The Brooklyn Navy Yard鈥檚 sprawling industrial complex once employed 70,000 workers to build US battleships and aircraft carriers during the second world war. Almost 80 years later, it has become home to a New York City start-up with a very different maritime mission 鈥� harnessing ammonia as a low-carbon fuel for the global shipping industry.
The start-up Amogy has already shown how its ammonia-powered technology can work in a flying drone, a John Deere tractor and most recently a semi-truck. But the company thinks its best chance for success is in shipping, which accounts for 3 per cent of the world鈥檚 carbon emissions, and so it is currently converting a tugboat to run on ammonia. A successful waterborne demonstration later this year would set a course for the first commercial offerings to follow in 2024.
鈥淭he tugboat is important in that this is really the first ammonia-powered vessel,鈥� says , CEO and co-founder of Amogy. 鈥淏ut there are so many more larger vessels that we have to convert, because they are probably the bigger problems when it comes to decarbonisation.鈥�
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Most ships and trucks currently run on fossil fuels that emit greenhouse gases and other pollutants. One alternative involves converting vehicles to hydrogen power that would only give off water emissions. But hydrogen gas needs to be compressed and liquefied at -253掳C (-423掳F) for storage and transportation.
Ammonia could serve as an alternative hydrogen-bearing fuel that is more easily stored and transported in a stable liquid form at room temperature. 鈥淚f you really need a lot of energy on board a ship, or if you鈥檙e trying to have a fuelling station that鈥檚 far away from your production centre, it鈥檚 easier to have tanker trucks with ammonia in them than hydrogen,鈥� says at the Clean Air Task Force, an international non-profit based in Boston.
Hydrogen can be extracted by heating ammonia to high temperatures, which is a process that comes with its own energy cost. This is where Amogy鈥檚 technology comes in. To make ammonia power more viable, the company has developed what it describes as a more efficient and miniaturised 鈥渁mmonia cracking鈥� method that can chemically extract hydrogen from ammonia at a lower temperature. The company uses a proprietary catalyst to speed up the ammonia cracking process inside a chemical reactor that feeds into a hydrogen fuel cell.
鈥淲hat Amogy was able to bring to the table is that by having better catalytic technologies 鈥� what I鈥檓 assuming because this is all proprietary 鈥� they were able to miniaturise their ammonia cracking units and put them on board vehicles,鈥� says , a chemist at Saint Mary鈥檚 College of California.
In July 2021, Amogy first showed that its system could supply 5 kilowatts of power to a drone. By comparison, a standard ammonia cracking system for extracting that amount of hydrogen power is usually the size of a large shipping container. The drone demonstration helped Amogy land its first investments from companies such as Amazon.
It also paved the way for a 100-kilowatt tractor demonstration in May 2022, followed by a 300-kilowatt semi-truck demonstration in January 2023. The truck is able to carry 900 kilowatt hours of stored electric energy after filling the ammonia tank within 7 to 8 minutes, which is comparable in power to battery-powered trucks such as the that requires 30 minutes of charging to recover 70 per cent of its range capacity.
Amogy is now working toward demonstrating a 1-megawatt system in the tugboat 鈥� three times more power than the semi-truck demonstration. In March 2023, Amogy announced that it had raised an additional $139 million from investors to support a power-pack manufacturing facility in Houston, Texas.
Many countries already have pipelines and port facilities for handling ammonia that is produced industrially as fertiliser for agriculture. The US alone has more than 5000 kilometres of ammonia pipelines compared with 2500 kilometres of pipeline for transporting hydrogen 鈥� though it will need more to support ammonia-powered vehicles.
Another challenge is that ammonia still 鈥渉as a carbon footprint associated with the production鈥� because the standard industrial process uses natural gas, says at the Clean Air Task Force. Low-carbon ammonia production would require use of carbon capture.
Cleaner alternative methods could ideally use electricity from renewable power sources to split water into hydrogen for conversion to ammonia, says Wakim. But this production method also has higher costs, which means governments will need to provide carbon regulations and economic incentives to encourage adoption of this approach.
All these factors are part of the reason why Amogy is looking for its first customers in Scandinavian countries that combine high carbon taxes and stringent regulations with a strong ammonia infrastructure. 鈥淥nce that goes successfully, we will be able to expand globally,鈥� says Woo.
