Is green ammonia in the south of Spain cost-competitive by 2030?

Synthetic fuels have been gaining industrial relevance as a means to decarbonize hard to abate sectors like heavy transportation. Green ammonia (NH₃) is envisaged as a key energy vector to accomplish this due to its carbon free combustion and ease of transportation and storage. This study assesses the technoeconomic potential of deploying a 2000 metric tons per day green NH₃ plant in Cádiz, Spain, evaluating a wide portfolio of conversion and intermediate storage technologies to produce the chemical commodity using capital cost and performance data projected to the year 2030, as well as location-specific renewable availability profiles. The key technical outcome of this study is that a partial supply of H₂ from biogas steam methane reforming (SMR) can preclude deployment of hazardous on-site H₂ storage to compensate for wind/solar variability. The LCOA of 590.3 €/t attained for the green NH₃ plant represents a cost premium of 41.6 % relative to a blue NH₃ plant at a CO₂ tax of 100 €/t. Cumulative addition of H₂ storage and grid connectivity next to SMR can reduce costs to 550.4 and 510.6 €/t, respectively, albeit with added risks related to H₂ safety and electricity market exposure. Although simplifying optimization model assumptions, such as optimized investment and dispatch based on one representative year with perfect foresight of wind/solar availability, render these numbers optimistic, results suggest that medium-term subsidized deployment of green NH₃ to diversify the local fertilizer market may be feasible. However, the cost premium of green NH₃ is approximately 160 % relative to liquefied natural gas (LNG), illustrating that alternative decarbonization avenues should be pursued for energy applications.