Ammonia as marine fuel
Over 90% of world trade is carried across the world’s oceans by some 90,000 marine vessels. International shipping is the backbone of the global economy but also a major source of emissions.
If shipping were a country, it would be the 6th largest emitter of CO2.
A typical ocean liner requires 40 to 60 megawatts, roughly the same power consumption as a town of about 10,000 homes.
Global shipping is responsible for about 3% of worldwide greenhouse gas emissions.
The International Maritime Organization (IMO) has committed to reducing greenhouse gas emissions from international shipping by at least 50% by 2050 (compared to 2008 emissions), with a strong emphasis on reaching zero emissions.
Some of the required reduction in emissions can be achieved immediately using technical and operational energy-efficiency measures.
However, historically, oil-based fuels have met more than 99% of the total energy demand for international shipping. Efficiency alone will not be sufficient: we need to explore a mix of electro-fuels, alternative fuels and electricity made from renewable energy, biofuels, biogas and ammonia. No single solution fits all. Different solutions suit different vessel types based on size, power and range requirements.
Ammonia is one of the most promising carbon-free alternative fuels. Ammonia can be used by both internal combustion engines and fuel cells, offering potential for retrofits of ships that use internal combustion engines. Its use as a fuel will almost eliminate particulate matter and black carbon emissions, and CO2 if produced using renewables.
“We have to eliminate greenhouse gas. Ammonia is the most advantageous solution.”
Yokoyama Tsutomu
Senior General Manager, NYK Line Green Business Group
Why ammonia?
Zero-carbon
Ammonia’s key advantage is its status as a zero-carbon fuel when produced renewably, enabling ships to eliminate CO2 emissions.
Availability
Ammonia storage
As a commonly traded commodity, ammonia also benefits from well-developed storage infrastructure and a worldwide terminal network.
Established procedures
Since ammonia is transported as cargo, there are established safe handling procedures in place.
Energy density
Ammonia has an energy density by volume almost 30 per cent higher than liquid hydrogen and it is easier to distribute.
Developing technology
Internal combustion engines which consume ammonia directly are closer to at-scale development than other solutions for alternative fuels. MAN B&W, one of the largest marine engine manufacturers, claims that more than 3,000 existing MAN engines can be modified into ammonia engines.
“We like to think of ammonia as the next iteration of LNG – a low-emission fuel with safety challenges, but enormous decarbonisation potential. By combining the right questions with the right tests, we can help de-risk ammonia, enabling our marine clients to benefit from this much-needed zero-carbon fuel.”
Laurent Leblanc
Bureau Veritas Senior Vice- President, Technical & Operations
Early adopters
Currently there are about 200 gas tankers that can take ammonia as cargo and typically 40 of them are deployed with ammonia cargo at any point in time. Vessels like these could be ideal because they already have the fuel as cargo and crews with experience in handling ammonia.