Long-term expansion planning of power systems considering renewable ammonia production under different scenarios for the year 2060

Abstract

Climate change is a major global challenge, and renewable hydrogen is key to decarbonizing multiple sectors. However, due to hydrogen transport and storage challenges, ammonia is a viable alternative. The ammonia production process is constrained by some fixed technical factors, which affect system optimization. This work proposes a long-term expansion planning model that integrates renewable hydrogen and ammonia production by 2060. The model optimizes the renewable ammonia plant sizing, considering technical constraints such as load ramping, minimum operating levels, and demand scenarios. The results show that decreasing the minimum-load operational level to 25 % of the nominal capacity of the power-to-ammonia plant significantly reduces both curtailment and CO2 emissions. More temporally-constrained ammonia demand compliance alters the power generation mix, increasing investment in solar energy, but also incorporating geothermal and natural gas power generation. Additionally, the levelized cost of ammonia (LCOA) is evaluated, showing that more operational flexibility in the ammonia production process can significantly reduce the costs.