Ammonia as a marine fuel
The decarbonization of the shipping sectorultimatelyrequiresthe switch to alternative post-fossil fuels. Ammonia has recently received increasing attention as a potential marine fuelthat could drive thisdecarbonization.In the context of a growing hydrogen economy, ammonia is also interesting as the cheapest form in which to transport hydrogen overlong distances and in large volumes.Itis a basic chemical which is globallytraded and produced;it has mainly been used for fertilizer productionto date.However, ammonia has hitherto not beenused as a marine fuel.It isacarbon-free energy-carrier but also toxic.If ammonia were to be used in shipping, it needsto be safe for humans and the (marine) environment. While decarbonizingthe sector, ammonia should not result in higher emissionsor environmental risks.This study assesses whether thesepotential risks and challenges of ammonia have been sufficiently consideredand whether this impactsammonia’s suitability as a future marine fuel.The study summarisesthe state of the artand focuses on ammonia’s impact on marine ecosystems as well asthe environmental impact of combusting ammonia.