Techno-Economic and Environmental Risk Analysis of Green and Blue Ammonia as Sustainable Energy Carriers

Replacement of fossil fuels with low-carbon hydrogen carriers is an important step towards achieving climate goals at the global scale, particularly in difficult-to-abate industries like shipping, fertilizers, and industrial heat. Ammonia (NH 3) is a potential carbon-free carrier because of its high hydrogen concentration and the ability to easily transport it and also because it can be used with current infrastructure. This work is viewed as an integrated comparison between green ammonia (renewable-valved electrolysis) and blue ammonia (natural gas with carbon capture and storage) in terms of techno-economic feasibility, lifecycle emissions, and transition risks.It is based on a component of mixed-method technological-economic analysis (TEA), lifecycle analysis (LCA), and probabilistic risk analysis. Findings demonstrate that blue ammonia is able to achieve up to 30 percent of cost savings relative to production with cogeneration assistance, though the climate advantage relies heavily on reducing methane leakages to less than 0.2 percent. Green ammonia is better long-term sustainable but is still not developed due to high capital formation cost (around 1.2 BUSD/GW) and technological immaturity. Shipping is the most cost-effective method of transport over 180 km.Uncertainties in the policy, the vulnerability of the supply chain, and safety risks have also been identified by the Monte Carlo risk analysis as some of the most significant setbacks. The results offer practical recommendations on how to scale up low-carbon ammonia and can speed up the clean energy transition.