Comprehensive evaluation of NH₃ production and utilization options for clean energy applications

Ammonia is not only a fertilizer but also an alternative fuel for transportation and power generation. It can easily be adapted to fuel both diesel generators and larger utility power plants. The ability of being produced from renewable energy sources allows on-site ammonia production where it is needed. The high hydroelectric, wind, and solar energy source potential of Canada make the energy storage attractive using ammonia. Ontario, with decreasing electricity prices, has potentials for on-site ammonia production from hydropower. Solar energy, as the most abundant source of energy in the world, can be directly utilized for ammonia synthesis via various routes such as electrochemical and thermochemical cycles. Canada have significant potential of renewable resources such as hydropower and wind power. Ammonia can be transported via ocean tankers or pipelines. Besides being a zero emission fuel in the utilization process, about 30% greenhouse gas reduction is possible using renewable energy such as wind in the ammonia production when compared to conventional unleaded gasoline. Compared to propane, greenhouse gas production decreases about 18%. Hence in the overall life cycle, ammonia has significant environmental advantages. Even if ammonia is produced from hydrocarbons, it has similar greenhouse gas emissions with solar energy based route. It is important to emphasize that an ammonia driven passenger vehicle releases less greenhouse gas emissions than compressed natural gas (CNG), liquefied petroleum gas (LPG), diesel, and even hybrid electric vehicles. Considering vehicle and fuel production together, emissions from an ammonia-fueled passenger car is very close to electric vehicles per km traveled as even lower in a few routes. An ammonia-fueled vehicle can save 100 g of greenhouse gas per km compared to gasoline when the complete vehicle and fuel life cycle is considered. Depletion of abiotic resources is moderately lower for conventional ammonia production, which is originated from natural gas, than liquefied natural gas, diesel, petrol and propane fuels. In this report, detailed background information about production and utilization of ammonia is presented in Chapter 1. In Chapter 2, an alternative ammonia synthesis method is experimentally realized and tested. The selected route is molten salt electrolyte based electrochemical ammonia production. In Chapter 3, the required hydrogen for ammonia synthesis is produced using photoelectrochemical route and integrated to ammonia synthesis. The experimental results are presented under different conditions. Chapter 4 explains ammonia production from hydrocarbon sources such as natural gas. The comparative results for liquefied natural gas (LNG) and ammonia are given for production and transport phases. Chapter 5 investigates the usage of ammonia in maritime applications and performs a life cycle assessment. In Chapter 6, ammonia is evaluated as a potential fuel for aviation industry and the performances of alternative fuels are comparatively presented. Chapter 7 performs a life cycle assessment for ammonia usage in road vehicles whereas in Chapter 8, ammonia is produced using different routes and decomposed on-board for hydrogen driven vehicles. On-board ammonia electrolysis is also analyzed and presented. Chapter 9 investigates the cost of photoelectrochemical hydrogen and ammonia using exergoeconomic approach and the system is scaled-up in Chapter 10 to find the total cost of hydrogen and ammonia.