How do we achieve sustainable shipping?
Sustainable shipping is about much more than just cutting CO₂ emissions. It is a holistic challenge where climate, the marine environment, safety, operations, and economics are all interconnected. Ships must transport goods efficiently and safely while minimizing emissions and pollution.
Shipping companies must be able to invest in green technologies such as alternative fuels, more energy-efficient engines, and smarter route planning if shipping is to become climate-friendly in the long term, but this requires that the investments be economically viable.
Sustainability is therefore not a single goal, but a complex interplay of many factors. Decisions regarding CO₂ reduction, ship technology, and environmental protection must be considered holistically, so that improvements in one area do not create problems elsewhere. Only this way can shipping develop responsibly and robustly.
What is the problem?
Shipping transports a large portion of the world's goods and is crucial for security of supply. Shipping accounts for about 2–3 percent of global CO₂ emissions, which are expected to rise as global trade grows. The climate and marine environment are affected, and geopolitical tensions set the agenda and may delay the transition to more sustainable solutions.
Specific situations, such as having to sail around conflict zones or when ships block key shipping routes, lead to longer voyages, higher fuel consumption, and increased CO₂ emissions.
Disagreements within the International Maritime Organization regarding CO₂ taxes on shipping—with the goal of introducing an international climate tax starting in 2029—also stand in the way of continued sustainable development. This makes the transition even more complicated.
What are the biggest challenges?
Ships last for many years and are built for specific purposes, making it expensive and complicated to modify them. This means it takes a long time before old ships are replaced and new, more sustainable ships can be built, while investments, fuel, infrastructure, and regulations are still being developed.
International standards and political agreements are crucial but complex, as decisions are influenced by factors such as the U.S. and geopolitics. Denmark is a strong maritime nation, with several shipping companies serving as first movers, but to make a real difference, we depend on close cooperation both in Europe and globally.
How far have we come?
There is greater focus on sustainable shipping today. Compared to 10 years ago, there has been clear progress, but the many different technologies make it difficult to measure overall development.
Much wastewater is now discharged at ports instead of directly into the sea, and ballast water is treated with UV to prevent the spread of invasive species. New ship paints and low-vibration hulls prevent algae and mussels from attaching without reducing efficiency or creating noise, and ships plan their routes to avoid vulnerable natural areas.
Today, development is driven by the EU and the UN, which set frameworks and ambitions through legislative packages and research programs such as Euronet, while companies, researchers, and authorities collaborate on solutions that increase efficiency and reduce environmental impact.
Name one thing that can make the biggest difference over the next 10 years.
Collaboration—both across research fields and among stakeholders in the maritime sector.
The green shipping of the future requires close collaboration between research, industry, and authorities on an international level. New technologies must be scalable, the infrastructure must be in place, and the fuel supply must be secure—both in Denmark and around the world. Countries must collaborate on regulations, standards, and port infrastructure so that solutions can be used effectively across borders and routes.
No single solution covers everything, so we must focus on a mix of fuels and technologies, depending on ship type and route. Some ships can use batteries for short routes, while others use ammonia, methanol, or bio-oil for longer voyages.
When will we have sustainable shipping?
We can only say that shipping is sustainable when it no longer negatively impacts the climate and the environment. This requires high ambitions, research, testing, and responsible implementation, because new technologies can have unforeseen negative consequences, such as methane emissions, which contribute significantly to global warming. New green technologies can also have negative safety implications.
Although total sustainability may not be realistic, shipping can still be optimized. New solutions such as CO₂ capture may come into play, but common standards and clear measurement methods are crucial to ensuring that progress is real and holistic. There is still a long way to go, but developments are moving in the right direction.
