Ferries Spew More Sulphur Pollution Than Cars in Major EU Port Cities
A ferry approaches Marseille, one of Europe's 15 biggest port cities, where 13 are choked more by sulphur oxides from ferries than from road vehicles. This striking image underscores a critical environmental issue revealed in a new analysis.
Key Findings on Sulphur Emissions
Fume-belching ferries are a significant source of sulphur pollution, surpassing car emissions in several EU capitals. According to data shared exclusively with the Guardian, Dublin, Helsinki, Stockholm, and Tallinn are among the 13 port cities where ferries emit more sulphur oxides (SOx) than road vehicles. Europe's ageing fleet of nearly 2,000 ferries represents a large but often overlooked contributor to foul air in coastal urban areas.
Emissions of sulphurous oxides, toxic gases with odors reminiscent of burnt matches and rotten eggs, react to form tiny particles. These particles penetrate the lungs, enter the bloodstream, and can damage organs throughout the body, posing serious health risks.
Broader Impact Beyond Capitals
The analysis from Transport & Environment (T&E), a clean transport advocacy group, also identified ferries as bigger polluters than cars in Athens and Rome. These cities were not included in the ranking because their ports are considered separate entities. Additionally, Valletta, the small capital of Malta, faces similar issues. Major non-capital cities on the list include Barcelona, Marseille, Rotterdam, and Valencia, highlighting the widespread nature of this problem.
"Ferries should connect communities, not pollute them," emphasized Felix Klann, a shipping policy analyst at T&E and lead author of the report. He pointed out that ferries in Europe spend most of their time within five nautical miles of densely populated ports, making them prime candidates for electrification.
Potential for Electrification
Unlike larger ocean-crossing vessels, many ferries could operate on electricity instead of relying on dirty fuels or expensive synthetic alternatives. The analysis found it would have been "technically feasible and cost-effective" to electrify 20% of Europe's ferries by 2025, with this share rising to 43% by 2030 as battery technology advances and prices decrease.
"Too many ferries are burning polluting fossil fuels, pumping toxic air into Europe's port cities," Klann stated. "Electrifying them could dramatically cut emissions and bring a breath of fresh air to millions of people."
Methodology and Regulatory Context
Analysts modeled air pollution in Europe's 100 busiest ferry ports using methods from an International Maritime Organisation (IMO) study. They compared SOx emissions with those from cars based on vehicle registration data within city limits. The study accounted for emission controls in regions like the North Sea, Baltic Sea, and the Mediterranean (starting in 2025), which limit sulphur content in ship fuel to 0.1% of mass—five times lower than IMO requirements.
These restrictions have contributed to a 70% drop in sulphur emissions since 2014, according to the European Environment Agency. However, the report identified requirements for charging infrastructure as the main barrier to adoption, noting that most ports would need only small chargers below 5MW.
Industry Perspectives and Challenges
Sotiris Raptis, secretary-general of the European Community Shipowners' Association, acknowledged that the EU has introduced ambitious policies to support electrification, including a mandate for passenger and container ships to use electricity in ports by 2030. However, he stressed that "enormous" investments are necessary to finance the energy transition in shipping. "What we are missing is investment in clean fuels, energy, and infrastructure in ports to support electrification," he added.
Responses from port authorities varied. The Port of Dublin did not comment, while Ingrid Hansson, spokesperson for the Ports of Stockholm, noted that most customers operate well below sulphur thresholds and have used onshore power since the 1980s, reducing emissions significantly. Ellen Kaasik, environmental manager at the Port of Tallinn, reported investments in onshore power and auto-mooring systems, with plans for electric or hybrid ferries on the busy Tallinn-Helsinki route by 2026.
Andreas Slotte, head of sustainability at the Port of Helsinki, emphasized the need for firm commitments and early cooperation from shipping companies to plan charging infrastructure effectively. "Charging infrastructure cannot be planned and built in a vacuum," he said, highlighting the challenges in transitioning to cleaner ferry operations.
