12 Ammonia Flashcards
Why is hydrogen a good green solution for power systems?
It’s a high power molecule that can burn at very high temps.
Examples of systems that hydrogen could provide sufficient power to
Gas turbines
engines
Fusion
Why is ammonia being researched for power systems?
As hydrogen fuel has many disadvantages, as below:
- high NOx emissions when burned close to stoichiometry
- distribution
- handling (explosions and leaks)
- high reactivity
- invisible flames
- lack of infrastructure for distribution
Advantages of using ammonia over hydrogen for fertilising and fuelling
- cost is much lower than hydrogen for long periods/long distances
- Can store considerable quantities of H2.
- lower cost of transportation for ammonia
- higher conversion efficiency than hydrogen
- ammonia is easier to store
What are the main barriers for use of ammonia as an energy vector?
- costs of production
- scale of conversion
- public perception
- economics
What is the estimation for the future of ammonia technology?
by 2024, ammonia blend units will be operating at >2MW
first cargo ship running on ammonia by mid 2020s
Why is ammonia relatively easy to store?
ammonia systems have a much smaller footprint compared to other batteries.
Ammonia tanks can be stored underground (reduces risks and hazards)
How do ammonia and hydrogen compare in regards to their distribution?
Hydrogen is more economical in range: 0-1500km
Ammonia begins to become competitive at 1500km
Ammonia energy transportation is cheaper than H2 for distances above 2500km
∴ ammonia is good for long storage (time and distance) applications
Ammonia combustion and the significance of NOx emissions
NOx emissions are much higher for ammonia than H2 turbines
To reduce NOx:
- use the ammonia as a DeNOxing agent that reacts with the NO molecules
- this should convert some of these NOxes into water and nitrogen
