ground for some of the most ambitious decarbonization strategies of our era, charting a course toward a greener future.
