Abstract
Fossil fuels are no longer accepted as the sole energy source with their environmental impacts and fluctuating price. Green hydrogen is considered a potential candidate for fossil fuel soon—however, hydrogen is facing the challenges of storage and transportation. Green ammonia, with its ease of transport and storage, is another promising alternative. Decarbonizing ammonia production is an environmental press toward achieving net-zero emissions by 2050. This work summarizes the up-to-date progress in the green ammonia production methods. An assessment of the different production methods was conducted to highlight the merits and constraints of each approach.
Moreover, the promising applications of green ammonia in the energy sectors were discussed. The various barriers, i.e., technical, economic, environmental, and regulations and policies, facing the widespread of green ammonia were also discussed. Finally, the contribution of green ammonia in achieving the different sustainable development goals was elaborated, focusing on the contribution of green ammonia in achieving climate change (SDG 13), clean energy (SDG 7), and other sustainability-related goals. Low efficiencies, high cost, and negative environmental impacts are the common challenges of the various production methods. The progress in green ammonia is essential for achieving SDG2, “Zero hunger”. SDG3 “healthy life and well-being” and SDG13 “Climate action”, will be achieved by eliminating 3.85 kg CO2-eq/kg NH3 emitted from conventional ammonia-based processes.
Ease storing of green ammonia in liquid form (at 9 bar or cooling to −33°); makes it the best green energy source, i.e., achieving SDG7 “green and affordable energy”. By 2050, green ammonia is expected to represent 99 % of marine fuel, thus contributing to SDG9 “Industry and Infrastructure”. Moreover, green ammonia production will save 35.2 GJ of natural gas, thus achieving SDG12 “Responsible consumption/production”.