Techno-economic viability of islanded green ammonia as a carbon-free energy vector and as a substitute for conventional production

Abstract

Decarbonising ammonia production is an environmental imperative given that it independently accounts for 1.8% of global carbon dioxide emissions and supports the feeding of over 48% of the global population. The recent decline of production costs and its potential as an energy vector warrant investigation of whether green ammonia production is commercially competitive. Considering 534 locations in 70 countries and designing and operating the islanded production process to minimise the levelised cost of ammonia (LCOA) at each, we show the range of achievable LCOA, the cost of process flexibility, the components of LCOA, and therein the scope of LCOA reduction achievable at present and in 2030. These results are benchmarked against ammonia spot prices, cost per GJ of refined fuels and the LCOE of alternative energy storage methods. Currently a LCOA of $473 t⁻¹ is achievable, at the best locations the required process flexibility increases the achievable LCOA by 56%; the electrolyser CAPEX and operation are the most significant costs. By 2030, $310 t⁻¹ is predicted to be achievable with multiple locations below $350 t⁻¹. At $25.4 GJ⁻¹ currently and $16.6 GJ⁻¹ by 2030 prior combustion, this compares favourably against other refined fuels such as kerosene ($8.7–18.3 GJ⁻¹) that do not have the benefit of being carbon-free.