How ammonia as a fuel source works
Part of what makes ammonia a sustainable fuel source is that ammonia is not made up of carbon. When used as a fuel, it thus does not release carbon emissions into the air theoretically speaking. Ammonia can either be burned using internal combustion engine technology or it can be used in fuel-cell technology; the same technology which hydrogen engines operate off of.
Ammonia powered engines offer numerous benefits other than their zero-emissions. Ammonia is already produced in large quantities for use in fertilizers, and it can be synthesized using renewable energy through a process called green ammonia production. Additionally, ammonia can be stored and transported more easily than hydrogen because it doesn’t require the high-pressure tanks needed for hydrogen, making it a potentially more practical option for global fuel distribution. Plus, because industry already makes use of ammonia, there are transport regulations already in place on how to distribute it safely.
Toyota’s new engine delivers 90% reduced emissions
Toyota has alleged that their 2.0 liter non-platine engine produces 123 kw/h of power and 300 Nm of torque. Additionally, it cuts carbon emissions by 90% compared to traditional gasoline powered internal combustion engines. Additionally, they claim that their 2.0-liter 4-cylinder engine can produce 161 horsepower. “We’ve overcome the pain point of ammonia being difficult to burn quickly and put the fuel to use in the passenger-car industry. Its value to society and for commercial uses are worth anticipating,” says Qi Hongzhong, GAC R&D Center Engineer.
While the engine may seem too good to be true, there are significant challenges which come with producing and implementing ammonia powered engines on a large scale. One of the primary challenges with burning ammonia directly in engines is the formation of nitrogen oxides (NOx), which are pollutants that contribute to smog and acid rain. Special catalysts and combustion techniques are required to minimize NOx emissions, making the development of ammonia-powered engines more complex.
Additionally, although ammonia is already produced and used in various industries, creating a widespread infrastructure for ammonia refueling (especially for transportation) would require significant investment and development, particularly for safety and handling procedures. Further, while ammonia has a high energy density compared to hydrogen, it’s still lower than traditional fuels like gasoline or diesel. This means that ammonia-powered engines may require larger storage volumes to provide the same range or power output.
Ammonia still a viable alternative
Despite its challenges, ammonia has been identified to be a viable alternative in the maritime industry. Several pilot projects are already underway, with ammonia-powered ships being tested. Trucks and buses that require long ranges and high energy density might also benefit from ammonia-powered engines, particularly in regions where electric vehicle charging infrastructure is lacking or where hydrogen infrastructure is not yet feasible.
Ammonia could also be used in power plants. The fuel could be burned or converted into hydrogen in fuel cells to generate electricity, providing a low-emission alternative to traditional fossil fuel plants. While ammonia may not have a strong outlook in the passenger vehicle industry directly, it may play a large role in expanding the role of hydrogen and electric vehicles.
Ammonia-powered engines present a promising but still-developing technology in the pursuit of cleaner, sustainable energy for transportation and heavy industry. While ammonia offers advantages in terms of energy density, storage, and potential zero carbon emissions, its challenges must be addressed for it to become a viable large-scale solution.