光伏驱动电解水制氢系统用于可持续氨生产的性能分析：季节性与区域性评估

Abstract Green ammonia is a cleaner alternative of traditional processes that are energy-intensive and relies on fossil fuels. However, effectively integrating elements such as the photovoltaic system, the electrolyzer, and the ammonia reactor is a challenge that significantly impacts the production cost. The consistent operation of the electrolyzer and ammonia synthesis process are also influenced by the inherent intermittency of renewable energy. In this study, a Transient System Simulation (TRNSYS) model is developed in order to assess the performance of a 24 kW p photovoltaic-driven alkaline electrolyzer system with single-pass Haber-Bosch reactor of 15.55% conversion efficiency in different locations with a particular focus on Tunisia. The model includes a power conditioning unit and variable mode controller and demonstrates stable and efficient operation despite solar fluctuations. The study also establishes a methodical approach to calculate the optimal sizes for hydrogen and nitrogen storages, as well as the reactor load, taking into account the delay period in the ammonia synthesis process. According to the results, Tataouine, Gafsa, and Kasserine in Tunisia exhibit the highest expected NH 3 production potential, with 210.04 kg/kW p , 206.17 kg/kW p , and 205.57 kg/kW p , respectively, benefiting from optimal solar conditions. Globally, Abu Dhabi leads with 216.77 kg/kW p , followed by Chile at 205.22 kg/kW p and Canberra at 202.61 kg/kW p . Conversely, Germany (146.66 kg/kW p ) and Netherlands (144.67 kg/kW p ) show lower expected production. In terms of production costs, Pretoria has the lowest at $494.56/ton·NH 3 , while London has the highest at $834.58/ton·NH 3 Locations like Pretoria, Riyadh, and Abu Dhabi experience payback periods of 9 to 10 years, though all locations still show negative net present values (NPVs) by using low conversion efficiency processes, i.e., in the least favorable scenario, indicating no profitability within the 20-year project lifetime. Sites with lower production, such as London (3.32 ton.NH 3 /year) and Stockholm (3.43 ton.NH 3 /year), face longer payback periods of 12 to 13 years, also with negative NPVs which demonstrate economic difficulties facing green ammonia projects and emphasizing the need for cost reductions or market improvements to enhance profitability and attract investment in this sector.