RTM Tasman vessel, marine operation

Decarbonising the high seas

Finding solutions to shipping’s global carbon emissions



Maritime shipping underpins 90% of world trade. It’s the nexus connecting mining companies and our raw materials with manufacturers, who create and ship products to retailers and consumers, making our modern lives possible.

But it’s also responsible for around one billion tonnes of CO2 emissions annually, accounting for nearly 3% of global carbon emissions. As consumers become ever-more conscious of purchasing low-carbon products, and demand for international goods continues to rise, the global maritime industry faces a significant challenge to quickly decarbonise.

As the largest dry bulk shipper in the world, we’re uniquely positioned to reduce overall maritime emissions. We own 17 ships and charter 230 vessels, moving around 315 million tonnes of raw materials across 2,700 voyages every year.

We’re already making progress. We’ve delivered 30% out of the 40% International Maritime Organization (IMO) targets required by 2030 (from 2008 baseline), and we aim to achieve the full 40% reduction by 2025.

And we’re working harder and smarter than ever before to achieve our company-wide goal of net zero emissions from our operations by 2050.

Improving vessel efficiency

Replacing current fuels with new zero-emissions fuels may seem like the easiest way to reduce maritime emissions. But such fuels aren’t yet available in commercial quantities, making them significantly more expensive and less accessible.

So until they become viable, we can reduce emissions faster by ensuring our ships use less fuel in the first place.

We’ve already reduced the intensity of our fuel use across our owned and time-chartered fleet by 30% from an International Maritime Organization 2008 baseline. We’re achieving this by using more efficient vessels, weather routing and schedule optimisation, which we anticipate will help us exceed the International Maritime Organization’s 2030 targets to achieve a 40% reduction by 2025.

Through to 2024, we’ll also be modifying our owned vessels to further reduce emissions by 10% or more on our owned fleet – applying high-performance paints to ships' hulls to reduce friction, modifying propellers, and integrating swirl ducts that enhance water inflow to the propellers.

To further improve our fleet’s efficiency, we’ve invited and received over 70 submissions from technology companies, research institutions and others to collaborate with us to boost efficiency. We’re partnering with the Maersk Mc-Kinney Moller Center for Zero Carbon Shipping to conduct technical reviews on shortlisted submissions, and will be installing and testing the most promising ones as part of a laboratory concept on two of our owned vessels in 2023. We also intend to openly share our findings, so the broader maritime industry can apply these insights to reduce overall industry emissions.

RTM Tasman vessel, marine operations

Transitioning to transitional fuels

It may still be years before long-term green shipping fuels are commercially viable or accessible. But in the meantime, we’re pursuing “transitional” fuels, which create lower carbon emissions than traditional marine fuels.


We recently signed a 5-year charter contract for nine Newcastlemax dual-fuel vessels, which can operate on both liquefied natural gas (LNG) and conventional marine fuel, and will be delivered from the first half of 2023.

Together with bp, we’ve also started one of the maritime industry’s longest trials of biofuel. Our RTM Tasman vessel, a 205,432 deadweight tonnage bulker that plies the Transatlantic and Atlantic Pacific routes carrying iron ore from Canada, will trial biofuel at 30% blend with very low sulphur fuel oil (VLSFO) for a year.

Neither LNG nor biofuel blends are carbon free. But LNG delivers a 15–20% carbon reduction on marine diesel while eliminating a lot of the particulates associated with traditional fuel consumption. Our biofuel blend offers a 26% reduction, and while procuring sustainable feedstock for biofuels or affordable LNG can be challenging, these fuels remain an important part of the carbon-reducing mix.

Building supply chains to support decarbonisation

While we’re committed to moving quickly to a carbon-free future, we can’t do it alone.

The collective challenge for the industry, across the whole supply chain, is to state ambitions, partner, and provide access to incentives supporting the transition. Prioritisation and private-public partnerships will play an essential role in achieving net-zero shipping.

We’re working towards this in a few different ways. After participating in a joint study framework of ammonia as a maritime fuel – with 34 partners and led by ITOCHU Corporation in 2021 – we’ve partnered with ITOCHU, K-Line, NS United and Nihon Shipyard to develop an ammonia-fuelled vessel design and ammonia supply chain.

We’ve also joined a consortium led by the Global Maritime Forum to study the development of the ammonia powered Australia-East Asia iron ore Green Corridor, one of the largest global shipping routes. In bringing shippers, fuel suppliers, shipping companies, ports and governments to share their perspectives and knowledge, we hope to set clear objectives and a timeline to develop a cost-competitive corridor.

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