In the transition towards a renewable energy-powered industrial sector in the Netherlands, hydrogen plays a pivotal role. The anticipated increase in hydrogen demand by 2030 is projected to exceed the anticipated capacity of domestic green hydrogen production, hindered by the high costs and fluctuations of local renewable electricity generation. To address the growing demand, the consideration of importing more cost-effective green hydrogen is regarded as an appealing option. Storing and transporting hydrogen as green ammonia emerges as a compelling choice for hydrogen importation, given high volumetric hydrogen density of ammonia, coupled with its effective storage and well-established infrastructure. An essential element in the importation of hydrogen through green ammonia lies in the decomposition of green ammonia back into hydrogen. This research evaluates the techno-economic feasibility of hydrogen production using an ammonia cracking process plant in the context of the Netherlands. Two process plant configurations were developed and evaluated on their performance. Both of the plants are set to generate 100 TPD of hydrogen at 50 bar pressure for the Dutch hydrogen grid. The first configuration is designed for the ammonia-to-hydrogen process plant using existing technologies applicable on a large scale by 2030, with a particular focus on the ammonia cracking reactor configuration as the central component. The second configuration is formulated based on the emerging technology of employing the membrane-assisted reactor for ammonia decomposition and is used for comparison with the existing technology configuration in the context of the year 2040. Economic evaluation of both configurations indicates that the Levelized Cost of Hydrogen (LCOH) derived from green ammonia is primarily driven by the market price of green ammonia. Evaluating the conventional technology at 2030 market predictions, it is established that hydrogen production from imported green ammonia can compete with domestic green hydrogen production and potentially emerge as the most cost-effective option for green hydrogen import if optimistic predictions regarding green ammonia costs materialize. In comparing the conventional and emerging technology configurations for LCOH by 2040, it was determined that the membrane-assisted reactor configuration does not significantly outperform the conventional technology, even when considering the most optimistic scenarios regarding the robustness and scalability of this emerging technology.

The carbon emissions from human activities are causing significant harm to the planet, leading to increased temperatures, melting of polar ice caps, rising sea levels, and other negative impacts on the environment. One promising solution is the use of green hydrogen as a fuel source, which could have a much lower carbon footprint than traditional fossil fuels. The production of hydrogen can be achieved through various methods, including the electrolysis of water, which splits water molecules into hydrogen and oxygen. To mitigate these effects and ensure a sustainable future, countries are taking various measures to reduce their carbon footprint, including increasing the use of clean energy sources and improving energy efficiency. Hydrogen storage and transportation pose major challenges since it is the one of the lightest gases leading to low energy densities. Ammonia is emerging as a hydrogen carrier due to its high gravimetric storage densities of hydrogen. It is produced through the combination of hydrogen and nitrogen using the Haber-Bosch process. Ammonia can then be used as a clean and efficient fuel for various applications, such as transportation and power generation. Fluctuations in the hydrogen feed flow rate, resulting from variations in renewable energy sources can significantly impact the pressure and operating temperature within the system. }Morocco holds significant potential for renewable energy development due to its favorable geographic location and natural resources. The geographic location situated close to Europe makes Morocco well positioned for exporting green hydrogen to European markets. The chosen location for the ammonia plant is Boujdour in Morocco due to its excellent wind capacity factor of 67%. Modern ammonia production plants employ control systems to maintain stable pressure. When there is a reduction in hydrogen feed flow rate, these reductions result in severe pressure reductions which would lead to metal fatigue and damage the entire production unit. Hence, these control systems respond by adjusting parameters to sustain pressure within the system. Aspen Plus Dynamics has been used in the present thesis work to model the dynamics of the ammonia synthesis plant. The varying hydrogen feed flow rate is a consequence of renewable energy fluctuations, which is served as the basis for modeling three distinct scenarios involving a 20%, 50%, and 70% reduction in hydrogen feed flow rate. Three distinct control strategies were developed where each control strategy, based on controlling the cooling duty of the condenser, manipulating the brake power of the recycle compressor, and regulating the nitrogen feed flow rate, demonstrated effective stabilization of the system's pressure, even during dynamically changing input conditions. Both linear and step reduction in hydrogen feed flow rate have been considered to gain understanding of the dynamic the behaviour of the system. Significant outcomes were found when a reduction in hydrogen feed flow rate is imposed on all three control strategies. For a 20% reduction in hydrogen feed flow rate, the condenser's duty reduced from -1.2 MW to -1.05 MW, while the brake power of recycle compressor reduced from 12.5 kW to 5.5 kW. Furthermore, the stoichiometric ratio of H2:N2 changed from 3 to 2.8. These changes successfully stabilized the pressure in the ammonia synthesis plant under varying hydrogen input flow rate...

Renewable energy is continuously increasing its penetration in the energy supply network around the world. Due to the intermittent nature of renewable energy sources like solar and wind, storage of excess energy during its availability is vital. Energy storage, especially on the large scale, has recently received a lot of attention from the scientific world and ammonia has been identified as a promising energy storage medium suitable for this application. Factors like high energy density, potential to have minimal carbon footprint and ready existence of suitable infrastructure for handling and transport especially make it an attractive choice. Moreover, ammonia is a bulk feedstock in the chemical and fertiliser industry making it a valuable commodity. A generic model has been developed in MATLAB to assess the economic feasibility of producing ammonia from varying availability of electric power. The model estimates the optimum plant capacity at which levelised production cost is minimum thereby resulting in minimum energy storage cost. Steel industries like Tata Steel produce electric power to satisfy the plant’s operational demand using by-product gases (termed as work arising gases) evolved during the steel making process. An intermittent availability of surplus electric power has been reported at Tata Steel, IJmuiden. The economic feasibility of utilising ammonia to store the surplus available electric power using the developed MATLAB model has been assessed in this study. It has been found that the variable cost due to electric power consumption, the fixed cost of the system and capital cost of the electrolyser significantly influence the production cost of ammonia. The minimum levelised production cost estimated in this study is €997/ton which is almost three times the current market price of ammonia. The system shows potential to produce ammonia at a competitive price when sufficient electric power is continuously available at an electricity price of €10/MWh or lower. Utilising part of the hydrogen produced from the work arising gases in the ammonia production process helps to lower the levelised production cost to around €913/ton. Availability of sufficient hydrogen simplifies the system and it may be possible to produce ammonia at a competitive price when hydrogen price is lower than €1.26/kg. The power to ammonia process shows an efficiency of around 50%. Using gas turbines to produce electricity from ammonia are expected to result in roundtrip efficiencies of around 15%-25%. Research and pilot plants have shown good potential of using ammonia as a fuel in combustion engines and commercial applications are expected to be realised in the near future.