Ammonia as fuel
Ammonia contains 1.5 times more hydrogen than liquid
hydrogen for a given volume at room conditions
Ammonia (NH3) contains about 17.65 % of hydrogen by weight, it means that 1 litre of ammonia
contains about 1.2 m3 of hydrogen at room conditions.
Liquid hydrogen has a density 0.07 kg/dm3, it means that 1 litre of it contains about 0.8 m3 of hydrogen
at room conditions.
Therefore 1 litre of ammonia contains 1.5 times more hydrogen than 1 litre of liquid hydrogen at
room conditions.
It produces hydrogen for fuel cells having an efficiency between 60% and 70 % that is more than double
of a gasoline engine!
It contains around 12.000 kj per litre against 30.000 kj per litre of gasoline, but because of its high efficiency
an ammonia car would run the same kilometers of a gasoline car with the same volume of
fuel (I have not considered the heat required to produce hydrogen from ammonia because it can be
recovered from fuel cells operating at 500°C.).
There are prototype cars that run on ammonia.
Ammonia is not toxic today
Scientists have found a system against ammonia toxicity.
Ammonia is stored in a metal ammine complex that can be held in the hand, infact
the ammonia vapour pressure for this ammine(Mg(NH3)6Cl2) is 0.002 bar at room conditions!
This ammine has a density about 1.2 kg/dm3 and 1 litre contains 1.2 m3 of hydrogen at room conditions
therefore 1 litre of metal ammine complex contains 1 litre of liquid ammonia!
Energetic efficiency of ammonia from hydrogen is high
Actually ammonia production from natural gas has an energetic efficiency around 65%.
If only hydrogen is used then this efficiency can increase infact this process only needs about 13% of
hydrogen to eliminate all the oxygen(using it) of the air to produce nytrogen.