Greenhouse gas emissions from shipping make up roughly 2.5% of the world’s total, making the ocean freight sector a heavy contributor to the looming environmental crisis. And, unless something is done, as international trade grows this number is only likely to rise.
With numerous countries around the world bringing in carbon border taxes and other taxes on pollutants, this is becoming a financial issue as well as a social one.
Innovations and new technologies are increasingly seen as the way to reduce the shipping industry, and by extension trade’s, carbon footprint.
1. Scrubbing and carbon capture
What’s the idea? One bold idea is to have ships act as a form of carbon-capture, removing carbon dioxide from the atmosphere as vessels traverse open seas and carry cargo.
It has the benefit of relying on pre-existing processes, as land-based carbon capture is a recognised technology, and shipping firms are experimenting with moving the process onto ocean-side vessels.
All shipping segments – including large natural gas carriers, chemical tankers and more specialised vessels – are reported to be examining this.
Recently Admore, a US shipper, announced plans to install carbon-capture tech on board six vessels over the course of the year.
What’s stopping it? Depending on at what stage in the combustion process the capture would occur, shippers face increased costs and difficulties. Issues such as storing the carbon removed from fuels and maintaining it at a precise temperature aboard ship, where space is at a premium, have yet to be solved.
Another drawback is that the process of carbon removal itself can be very energy consuming, although with improved technology this could be brought down
Other options? A related technology, known as “ocean scrubbing”, looks to remove carbon dioxide from the ocean, rather than the air. As the ocean represents the largest “carbon sink” on the planet, cleaning this is a crucial first step in the fight to achieve Net Zero.
Developed by researchers from Massachusetts Institute of Technology (MIT), the proposed method would remove carbon dioxide and turn acidic water back into alkaline before it is released into the sea.
2. Air bubbles
What’s the idea? Another method of reducing shipping’s emissions is to reduce the amount of fuel expended in the process of moving ships around. Large ships generate a lot of drag when moving through the ocean, which in turn requires them to burn more fuel.
A rapidly developing technology known as “air lubrication” has been gaining increased interest in recent years. The technology relies on bubbles of air to streamline the hull of the ship along the ocean, in effect, lubricating the ship as it travels.
The continuous, thin layer of air reduces drag on the hull and increases fuel efficiency. It also helps reduce noise pollution and reduces so-called ‘bio-fouling’, where invasive plants, animals and other organisms cling to a vessel’s hull and damage the sea’s bio-diversity, and.
Companies such as Silverstream and Armada Technologies have increased their offerings to shipping firms in recent years, with freighters including Mearsk and Grimaldi, and cruise liners such as P&O, Carnival and Costa Cruises amongst the early trialists.
What’s stopping it? The technology is still in development and minor differences in the ship’s hull and the size and speed of the bubbles can reduce the effectiveness of the technology. Many older ships would also require extensive retro-fitting, driving up costs for shippers relying on older fleets.
3. E-Fuels
What’s the idea? The use of more environmentally friendly fuels has been a major source of hope for the shipping industry. This includes the group of energy sources known as ‘e-fuels’.
Fuels such as methanol and ammonia, as well as green hydrogen, are often described as being a key part of the maritime industries move towards net zero. This would see large, ocean-going vessels move away bunker fuels, based largely on petroleum or diesel and responsible for producing harmful sulphur oxides, towards cleaner, less harmful sources.
What’s stopping it? These newer fuels come with several challenges. One major issue is the cost. E-fuels are very much in their infancy, and face the problem of a lack of economy of scale. Another difficulty arises from the production of the fuels, which often use extensive fossil fuels to produce the ‘clean’ fuel in the first place. This introduces a high risk of emissions displacement rather than reduction.
EU, UK and Indian government initiatives have all been announced to grow and regulate green fuels, with the EU voting in October to introduce a 2% mandate for green shipping fuels by 2030.
Other options? Several international ports – including Geelong in Australia, the Dutch ports of Rotterdam and Amsterdam and a planned site in Southern Spain – are exploring how to implement green hydrogen facilities. This is where hydrogen is created using electricity from renewable sources.
4. Biofuels
What’s the idea? A related, but different category of fuels for shipping are biofuels. These are made from biological materials such as cooking oil and encompass everything from biodiesels to bioethanol.
If they are made from recycled materials or waste, they have the potentially to be fully sustainable. Depending on the blend, they are also low in sulphur and carbon dioxide.
One advantage of this is that they are relatively easy to drop in and don’t require any expensive adaptations for existing ships. Refits are largely unnecessary, increasing the cost benefits.
“Ships can operate on 100% biofuel right now, but it depends on the type of biofuel. Most of the demonstration studies that I am aware of have used what we call biodiesel in the United States or FAME (fatty acid methyl esters),” Michael Kass, a researcher of fuel, engines and emissions, told Seatrade Marine.
In December 2022, the Stamford Eagle – a bulk carrier built in 2016 – made a trip from the Netherlands to Norway using biofuels that reportedly reduced carbon emissions for the voyage by 80%.
What’s stopping it? The main problem now is price and scalability. Biofuels are expensive, making the business case for using them difficult. There also remain concerns that high demand coupled with low supply would further push up prices.
Another key issue is ensuring that the source of the biofuels doesn’t add to environmental problems by contributing to deforestation or producing carbon emissions in their creation.
5. Digitisation and green corridors
What’s the idea? Physical technologies are not the only way of tackling shipping’s emissions problem. Regulatory changes, or the move to a more digital form of international trade could offer even more opportunities.
Schemes such as “green trade corridors”, are gradually being developed by national governments and industry around the world.
Developed first out of the Clydebank Declaration, this involves the creation of a zero-emission maritime route between two or more ports, using a combination of targeted investment, financial incentives and changes to regulations.
Two routes already in use – the Asia-Europe container and Australia-Japan iron ore routes – are being studied, with the US-Asia car carrier lane being considered as a case study.
The UK government is currently working on Electronic Trade Documents Bill to allow for freight companies to switch to paper, a concept that is already being embraced by industry.
The Digital Container Shipping Association, an interest group focused on electronic trade documentation, announced last week that nine shippers have committed to fully digitising their bills of lading by 2030, in a move that is expected to save up to $6.5bn in trade growth.
They argue that paper-based processes are time-consuming and environmentally unsustainable, resulting in delays of cargo. Moving to digital bills could save up to 28,000 trees per year, equivalent to around 39 football fields of forest, according to the organisation.
What’s stopping it? Trade digitisation largely relies on proven technology, but faces a number of barriers that have to be solved by both industry and government.
Susan Roe, trade and customs consultant at the Institute of Export & International Trade Academy explains:
“The technology is there, but so remain some concerns and barriers. First, there is no doubt that digitisation is taking place across the world – but at different speeds. Digital trade needs to be all or nothing.
“Second, there is also the issue of who’s role is it to fully implement digital trade across the board - government or industry?
“Third, English and Welsh law still lends importance to physical rather than digital possession of certain trade documents, particularly the bill of lading, one of the oldest in global trade, and one that legally provides document of title to the cargo.”