Three key insights into Exporting Ammonia
Ammonia (NH3) is accepted as one of the most viable means of long-distance transoceanic transport of green H2 molecules. BE&R has undertaken several ammonia-related export and ship bunkering studies. Following are some valuable insights gained from these studies.
Investing too soon and the risk of stranded assets
Drawing analogies to the development of LNG as a marine fuel, BE&R can foresee the same “chicken and egg” scenario, slowing the take-up of ammonia as an industrial and marine fuel. Without a firm market demand, infrastructure suppliers will be reluctant to invest. Without supplier infrastructure, potential end-users will hesitate to invest in the demand side. The current appetite for early uptake of ammonia is also impacted by the uncertainty around the choice of future fuels and the immaturity of the ammonia engine technology.
One option available to infrastructure suppliers is to deploy ammonia-ready LNG infrastructure. For example, Oceania Marine Energy is building an ammonia-ready LNG bunkering vessel. The bunker vessel will operate in the immediately available LNG bunker market while also providing confidence to ammonia producers and ship owners that the relevant infrastructure will be in place to facilitate the development of the ammonia-as-a-fuel market. Designing the vessel to accommodate LNG or ammonia also reduces the risk of the bunker vessel becoming a stranded asset when the market moves to ammonia as a fuel.
Storage and transportation
Should a choice be made to invest in assets compatible with NH3, the following key aspects need to be taken to account:
- NH3 requires around 1.6 times more storage space than LNG for the equivalent energy content. Therefore to meet the same energy demand, a vessel designed to carry either liquid will need to be increased in size to accommodate ammonia
- NH3 has a higher density than LNG; hence the vessel will require more structural reinforcement. This may also equate to increased operating drafts
- Materials compatible with LNG are not all compatible with NH3. For example, NH3 is corrosive to nickel and degrades some elastomer seals
- Standards and guidelines are established for the transportation and bunkering of LNG. Standards and guidelines for NH3 transportation are also established but are still under development for NH3 bunkering and use in ships’ engines
- The toxicity and environmental impacts of NH3 versus LNG require further levels of safety management. Safety management of NH3 is well established in multiproduct gas carriers and export terminals but not for combustion in ships engines and bunkering.
- Gas-fired marine engines that can be converted, at a reasonable cost, to run on NH3 are not yet commercially available but will be in the near future.
Export & import infrastructure
A number of NH3 export infrastructure projects are struggling with selecting a concept with low upfront CAPEX, the ability to scale as the market grows and achieving minimal environmental impact. NH3 export projects are finding that the use of conventional export jetties is prohibitively expensive unless large scale demand is immediately available or an existing terminal can be used. Lessons learnt from the small scale LNG and existing NH3 export industries can be applied to select cost-effective infrastructure that allows a small-to-large scale application. Key aspects the export facility design should consider:
- How quickly will the market mature? This impacts sizing of equipment and scalability considerations
- Proximity to environmentally sensitive areas and population centres
- Leak detection and potential for leak minimisation in design
- Environmental impact through seabed disturbance
- Design of subsea pipelines. NH3 is transported at higher temperatures than LNG and subsequently will not need as expensive insulation or pipe in pipe solutions compared with LNG
- Boil-off gas management of long pipelines when not loading
- Technology risk. For example, weather vanning export solutions requiring the use of swivels qualified for LNG but not yet for NH3
