Ammonia-fuel cars in the 1970's - pros and cons

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I' ve long been fascinated with the idea of "pivoting" cars from oil & fossil fuels to ammonia. In an alternate word: in the 1970's. A time when electric cars weren't ready by a very long shot. Methanol could be an alternative, but screw carbon, and let's go ammonia (even if NOx might be a problem too - "there ain't such thing as a free lunch" as they say). And no, hydrogen ain't the answer... ammonia is vastly easier.

- what would it take to achieve that ? the Army Nuclear Energy Depot ? more severe oil shocks ? earlier global warming recognition ?

- would ammonia synthesis move the "CO2 pollution" from the cars to the fuel production ?

- in that case, can nuclear help ? what would be the best path toward nuclear-ammonia synthesis ?

Just being curious...
 
Right now, ammonia production is quite energy intensive and is a significant source of CO2, as the hydrogen is produced by reacting methane with steam to produce H2 and CO2.
 
Yes - you have a point. And this issue would be exactly similar (if not worse) in the 1970's. So this is what I mentionned: CO2 emissions would move from car exhausts to fuel production ?
Any way to get clean ("green") ammonia with 1970's technology ? nuclear or not ?
 
Right now, ammonia production is quite energy intensive and is a significant source of CO2, as the hydrogen is produced by reacting methane with steam to produce H2 and CO2.

That’s only due to the availability of cheap natural gas, before the 1990’s nearly all European and a fair percentage of US ammonia was zero CO2. Even today, all Iceland’s ammonia is zero CO2 and there’s still a plant or two producing ammonia the old fashion way.

The original HB process from the early twentieth century used just water/air/electricity.
 
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its still a topic:


I guess, here we have a combine combustion of ammonia with some carbon fuel for starting and enhancing combustion speed.

Ammonia + combustion engine is a very cost effective solution to hydrogen + fuel cell whichalso offers more range. The thermodynamic effeciency will at least be equal
 
Let look into property of Ammonia

A liquid at -33°C, harsh contrast to -150°C of liquid gas or −253 °C of hydrogen
Even better at 8,58 bar pressure you can store liquid ammonia at room temperature
It could also used as Gas like compress natural gas

it far easier to produce and store as Hydrogen

around 1872 build Émile Lamm, a Ammonia gas power internal-combustion engine for Tramway in New Orléans.
in 1943 Belgium, they used Ammonia gas to power internal-combustion engine in city Bus.
also was study and tested the use of Ammonia in fuel cells.
also proposed als remass for nuclear thermal engine on long time deep space mission

So what is problem ?
Ammonia is toxic and dangerous
it's cauterise the lungs if breathe in
it's corrosive to material, but not so bad like acid or hydrogen
Spill Ammonia can damage the environment.
 
I' ve long been fascinated with the idea of "pivoting" cars from oil & fossil fuels to ammonia. In an alternate word: in the 1970's. A time when electric cars weren't ready by a very long shot. Methanol could be an alternative, but screw carbon, and let's go ammonia (even if NOx might be a problem too - "there ain't such thing as a free lunch" as they say). And no, hydrogen ain't the answer... ammonia is vastly easier.

- what would it take to achieve that ? the Army Nuclear Energy Depot ? more severe oil shocks ? earlier global warming recognition ?

- would ammonia synthesis move the "CO2 pollution" from the cars to the fuel production ?

- in that case, can nuclear help ? what would be the best path toward nuclear-ammonia synthesis ?

Just being curious...
If you look and the marine engine/industrial gas turbine engine industry, it's already happening. Current trend is going dual-fuel or multi-fuel, mainly a LNG engine that can also run on ammonia or hydrogen. The upside of ammonia is that there's massive industrial capacity in producing one, since it has various applications, although that isn't always carbon neutral. The biggest probelm though, is the fact that the combustion of ammonia is very different from other types of fuels, that the flame propogation is significantly slower.
 
That’s only due to the availability of cheap natural gas, before the 1990’s nearly all European and a fair percentage of US ammonia was zero CO2. Even today, all Iceland’s ammonia is zero CO2 and there’s still a plant or two producing ammonia the old fashion way.

The original HB process from the early twentieth century used just water/air/electricity.

You mean, something like this ? https://guidehouseinsights.com/news...e-haber-bosch-process-reduce-carbon-emissions
 
The manufacturing of ammonia is an established process, and thus the main challenge is not how to
produce it at an industrial scale with minimum cost, but to how to produce it carbon-free and,
simultaneously, cost efficiently. Given that nowadays the entire ammonia manufacturing process is
conducted within the same plant, all three stages of NH3 generation are generally reliant on a single
type of fossil fuel, of which natural gas is the dominant feedstock (Figure 5). As a result, ammonia
produced conventionally through steam reforming, air separation, and the Haber–Bosch process is
argued to be the direct cause of 1.44 per cent of global CO2 emissions This
is also partly because NH3 represents the most energy-intensive commodity chemical, responsible for
1–2 per cent of global energy consumption. Thus, shifting from the current dominant production
method of ammonia to ones that are not based on hydrocarbons and do not emit CO2 could be viewed
as a means of not just facilitating a green energy economy but also of decarbonizing an energyintensive
chemical product.

For the Haber–Bosch process, a simple switch from fossil fuels to electricity will not lead to an increase
in efficiency, but it will cut emissions by approximately one third (Bañares-Alcántara et al. (2015). If the
phases prior to the ammonia synthesis loop are also electrified, there will be positive environmental
impacts as well as an efficiency advantage. For example, electrification of the hydrogen generation
phase (replacing steam reforming with electrolysis) will increase the efficiency of the subsequent
stages, as generating high purity hydrogen can help to prevent inactivation of catalysts. 9 Nitrogen
generation and ammonia synthesis are generally more flexible in terms of the energy type that can be
used for their production. In other words, these processes can switch from fossil fuels to electricity
without a major hurdle and thus be adjusted to the needs of decarbonization policies through running
on non-hydrocarbons – electricity generated by either nuclear power or renewables. However, this is
not straightforward for hydrogen. Thus, the key challenge of green ammonia production is carbon-free
hydrogen production.

So, why don't we use nuclear to switch NH3 production to electricity - for a start ?
 

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I recall meeting with a start up who were looking at this as an alternative to grid battery storage - making hydrogen by electrolysis when electricity demand is low and you have oversupply from renewables and converting it to ammonia to store. Combustion of the ammonia to drive turbines and feed back into the grid in periods when the electricity price is high and collect the nitrogen from the flue to recycle. It was a few years ago with cheaper peak time electricity so the economics were marginal then but may be better now. Possibly even worthwhile other market in nitrates for fertilisers as natural gas prices are a multiple of what they were then
 
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So, why don't we use nuclear to switch NH3 production to electricity - for a start ?
Because the Green weenies lose their collective minds at the word "nuclear".

Ammonia leaks are also more than a bit scary. I live relatively close to a couple of places with large ammonia-based refrigeration plants and one had an ammonia leak a couple months back. Evacuated about 10 blocks square.

The sneaky trick I like is to use engine exhaust heat to crack ammonia into hydrogen and nitrogen, then feed that gas stream into the combustion chamber as the pre-heater for burning ammonia directly. I think it would only work in a gas turbine, though.

Another sneaky trick I have seen is using exhaust heat to boil ammonia held under a bit of pressure and use that ammonia gas to spin a turbogenerator. Once through the turbine, the ammonia has cooled down to liquid again. If scaled correctly, that will pull all the waste heat out of the exhaust, down to about 20degC or less. And if properly designed, the entire loop can run on natural circulation, but I think most cogeneration systems still use ammonia pumps.

Those two can even be combined into a single generation plant if you're smart. Ammonia-burning gas turbine driving a generator and liquid ammonia cogeneration loop in the exhaust.
 
I recall meeting with a start up who were looking at this as an alternative to grid battery storage - making hydrogen by electrolysis when electricity demand is low and you have oversupply from renewables and converting it to ammonia to store. Combustion of the ammonia to drive turbines and feed back into the grid in periods when the electricity price is high and collect the nitrogen from the flue to recycle. It was a few years ago with cheaper peak time electricity so the economics were marginal then but may be better now. Possibly even worthwhile other market in nitrates for fertilisers as natural gas prices are a multiple of what they were then
There's a time in June where I live when the wholesale electricity price is zero, as they're flushing the salmon young out to sea. I think the power companies just use that to keep their rates nice and low.
 
So, why don't we use nuclear to switch NH3 production to electricity - for a start ?
The question should be "why don't we have more nuclear?" instead of "why don't we have more nuclear for ammonia". The answer, we are all too aware of. Also, talking about using nuclear energy for alternative fuel production, well there is already VHTR for hydrogen production, so it's not like people ain't thinking about it.

I recall meeting with a start up who were looking at this as an alternative to grid battery storage - making hydrogen by electrolysis when electricity demand is low and you have oversupply from renewables and converting it to ammonia to store. Combustion of the ammonia to drive turbines and feed back into the grid in periods when the electricity price is high and collect the nitrogen from the flue to recycle. It was a few years ago with cheaper peak time electricity so the economics were marginal then but may be better now. Possibly even worthwhile other market in nitrates for fertilisers as natural gas prices are a multiple of what they were then
Well, storing hydrogen doesn't need to specifically be ammonia. There are all sorts of LOHC and metal hybride researches going on around the world since hydrogen has been the next big thing for literaly decades by this point. By the time we are able to achieve mass-scale hydrogen-ammonic ESS, I'm pretty sure our technological and industrial maturity regarding FCs, be it PEM with reformers or direct conversion FCs, would've eclipsed ammonia combustion in a lot of industrial energy production applications, especially when it comes to electricity production for the grid. Though I gotta give that using ammonia-ran gas turbines would give some competitive advantage when it comes to using pre-existing infrastructures. So the question would come down to if gas turbines will stay more economical than FCs for the long run.
 
What is the toxicity of ammonia vapor compared to gasoline vapor?

Is an ammonia fueled car something you want in your suburban tract house's garage right under your kids' bedrooms?
I remember being able to smell the gasoline from my parents' cars the couple times we lived in houses with that configuration.
 
What's the energy density of ammonia vs diesel or gasoline? Batteries aren't close yet but with as much capital and research is being dedicated to battery tech I'm pretty confident sooner or later they're going to get there.

Retooling an entire industry to produce a new fuel when there's so much sunk cost into the alternative seems unlikely at this stage. I don't believe the ag and industrial ammonia production capacity is anywhere near sufficient to supply the world's car and truck fleet.
 
What's the energy density of ammonia vs diesel or gasoline? Batteries aren't close yet but with as much capital and research is being dedicated to battery tech I'm pretty confident sooner or later they're going to get there.

Retooling an entire industry to produce a new fuel when there's so much sunk cost into the alternative seems unlikely at this stage. I don't believe the ag and industrial ammonia production capacity is anywhere near sufficient to supply the world's car and truck fleet.
Energy density of ammonia compared to gas is about 1/3 by weight, 1/2 by volume.

And batteries are about 1/100 by either (though due to different consumption pattern it's a bit closer to 1/50). Yes, the high density lithium exotics, not wimpy alkaline or lead-acid batteries.

What is the toxicity of ammonia vapor compared to gasoline vapor?

Is an ammonia fueled car something you want in your suburban tract house's garage right under your kids' bedrooms?
I remember being able to smell the gasoline from my parents' cars the couple times we lived in houses with that configuration.
You'd need a more tightly sealed system, but that's been a thing for more than 120 years with ammonia plants. Gasoline itself is toxic due to any benzene in the mix.

Ammonia is something you can smell long before it gets up to toxic exposure levels. You can smell ammonia starting at 5 parts per million (5ppm) in air, but the irritating effects start about 1700ppm and dangerous toxic effects don't start happening until about 2500ppm. Levels of 100ppm are safe to be around for an extended time. Having a big ammonia leak, where levels are over 5000ppm, is an immediate threat to anyone around it, though. 10,000ppm will start burning the skin of anyone exposed (you'd see this with people wearing forced air respirators). And I mean chemical burns, not irritation that feels like it's burning. (source: https://www.ncbi.nlm.nih.gov/books/NBK546677/ )
 
.

The sneaky trick I like is to use engine exhaust heat to crack ammonia into hydrogen and nitrogen, then feed that gas stream into the combustion chamber as the pre-heater for burning ammonia directly. I think it would only work in a gas turbine, though.

Another sneaky trick I have seen is using exhaust heat to boil ammonia held under a bit of pressure and use that ammonia gas to spin a turbogenerator.

This would work much better in a piston engine, since you can use the coolant heat for boiling and you have higher and more constant exhaust gas temperatures. For a vehicle, you would need a hybrid drivetrain to avoid low engine loads. The marine industry is doing a lot of research for ammonia as fuel, but they would prefer a solution based on existing Diesel engines were a small amount of Diesel is used to ignite the ammonia. As fas as I have seen the results, this approach doesnt really work well. Unfortunatelly, they are afraid of crackers and hydrogen, but this is the only way which would work!
 
This would work much better in a piston engine, since you can use the coolant heat for boiling and you have higher and more constant exhaust gas temperatures.
Well, using exhaust gas heat seems to be unique to stationary generator/cogeneration installations. The idea is to extract every available BTU from the fuel and turn as much as possible into electricity. The ammonia boiler loop is well past any turbochargers, catalysts, and other exhaust treatment systems.

For a vehicle, you would need a hybrid drivetrain to avoid low engine loads. The marine industry is doing a lot of research for ammonia as fuel, but they would prefer a solution based on existing Diesel engines were a small amount of Diesel is used to ignite the ammonia. As fas as I have seen the results, this approach doesnt really work well. Unfortunatelly, they are afraid of crackers and hydrogen, but this is the only way which would work!
I think they're going to have to get over their fear of catalytic crackers, but I'm not anywhere near as far up on my diesel tech as I am on aircraft or ships.
 
The cracker could be placed between the exhaust of the cylinder head and the turbochargers, in combination with a stoichiometric AFR, there would still be enough heat to drive the turbos.

Ammonia is btw. a much better additive for anti-NOx treatment as an urea solution, so that the NOx emissions can be reduced very effectively. In fact, the NOx emissions and residual ammonia emissions need to be balanced out, so that they will cancel each other.
 
Ammonia is something you can smell long before it gets up to toxic exposure levels. You can smell ammonia starting at 5 parts per million (5ppm) in air, but the irritating effects start about 1700ppm
Irritating effects brings to mind that time in the late 1980s when I briefly worked in a department store & they wanted me to clean the display glassware with an ammonia and water mix. That lasted until I started sneezing blood all over it.

(now, granted, we later learned my body had a couple defects which also contributed to the thing, but, still ...)
 
The cracker could be placed between the exhaust of the cylinder head and the turbochargers, in combination with a stoichiometric AFR, there would still be enough heat to drive the turbos.
I'd rather park the cracker at the turbo downpipe, or in a large industrial engine on the turbo exhaust scroll directly.
 
Cooling the turbo housing with cracking amonia would be a good option. after the turbine, the exhaust temperature is much lower, these would make it difficult to make it work at lower power outputs.
 
Not a car, not the 1970s, but perhaps of related interest,

Shipowners and industry analysts say they expect ammonia to play a pivotal role in decarbonizing cargo ships. But there's a crucial caveat: No vessels of any size today are equipped to use the fuel. Even if they were, the supply of renewable, or “green," ammonia produced using carbon-neutral methods is virtually nonexistent. Most ammonia is the product of a highly carbon-intensive process and is primarily used to make fertilizers and chemicals.

Recently, though, a handful of projects aim to change that. Finland's Wärtsilä plans to begin testing ammonia in a marine combustion engine in Stord, Norway, by late March. Germany's MAN Energy Solutions and Korean shipbuilder Samsung Heavy Industries are part of an initiative to develop the first ammonia-fueled oil tanker by 2024.

Also by 2024, the Viking Energy is poised to become the first vessel propelled by ammonia fuel cells. The Norwegian energy company Equinor (formerly Statoil) charters this offshore supply vessel, which currently runs on liquefied natural gas. Chemical giant Yara will provide the green ammonia, which it plans to produce at a plant in southern Norway.

Japan's Mitsubishi Heavy Industries (MHI) is also exploring the potential of ammonia in Asia, having concluded a memorandum of understanding to look into developing a 100% ammonia direct combustion power plant on Jurong Island. This will study the possibility of setting up a plant that could produce carbon-neutral electricity and help stimulate ammonia demand in preparation for the expected need for ammonia bunkering.

Meanwhile, trading firm Itochu has signed an initial agreement with power producer Malakoff Corporation Berhad to potentially develop an ammonia terminal in the Johor Straits between Singapore and Malaysia.

And in Australia, Kanfer Shipping and Oceania Marine Energy have signaled their intention to bring the world's first ammonia-ready LNG bunkering vessel to the country, as they look to develop the zero-emission shipping industry.

MAN Energy Solutions is developing a fuel-flexible, two-stroke ammonia engine as a key technology in the maritime energy transition

Green ammonia is among several synthetic fuels key to establishing a greener shipping industry in the near future. MAN Energy Solutions aims to have a commercially available two-stroke ammonia engine by as early as 2024, followed by a retrofit package for the gradual rebuild of existing maritime vessels by 2025.
 
And then from one of the shipping lines,

Press Release
Concept Design for Ammonia-Fuel Ready LNG-Fueled Vessel Completed
Mar. 03, 2022

Nippon Yusen Kabushiki Kaisha
MTI Co., Ltd.
Elomatic Oy

Nippon Yusen Kabushiki Kaisha (hereinafter, NYK), MTI Co., Ltd. (hereinafter, MTI), and Elomatic Oy, a Finnish maritime consulting and engineering firm (hereinafter Elomatic), have completed the development of a concept design for an ammonia-fuel ready LNG-fueled vessel (ARLFV) for the transition to a future marine fuel.
 
Fuel cells for a big container ship would be way to expensive and not even offer significant higher efficiency as the two strokes (55 % in combination with exhaust heat recovery). I'm looking forward to the MAN solution and I'm hoping they will use a cracker, but I doubt it. Maybe they will use LNG to improve combustion instead, which wouldn't be a 100 % CO2 free solution.
 
Forget ammonia engines, how about ammonia fuel cells?

Liquid hydrogen is an absolute pain to store, but ammonia on the other hand is as easy to store as propane.
 
Forgett about ammonia fuel cells, you need an exessive cleaning effort to feed them with pure hydrogene or high temperature fuel cells which are unsuited for transport.
 
Forgett about ammonia fuel cells, you need an exessive cleaning effort to feed them with pure hydrogene or high temperature fuel cells which are unsuited for transport.
Not that difficult, especially since the fuel cells generate heat anyways for the cracker. Probably not enough heat natively, though, as most crackers need to run at 600-900degC and 50-100bar.

But it's much simpler to put a cracker on a combustion engine, as that lets you recover heat that would otherwise be wasted.
 
High temperature fuel cells are no option for mobility, since they need to run continously and are very expensive. Low temperature fuel cells are prone to every kind of poisening an need much effort for cleaning to produce pure hydrogen. They also have very low waste heat temperature, so that cracking needs to be done by burning ammonia instead of using waste heat.

A ship powered by high temperature fuel cells would be around 7x times more expensive than current ships with a Diesel engine (best case scenario).
 
Seems the Army did not cared about economics, so the Energy Depot would have used a nuclear reactor to go water hydrolysis and then turn the hydrogen into ammonia by adding air's nitrogen.
In contrast with that, the attached document suggest to go nuclear heat on ammonia steam reforming. Main issue of course is the CO2 (he even mentions worries about a so-called greenhouse effect... sigh) but the author suggest to turn it into a commodity rather than a plague.
 
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