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The Objectives


The overall aim of the Ammonia2-4 project is to demonstrate at full scale both a two-stroke and a four-stroke dual fuel marine engine running on ammonia as main fuel and leading to >80% less GHG emissions (including nitrous oxide emissions), NOx emissions below IMO Tier III regulations and a negligible ammonia slip below 10ppm (Euro 6 compliant).


The proposed four-stroke innovation is a newbuild 10MW engine to be demonstrated in lab conditions closely mimicking real-life operations in ambient conditions.


The proposed two-stroke innovation is a medium-pressure ammonia fuel injection platform that can be retrofitted onto any two-stroke marine engine available in the market today. It will be demonstrated in the project at two stages: a lab demonstration followed by retrofitting onto a real vessel of the alpha customer MSC, which is equipped with a 68MW engine.


By demonstrating both engine types at full scale the project partners are aiming for commercial exploitation of the project results towards more than 90% of the maritime intercontinental transport in terms of gross tonnage, including retrofits and newbuilds to enter the fleet within the next ten years. It is expected that both Ammonia2-4 innovations will lead to an annual reduction of CO2 emitted by deep sea vessels calling at EU ports by 2.3 million tons and reduce the emissions of harmful pollutants such as SOx by 15 tons annually.

The partners believe it is crucial to develop both engine types in parallel (as opposed to consecutive development), since both engine types serve different segments of the market (as will be explained in the following section). By following the ambitious plan to develop both innovations in parallel the partners hope to significantly contribute to reaching the IMO 2050 targets.


The driving force behind the project is a Pan-European consortium consisting of the leading marine equipment manufacturer Wärtsilä, the largest classification society worldwide, DNV, one of the world’s top three container shipowners, MSC, the award-winning naval architecture SME C-Job, and the largest research institute in Italy, CNR. The consortium will work towards closing the current technological, commercial and regulatory gap between insights on the feasibility of burning ammonia in small engines and the actual proof that a large oceangoing vessel can be powered by ammonia as the main fuel in a safe, operationally efficient and economical way.



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