Ammonia Fuel Network Conference - 2008

This is a guest post by Neal Rauhauser, known on TOD as SacredCowTipper. He is the executive director of the Stranded Wind Initiative.

The fifth annual Ammonia Fuel Network meeting was held September 29th and 30th in the McNamara alumni center on the University of Minnesota's Minneapolis campus. One hundred and forty registered attendees crammed into a sometimes standing room only auditorium to hear 29 presentations ranging from highly technical catalyst development to ammonia safety to updates on various clean production methods.

The sense among the attendees is that we're at a tipping point – the end of the beginning for ammonia fuel, and the beginning of a much more broad interest in the only hydrogen carrier that can be produced renewably.

Per closing remarks by Dr. John Holbrook, the co-founder of the network, this is probably the last free annual meeting. If they had they pushed a little harder, they could have doubled the number of attendees.

The presentations fell into several broad categories: improved ammonia synthesis methods, ammonia combustion efficiency, fuel cell development, ammonia safety, various energy storage schemes, and five ammonia production schemes, four of which were based on renewable energy sources.

Ammonia synthesis has remained essentially unchanged for the last century. Hydrogen and nitrogen are mixed at pressure in a vessel with an iron catalyst producing heat and ammonia. Nitrogen is simply extracted from the air and hydrogen has a variety sources; electrolysis, stripping from natural gas using steam methane reformation, or production using what is called a "switch" reaction, pulling hydrogen from water using carbon monoxide produced via incomplete combustion.

The most promising advance in synthesis seen so far has been the development of a process called solid state ammonia synthesis (SSAS), which is conceptually an ammonia powered fuel cell being run in reverse. Energy use for this system will be two-thirds of what is required for a hydrolysis/Haber Bosch and the capital cost will be less than half. The technology is at the bench top stage, and many of the attendees, myself included, came together at the end of the conference to see if we could identify a source of funding for the estimated $800,000 needed to bring the technology to pilot stage. There was no direct report on progress with SSAS this year, but you can view the one given for the 2007 conference.

Ted Hollinger of the Hydrogen Engine Center was the first of three presenters covering the use of ammonia as a fuel in piston engines. HEC has been building alternate fuel engines based on the Ford 300-6 for several years and they've had a unit powering an irrigation system in California. The only troubles reported had to do with a piece of third party electronics; the engine itself has been trouble free across 1,800 hours of operation. Durability and cleanliness were key, and performance in these areas was fine. The other reports were very detailed analyses of the behavior of ammonia as an internal combustion fuel; ammonia is hard to start and slower burning than liquid hydrocarbon fuels, but with some attention to detail it performs well in terms of emissions.

Bill Kumm of Arctic Energies, Ltd. spoke on the use of ocean thermal energy conversion to produce ammonia. The approach that was quite reminiscent of the concept of wind driven arctic ammonia production coupled with geo-engineering delivered by Dr. Homer Wang a few years ago. I asked Kumm and he thought that the cold water draw from OTEC would have no effect on a hurricane even if we built a vast number of platforms in the Gulf of Mexico. Dr. Wang's proposal was quite different, as the cryogenic storage of ammonia would allow for the production of water ice, with the albedo increase effect making dramatic changes in exchange for a relatively small amount of energy.

The energy storage schemes ranged from high level policy view provided by Bill Leighty of the Leighty Foundation to a clever solar thermal ammonia based storage loop described by Rebecca Dunn of the Australian National University. One of the big problems in renewable energy is that wind is irregular and solar is periodic; the firming of sources such as these is vital to a conversion to an all renewable energy economy.

Alaska's Energy Authority is looking into the use of ammonia as a fuel in many locations. They have remote villages where electricity is entirely generated by diesel delivered in World War II era flying tankers, locations with a thousand residents that need $40 million worth of power line construction to get on the grid, stranded hydroelectric resources everywhere, and fantastic wind and wave energy available in the Aleutian Island chain. David Lockard's presentation was a fascinating gateway into a world already facing many of the issues peak oil will bring to all human society.

Mark Huberty and his advisor Dr. Ed Cussler have taken a different approach on the firming issue, modifying a Haber Bosch reaction chamber to contain a simple ammonia absorbing salt. Once this is perfected, ammonia will be produced in small batches using wind driven electrolysis and nitrogen separation via a simple membrane plant.

The ammonia production projects were of varying caliber and maturity. The University of Minnesota Morris campus has a wind driven ammonia plant on the build but that is purely research oriented, with just a single 1.65 Vestas V-82 turbine as its power source. Dakota Gasification is running a coal based ammonia production facility with CO2 sequestration, the only non-renewable-energy system and the only one currently in production.

Our presentation on a project in the planning stage for renewable ammonia from Niagara Falls hydroelectric power was very well received, and I was quite pleased to see Freedom Fertilizer's presentation also on the docket, as I had a hand in writing the work that recently got them a $100,000 USDA value added producer grant. Kathy Showalter of Enerjyn was the lead grant writer on this one, and they have an extensive practice in renewable energy projects.

Freedom Fertilizer's grant was written with a great deal of assistance from those involved in the Stranded Wind Initiative, and the intent was to leverage this small grant into a full scale ammonia production facility. A year into our explorations, it is now known that the traditional Haber Bosch synthesis method must have a full time grid connection to behave properly, so we've undertaken a patent application for some modifications to Haber Bosch which will enable it to perform with an irregular power input. I suspect both the improved Haber Bosch and solid state ammonia synthesis will be commercially viable, with the former being used in places where waste heat would have commercial applications and having a lower bound in the tens of millions of dollars as far as plant cost, while the later will be used across a broad spectrum of projects thanks to its ability to scale from a single tube up to entirely consuming the output of a large hydroelectric facility.

There were three presentations on ammonia safety. The consensus is that ammonia can be stored safely, even in urban settings, and that it'll make a passable motor fuel as well, but the Department of Energy does not view ammonia as a potential hydrogen carrier. Like so many other things in the world today, everyone is waiting patiently for an energetic new Congress and President Obama to correct these various misconceptions.

These are exciting times for renewable ammonia production given the existing demand for fertilizer and the soon to be booming need for this carbon free fuel. This report is not an exhaustive review of what was presented but you should find all of the presentations, albeit in PDF form, in the link at the top. If you have further questions the authors are generally very accessible and will have included their email addresses in their presentations.

I'm reading the book Master Mind: The Rise and Fall of Fritz Haber, the Nobel Laureate Who Launched the Age of Chemical Warfare. I've just finished the title.

Seriously, I skipped ahead to the chapter on N fixation. Haber developed the process (after being talked into the project) and Bosch scaled it up. Iron catalysts were used early on, but without much success. The first successful catalyst was osmium, and Haber advised BASF to buy all the Os they could find. He subsequently found that the more abundant uranium worked as well, and I guess they eventually tried iron again. The big key to success was using both high pressures (higher than thought possible on a large scale reactor) and temperatures.

And the book also deals with his work in the development of chemical weapons including Zyklon-B, which was later used to gas Haber's own relatives by the Nazis (Haber had died a pauper in exile by then). I'm still reading.


One of these projects will need to start showing decent profit or high EROEI soon. For example the solar ammonia dissociation project for Whyalla Australia is in the shadow of nearby uranium developments. Moreover some have suggested nuclear hydrogen is a better route to nitrogen fertiliser. I agree that stored 'value' is the key to intermittent power output, whether that value is a fuel, fertiliser or electricity on demand.

I'm sure Fritz Haber would approve being the all time eager beaver. A recent TV documentary showed black and white footage of him enthusiastically supervising poison gas trials. I believe his wife used his gun to commit suicide because of that.

Given the job creation that occurs we get access to NYPA power at the $0.02/kwh range. Including operations cost and debt service our output will cost about $350/ton and the current retail market is $1,100 per ton in the area.

I can't speak to EROI on this one - how far back do we go? The steel in the plant itself? We can calculate the energy in the ammonia ... but the instigator of our project is a biodiesel producer making the switch from soy to canola. It's a complex issue and fertilizer is an important commodity - we'll forge ahead and leave the EROI debate to those better equipped to engage in it.

Thanks for the article, and good for you in not getting too wound up into the EROI debate!
If there are not subsidies involved, EROI should show itself in the dollar costs, and those are a lot easier to keep track of.
I'm promising myself I will have a good read and try to get to grips with some of your sources, but it is quite daunting.

How efficient is the ammonia fuel cell?

I spoke with a fuel cell vendor yesterday in passing, and learned that essentially all current fuel cells "run" on hydrogen, but some have integral reformers for other fuels (generally with added complexity). Is this true for ammonia as well?

How reversible is the ammonia fuel cell process? A "battery" mode for a fuel cell would of course address many more applications, and integral reversibility would seem to me to be a holy grail of fuel cells.

Other more mundane considerations for ICE or fuel cell use would be the overall cycle efficiency and cost (ammonia creation from energy in to useful work out), reliability, cycle life, power load, operating characteristics, and so forth.

I know there have long been discussions about whether ammonia is "too dangerous" for refrigeration and transport applications. Is the prevailing view that it is "safe enough", compared to petro fuels, for vehicle or generator use?

I've honestly not paid attention to the ammonia fuel cell stuff. I've visited and wrote about the Hydrogen Engine Center, which has been running a Ford 300-6 on an ammonia/propane mixture in an irrigation application. They got 1,800 hours of operation this year and the only troubles were from third party components.

I will ask Dr. Holbrook about the forward/backward potential for the solid state ammonia synthesis process and I'll post his response here.

The ammonia guys think ammonia is safe enough. I missed the three presentations in this area because I had some Dakota wheat farmers cornered in the lobby talking about making ammonia from hydroelectric power. My opinion, at least from an ICE perspective, is that we ought to be running it as a farm fuel - there are the stage four requirements coming in 2011 and ammonia would dramatically reduce particulates.

My interest in alternative fuels is for telecom - not only my area of personal expertise but a necessary infrastructure asset in a post-oil world. A fuel cell at the right price point can replace backup generators today, but ammonia could potentially just run the ICE generator as well.

For these standby applications, maintenance is a significant issue, so a long-lived, high-reliability fuel cell would offer many advantages over ICE generators. With subsidies even hydrogen fuel cells come close to break-even, according to those doing trials. I need to look at cost numbers (fuel, engine/fuel cell, maintenance, support, etc.) for NH3 and better understand pros and cons.

A low-cost reversible process would permit a new set of applications that cannot be cost effectively addressed by batteries today. Peak shaving with off-peak charging would be the initial goal, followed by local charging with sporadic wind and solar. Flow batteries are the best option I've come up with so far, and I'm looking at costs for the vanadium solution now.

I'm 100% behind adding NH3 to the option list for wind storage -- that's going to be a critical need. Cost is important, but any process than can readily deal with the sporadic nature of wind can tolerate some added cost -- peak-ready loads are valuable just like on-demand generation in flattening out the supply/demand curves.

The large vanadium redox battery housed in a shed in King Island Australia seems to be a disappointment. The wind power system still requires frequent diesel backup as the battery merely buffers the output for a couple of hours. If a tungsten (scheelite) mine re-opens on the island it will be powered by an underwater alternating current cable fed from the State grid. They are also looking at seafloor mounted water turbines.

There seem to be some unpleasant intellectual property issues with vanadium, else surely more than a handful of companies directly tied to the original invention would be producing units?

On the one hand, I've seen low vanadium electrolyte costs estimated for large volumes, like $50 to $150 per kwh of capacity. On the other hand, I hear of very high system costs, and limited storage. For the example you state, it would seem to be a simple and cost-effective matter to just add a lot more vanadium flow storage, yet that seems not to be considered.

Volumes of scale and process refinement could likely help, but that requires some outside money and intellectual property access.

Here are vendor-stated costs for the vanadium battery:

The assumptions used for the cost of the 5 kW stack and the electrolyte system respectively
Stack cost $5,410
Electrolyte cost $118 / KWh of storage
For example, for 8 hours or 40kWhs of energy storage, the electrolyte cost is $4,470 giving a total
capital cost of $10,150.

Unfortunately, they say this is a "target" based on volume manufacturing and a 2x sale-price mark-up. I don't know of many companies that survive on 2x for relatively high-tech products while supporting an engineering wing, so those numbers are probably a long time coming.

Note that time honoured lead-acid starter batteries for cars work out about $200 per kwh, albeit shallow draw and clunky. But no pumps, easy recycling.

The addition of capacitors to standard lead acid batteries together with some over-capacity transforms the lifespan of lead acid, as it is deep discharge which damages them:


Fuel cells powered by ammonia are already being marketed in Europe by Diverse Energy Ltd for telecom and small diesel back-up applications.

These appear to be PEM type hydrogen fuel cells where the hydrogen is stored in the form of ammonia (or propane or hydrogen), and then cracked to hydrogen and nitrogen and purified for feed to the PEM fuel cell.

It is not clear at this point how the company generates the ammonia (i.e. wind, solar, or grid), but likely it is purchased merchant ammonia for now.


Thanks for the link.

Sounds complex, but a liquid fuel is sure a lot more palatable than gaseous. It will be interesting to compare full TCO for hydrogen vs ammonia or propane.

Ammonia has been used directly in solid oxide fuel cells and in cracked form (thermocatalytically split into H2 and N2) in lower-temperature polymer electrolyte fuel cells with typical 50% electrical efficiencies. Any well-designed fuel cell will be able to achieve this kind of chemical-to-electrical conversion efficiency. This efficiency level is very similar to those for hydrogen fuel cells, thanks to ammonia's small required energy for decomposition.

Nice to see a genuine expert showing up to comment on this area, since I'm pretty much helpless there.

You should write at length and further school us on this topic - a few more paragraphs wouldn't kill you, would it? :-)

Sure... I'm not much of a blogger but I'll check back now and then to see if there are any burning fuel cell questions.

But everybody should remember that a fuel cell is just the icing on the cake; using an ammonia-fueled device is the easy part - the real challenge is gaining acceptance for its use as a fuel in the first place.

A fuel cell gives you chemical-to-electric energy with less total losses than an ICE-powered genset, but at a greater capital cost. Fuel cell costs have come down quite a bit in the last several years, let's hope that trend continues!

I heard cost estimates this week of $7K per kilowatt for hydrogen fuel cells. Are NH3 cells similar? An ICE generator is of course significantly less. For low-run use, fuel cost is less significant than considerations such as fuel shelf life, genset total maintenance, run-time between planned maintenance events, and other factors that play into total cost of ownership.

Do NH3 fuel cells get the same incentives as H2?

This table illustrates fuel cell incentives for a few states, as compiled by BCI (a renewable energy vendor/integrater):

               Incentive                                        State        Federal
Federal         30% tax credit or $3,000 per KW                              30%
Connecticut     Local option property tax exemption             $405*  
Florida         75% tax credit of capital and        
                operating costs, up to $12,000 per unit         $12,000
                Sales tax exemption(6%)                         $1,169*
Maryland        30% tax credit or $1,000/kW         
                if fuel cells serve a green building            $5,000
New York        20% tax credit up to $1,500 per 
                unit; includes installation costs               $1,500
Washington      Sales tax exemption(7% -9.3%)                   $1,364*

At a fuel cell installed cost of $5K-$7K per kw, they show an advantage over batteries over the long-term for new-build application where a battery system would require a chassis and HVAC. This is perhaps not universally the case, so batteries will probably still "win" for some applications even with the incentives.

What precautions would have to be in place, to prevent the production of nitrogen oxides? Recent work has shown that nitric oxide is a killer at quite low doses.

The nitrous oxide production is actually lower in a properly controlled ammonia engine. Those form at high temperatures and the ammonia burns relatively cold. There is potential for direct ammonia emissions from unfinished combustion. Both are easily cleaned up with a standard catalytic converter.

Sorry to burst your balloon but..
Is ammonia any better than carbon?

Nitrous oxide has 296 times the global warming potential
(GWP) of carbon dioxide.

At 11.5 MJ/liter, it's a less efficient energy carrier than methanol at 15.6 MJ/liter.

It is produced by the nitrification of ammonia fertilizers.

Obviously using wind to make ammonia is a clear winner, but as a fuel does it make sense?
What do you say to these obvious arguments?

majorian -

I really have a hard time seeing why using ammonia as a fuel is better than using the ammonia as the fertilizer for which it was originally intended.

If one is going to use either wind or solar to generate electricity, then going through all the trouble to use that energy to make ammonia begs the question: why not just pump that electricity to the grid (or to local use) and be done with it? If the answer to that question is energy storage, then I submit that there are easier and less expensive ways of storing the energy output of wind and solar power than in the making of ammonia for use as a fuel.

On the other hand, if the purpose is to displace the use of natural gas to make ammonia fertilizer, then I would see that as a beneficial use and thus be in favor of it.

The convoluted path of wind => mechanical => electrical => chemical (NH3) => heat => mechanical => electrical seems like the thermodynamic equivalent of digging a hole and then filling it back up again, then digging it again......

The convoluted path of wind => mechanical => electrical => chemical (NH3) => heat => mechanical => electrical seems like the thermodynamic equivalent of digging a hole and then filling it back up again, then digging it again......

Unfortunately, this 'hole digging' covers just about every form of energy 'production' with a storage. Even if you look at good, old-fashion dino-oil, we have Solar => biological => chemical (over a long time) => chemical (refining) => heat => mechanical => electrical (or motion). The only EROEI advantage with petroleum is most of the hard work is already done before we pump it from the ground.

Personally, I think ammonia as a storage medium has a lot of potential but gives me the shivers at the same time. I like it better than hydrogen, that’s for sure. And it would seem to scale easier than batteries (which need maintenance and replacement)

If one is going to use either wind or solar to generate electricity, then going through all the trouble to use that energy to make ammonia begs the question: why not just pump that electricity to the grid (or to local use) and be done with it?

Mechanized agriculture is an intrinsically decentralized process. It seems like there would be substantial capital savings in being able to use existing ammonia distribution network and on-farm storage capacity for ammonia as a fuel as well as for fertilizer applications.

The focus on less capital-intensive ammonia production technology is looking to the use of ammonia production as a customer for wind or other volatile renewable energy when wind production is in excess of local demand ... that is, addressing intermittency on the demand management side, while replacing natural gas use for ammonia production.

Obviously, the envisioned applications at the conference would be a much wider range than the Stranded Wind focus.

One requires a good bit of carbon to make methanol :-) Right now it's done by a simple reaction using natural gas. We have filed for a patent that will permit methanol synthesis using carbon dioxide captured from ethanol plants and hydrogen produced by wind driven electrolysis but that is at bench top phase and we're hunting dollars to turn it into a pilot.

The user of nitrogen fertilizers is not optional. Or rather it is optional, but the effects of making it so are awful, as I recently covered in my shiny new contributor role on The Cutting Edge News.

Earlier this week I read about a Korean breakthrough in producing hydrogen that claims it will lower the cost of H2 as much as 20-30 times.

Dr. Sen Kim (Academician of the European Academy of Natural Science), who has been developing methods of cleaning the greenhouse gases in S&P Energy Research Institute (SPERI) since February 2008 said “Our laboratory tests show that CO2, CH4, or N2O was dissociated by low energy. We also confirmed that hydrogen (H2) and vapor(H2O) was dissociated with similar efficiency (90% or more). Traditionally hydrogen is made by electrolysis. The electrolytic method uses 4-4.5 kwh energy for getting 1 cubic meter of hydrogen. Our method uses 0.1 kwh for the same volume of hydrogen. That makes SPERI's method suitable for H2 fuel production from say, an in-home hydrogen fueling station."

Their website is:

Let's hope this is not just another wild claim.

My bullshit meter just went up to 11. If this is real we're on ammonia as a fuel just as fast as we can build these things. The site is all in Korean - do you have an English link?

Sorry for the delay in coming back on this but I have been away for a couple of days. Unfortunately I know nothing about the S&P Energy Research Institute and have no further information:-(

Do we have any Korean speakers who could shed some more light on these guys?

The entropic maximum efficiency of hydrogen dissociation (from H2O) is 83 percent @ 298 Kelvin. People who claim to get more than 83 percent are frauds.

The chemical energy (HHV) contained in a cubic meter of hydrogen gas at room temperature and 1 atmosphere pressure is about 3.5 kWh, about 1/10 the energy in a gallon of gasoline. Wouldn't it be a great universe if we could obtain that energy by investing only 0.1 kWh. But, those pesky laws of thermodynamics just keep getting in the way.

Hello Majorian
Ammonia (NH3)has a GWP of zero! not 296!
The GWP of Nitrous oxide ( N2O -Dinitrogen oxide) is 296
CO2 is by definition =1
Values fx. here:
kind regards

The nitrification of fertilizer turns NH2-->NO2(in part)due to oxygen in the atmosphere. My understanding is that 'ammonium fuel' would be burnt in the atmosphere to produce N2 gas and water--my question is how much N2 would be produced; if it would it be 1/296 or .3% of it, I would guess that we would have the same kind of problem as we have today with CO2 only with N2O.

A properly tuned engine will produce functionally no N2O. The engine would emit very little to begin with and the catalytic converter would finish off what did escape the combustion chamber.

Here's a link for feeding a ammonia-biodiesel into a Ford engine, saying that NOx emissions were within EPA guidelines, apparently using 60% ammonia and 40% biodiesel/diesel mix, any higher and more N2O would be generated.
Since 3 gallons of ammonia has the energy of 1 gallon of diesel,
that mix would have 60% of the energy of diesel.

Maybe it's something for farmers to play with.

In the abstract of the article, it does not say a 60:40 mix, it says energy replacement of up to 95%, with NOx emissions lower than biodiesel alone with energy replacement up to 60% ... at 95% energy replacement, the main role of the biodiesel is in starting the engine. AFAIU, its a two-fuel engine rather than an engine using a mixed fuel.

60:40 energy replacement at 1:3 energy by weight is about 80:20 by weight. 95:5 energy replacement at 1:3 energy by weight is about 98:2 by weight.

An interesting facet of the research reported in the abstract was success in leaving the diesel component at a constant level and varying load by varying the amount of ammonia, which would be simpler in a two-fuel engine than varying the flow of both fuels.

This seems to be a common aspect of diesel, as CNG conversions operate similarly. Diesel provides the "light off" concentration, essentially enough fuel for idle, and CNG provides demand power.

Adding water injection can lower engine temperatures too, but at the complexity expense of adding another liquid.

Would it be possible to have one tank design that could handle CNG, propane, or ammonia?

Would it be possible to have one tank design that could handle CNG, propane, or ammonia?

What is the benefit on the farm for having a tank that can handle all three? More than the problem of having the tank being able to handle any of the three is the problem of evacuating the one before filling the tank with the other.

Just thinking of the value of a true "multi-fuel" engine, where you run what's available or cheap. Ideally you wouldn't worry about evacuating the tank, and just let the computer sort out the injection volume dynamically.

Flexibility is good, but likely even if it were possible the added cost might make it non-viable.

I think this will happen for liquid fuel vehicles - Set America Free is actively pushing for flex fuel setups that will take gasoline, ethanol, or methanol. I think the flexibility at the gaseous fuel level will be a conversion thing - a CNG vehicle ought to be designed and built to take ammonia at some time in the future with a simple refit, or better yet a simple flush and refill. I don't see casual fuel alternation as a viable approach.

Another option would be a variety of "cartridge" style tanks sharing a common form factor and one or more "connector" options populated in a connector manifold. Swapping tanks might be as easy and cheap as trading out propane tanks at the hardware store, if you wanted to change fuels.

In general, it seems like diesel engines offer advantages over otto:
diesel or biodiesel (of various sorts)
- CNG, propane, or ammonia "power add"
- higher efficiency
- longer longevity

Of course, the importance of different advantages will vary for different tasks ... for transport, a high efficiency constant speed diesel engine is appealing as the on-board generator for a PHEV, while the supplemental flex-fuel is quite appealing for mechanized agriculture.

Luckily I took a while to come back, so others said it better ... a dedicated tank and an flex fuel engine would mean, for example, a member of a co-op that is ramping up production of ammonia could use a surplus amount of ammonia over what they need for their crop, and then switch to another fuel when the surplus runs out.

And of course, a flex-fuel NG / ammonia engine will also, down the track, be a flex fuel biogas / ammonia engine, so down the track that might flip over, with the co-op distributing biogas that is used for domestic uses, any surplus used to power equipment, when that runs out, switch to ammonia to power equipment, and sell surplus ammonia.

Is ammonia any better than carbon?

Nitrous oxide has 296 times the global warming potential
(GWP) of carbon dioxide.

But formation of nitrous oxide (N2O) is primarily determined by the of the combustion ... any combustion in atmosphere has ample nitrogen and oxygen supply to form some N2O and NOx (where its the N2O that is the greenhouse gas and the nitric oxide, nitrogen dioxide are the poisonous pollutants), if the heat is high enough. Since ammonia tends to burn cooler, the primary combustion products are nitrogen gas and water vapor, and control of NOx from incomplete combustion is the same basic problem as many internal combustion engines.

At 11.5 MJ/liter, it's a less efficient energy carrier than methanol at 15.6 MJ/liter.

The efficiency of any fuel as an energy carrier is a matter of far more than just the energy density. Capital intensity of the production and distribution network, for example, is not in proportion to energy density. If an ammonia distribution network already exists in a farming area, then the full capital cost for using ammonia as fuel for mechanized agriculture is lower than if a new fuel distribution network has to be established from scratch.

The wiki article on energy densities that Majorian cites appears to have an error for the volumetric energy density for ammonia. The LHV for NH3 at room temperature is actually 14.3 MJ/liter. That's ninety percent of methanol, and includes no carbon-source energy.

Including HHV ( , see Table 6), the comparison is

LHV (MJ/liter) HHV (MJ/liter)
Ammonia 14.3 17.3
Methanol 15.9 17.9

and about 25% of methanol's energy comes from converting carbon to CO2.

As for NOx, combustion of ammonia in internal combustion engines produces trace amounts of nitric oxide NO, but exceedingly small amounts of nitrous oxide N2O.

NO is straightforwardly treated with SCR, using of all things, NH3 (sometimes in the form of urea), to neutralize NO to nitrogen and water according to

4NO + 4NH3 + O2 -> 4N2 + 6H2O.

This process is routinely carried out at fossil plants and in advanced diesel engines
and . Of course, with ammonia fueled engines, the NH3 for treating NO will be readily available.

The number used by wikipedia's Energy Density Table is for LIQUID ammonia. Ammonia liquifies easily, I'd bet this is the most efficient form for its use as a transportation fuel.

and about 25% of methanol's energy comes from converting carbon to CO2.

I'm not sure what this means.

The path for ammonia creation would be
N2+3H2-->2NH3;~-47 KJ/mole (but with ammonia is that to make the reaction move forward you must be around 450 degrees C)
Water would be split by electrolysis to make H2 gas,oxygen is a byproduct.
H20-->H2 + 1/2 O2;~286 KJ/mole
Methanol would be 2 step;
C+1/2O2-->CO(exothermic) + 2H2-->CH3OH; ~-200 KJ/mole

So overall 1/2 x (3 x 286 -47)= 405 kJ/mole for NH3
or 2 x 286 - 200= 372 KJ/mole for CH3OH. These KJ/mole are enthalpy handbook values only, no entropy.

NH3:405 KJ/mole / 10 g/mole = 40.5 MJ/kg to make and 17.3 MJ/kg to burn
CH3OH:372 KJ/mole / 16 g/mole = 23.3 MJ/kg and 17.9 MJ/kg (18.6 wiki)to burn
H2O: 286 KJ/mole / 2g/mole = 143 MJ/kg (wiki gives 143MJ/kg) is the most efficient.

A lot of people don't seem to like hydrogen and want a liquid fuel.
It seems as if ammonia requires more energy invested(40.5MJ) for energy returned(17.3MJ/kg) than methanol(23.3/17.9).

I feel that in view of the current global situation of shortage of food grains, it is better to utilise the available Ammonia capacity for manufacture of fertilsers rather than using it as automotive fuel. It is a better option to directly use compressed natural gas as auto fuel instead of converting the same to Ammonia at a cost and then use Ammonia as auto fuel.

I believe you are correct in your assessment that the grain situation is critical; most of our production will be consumed by grain production for a long, long time, but we need to be discussing and moving towards ammonia as a fuel, too.

Here is a simplistic example regarding scope: Iowa has twenty seven million acres in production. Let's assume 80% is corn and that two hundred pounds of ammonia per acre (very high) is required. Following the math through yields right at a million tons of ammonia. A megawatt per year fed continuously into a Haber Bosch based plant produces a thousand tons of ammonia. Roughly one gigawatt is required to produce the ammonia needed for the crop.

Wind turbines have a capacity factor or a coefficient by which their nameplate power is multiplied to determine their actual annual yield; our winds are strong but they are not constant. We'll assume 2.5mw turbines and a 40% capacity factor, which is just a tiny but high but produces tidy math. A thousand turbines producing an average gigawatt on a continuous basis will cost about five billion dollars today and will produce the electricity required to fertilize the entire Iowa corn crop. We believe the ammonia plant cost would be in the two billion dollar range and this would be distributed to perhaps twenty sites.

Assuming a yield of two hundred bushels per acre and using the current price of $3.00/bushel the annual production from the 21,600,000 acres of corn would be 4,320,000,000 bushels with a value of $12,960,000,000. Given the twenty year lifespan of wind turbines, which are the weak link in the ammonia production infrastructure, can we service a debt of seven billion dollars over that time frame with two hundred fifty billion in revenue?

Iowa is a quarter of the nation's corn crop - multiply by four to get a national number. Solid state ammonia synthesis when commercialized will cut the energy requirements to two thirds that of Haber Bosch and plant capital costs will drop by half, reducing the needed investment to roughly four billion dollars to be charged against the same quarter trillion in revenue. I regret that I can not speak as fluently about our other grain crops.

Food for thought as well as food for the planet. Today I instigated a Congressional briefing on these topics which will happen in late February or early March. I'll be getting an assist from Bryan Lutter, a South Dakota wheat farmer, seed distributor, and TOD lurker who comments only occasionally; I've forgotten his userid but I hope he speaks up for himself.

Assuming a yield of two hundred bushels per acre and using the current price of $3.00/bushel the annual production from the 21,600,000 acres of corn would be 4,320,000,000 bushels with a value of $12,960,000,000. Given the twenty year lifespan of wind turbines, which are the weak link in the ammonia production infrastructure, can we service a debt of seven billion dollars over that time frame with two hundred fifty billion in revenue?

Umm, that's $250 billion in gross revenue for all the corn. You need to pay the capital cost of the land, the cost of planting, the cost of harvesting, the cost of transportation and some money for the farmers to get through the winter.

I don't feel like doing a few hours of research, but you're optimistic by something between a zero and a factor of three.

I never indicated that corn grew out of thin air when ammonia was sprayed from surplus C-130s that used to distribute agent orange :-) The point is that freeing the corn crop of all fossil fuel based fertilizer inputs will cost 2.8% of the total revenue. This seems a bargain to me.

And not freeing the crop from fossil fuel dependence will eventually carry a price tag substantially higher than 2.8% of the current gross revenue ... and leave the crop exposed to the risk of interruption of supply.

Planting Hairy Vetch as a winter cover crop reduces fertilizer requirements by around 107 pounds/acre of nitrogen and reduces soil erosion, waterway contamination, poor EROEI, and other problems. There are other biological methods as well including companion planting, crop rotation, biochar, crimp rollers, etc. Varyious cover crops either retain or produce nitrogen. Nitrogen fixing cover crops can in many cases eliminate the need for nitrogen fertilizer.

Producing ammonia to continue business as usual practices rather than replacing those with more sensible practices that would reduce or eliminate the need for nitrogen fertilizer is trying to solve our problems with the same thinking that created them.

Maybe we will need ammonia for some crops and occassionally for cover crop failure but the emphasis should be on eliminating or reducing ammonia requirements rather than replacing the energy source used to produce ammonia.

So how would hairy vetch be sown? The corn in July is as tall as a man and it would be unwise to run even one of the tall, skinny tired vehicles down the rows. Growth potential is suspect when the corn has already canopied. This sounds like one of those non-solutions quite popular in certain circles. Are you aware of any corn/vetch cultivation experiments? Are the results published?

Answered it myself with teh g00gle - hairy vetch is compatible with oat and rye crops and can apparently be made to work with sweet corn in small ( sun through rows?) plots. No mention of its use with field corn, soy, canola, or any other large scale crops.

Given that it works with oat and rye it would be interesting to see if it behaves well with wheat, but there are something like eighty million acres of corn for which this is not a solution.

Your 200 lb/ac figure actually comes out to about 2 million tons.  I think you meant 100 lb/ac.

-"The most promising advance in synthesis seen so far has been the development of a process called solid state ammonia synthesis (SSAS), which is conceptually an ammonia powered fuel cell being run in reverse. Energy use for this system will be two-thirds of what is required for a hydrolysis/Haber Bosch and the capital cost will be less than half."

I've often thought of a similar device that took water and carbon and produced methane. The chemistry would work out to be something like 2H2O+3C+ENERGY -> CO2+CH4.

BTW, wouldn't NOx formation be a concern if running Ammonia in a combustion regime?

I don't know of a synthesis method for methane based on what you describe but methanol seems to be fairly simple and we're pursuing that development. Liquids are much easier to handle than gasses - that whole stranded gas effect applies to production in this realm, too. Something one can simply store in a steel tank and move at will trumps something that must be compressed, networked, fiddled, etc.

Dakota gas produces SNG from coal. Multi-step process that has methanation and water gas shift reaction at some step most likely.

A chemist, George Olah, had some success a couple of years ago with a sort of methanol fuel cell in reverse. There is audio archived at NPR available here. Wasn't all that efficient as I recall.

Lest I seem ungrateful some thanks are in order to various TOD regulars.

Oilmanbob said "Why don't you build your own damned wind farm?" in response to grousing on my part last fall. Point taken and I wish he were still here to see this; he passed last December due to complications from diabetes.

NH3 noticed me and took the time to set me on this path of ammonia as a sensible product to make with wind. The formative time of the Stranded Wind Initiative is a bit fuzzy for me but I think I owe him thanks for the connection to the Ammonia Fuel Network.

The thing that makes my memories of last summer through this spring fuzzy nearly killed me at the end of February and would likely have finished me or at the very least left me disabled had it not been for the timely assistance of AlanfromBigEasy on two separate occasions. That I am alive, well, and threatening the traditional ammonia synthesis business with my antics is entirely due to his kindness.

Jerome a Paris has made a phone call or two and sent a couple of emails, without which none of this would be happening.

The Leanan and the Drum Beat regulars should all point with pride to my progress - I knew beans about energy when I showed up here last summer. If I manage to sound knowledgeable on certain points it is the schooling (and occasional drubbing) they administered in daily discussion which got me there.

Another fascinating conference coming up this week, The 6th Annual Methanol Forum in Dubai:
PDF file:

Any chance someone will be there to report back on how it went?

The age of manufactured fuels is coming. The raw materials are hydrogen, carbon and sunshine, 3 of the most common ingregients in our solar system and on our planet.


I had a nice talk with the CEO of Methanex at the recent Set America Free conference. I've just dropped him a note to see if I can interview their person who attended. I make no promises but if I get access I'll write it up for TOD.

The problem about all this is the abysmally low efficiency of haber bosch, and getting 2/3 of it still won't cut it, even without considering the inefficiency of fuel cells or heat engines.

For stationary energy storage, you'd get better efficiency with electricity-heat-electricity and you can't beat those low capital costs.

For a mobile app, it's batteries and maybe some biofuels. Ammonia is a very silly fuel from an exergy perspective. Even hydrogen is better and that says it all.

I understand that the biggest problem with H2 is storage: low volumetric energy density, thermodynamic losses in compression / decompression or liquefaction, danger of extremely high pressure storage. IIRC, liquified ammonia (like propane, happens at low pressure) has a higher volumetric hydrogen content than liquid H2, but without the obvious practical problems attached to liquid H2.

The biggest problem is efficiency, because it can't compete with it's own energy source, as Bossel puts it. It's not very interesting to solve the storage problem if the macro-economics are unfavorable by thermodynamics (or entropy, if you will).

Storage and high capital costs are problems for hydrogen right now, but even if they were solved eventually, there still is that efficiency gap, very big even at the thermodynamic limit. That means we have to do with a much larger energy demand. Quite unacceptable when better alternatives are available.

Ammonia might be used to substitute biofuels (where batteries might not be practical) as a more likely candidate than pure hydrogen. Maybe.

Ammonia might be used to substitute biofuels (where batteries might not be practical) as a more likely candidate than pure hydrogen. Maybe.

AFAIU, the three biggest fossil fuel energy sinks are transport, residential, and agriculture. Ammonia fuel for the first two does not seem all that promising, but in the third, far more so.

Mechanized agriculture is precisely an area where batteries are at present not tremendously practical ... and ammonia seems much more practical than H2.

I myself am skeptical about the long-term sustainability of anything like the current agricultural system, even if power entirely from renewable sources. However, that is the agricultural system we have at present, and a transition to a more sustainable system without famine at some point along the way would seem to require bridging technologies that can keep the existing system running while alternatives ramp up. As a bridge technology, this ammonia option seems very promising to me.

Here in New England Central Boiler outdoor supplemental heat is very popular. They make models that run on wood, gasifiers for split, seasoned hardwood, pellet boilers, and some models are dual fuel. I'd really like to see a pellet/ammonia system tested somewhere. If they unit is outdoors thusly protecting the home owner from the inhalation hazard of a leak and a sensible cutoff valve is in place ammonia would be little different than propane for heat.

H2 will burst into flame at concentrations between 4% and 75%, it is only a little nicer to metal than loose neutrons from a nuclear reactor, and it's a relentless escape artist.

The little ammonia nurse tank has more hydrogen in it than the big hydrogen tanker.

Even liquid water has more hydrogen atoms than liquid hydrogen. Interesting, no?

Low volumetric energy density is nasty, because it magnifies all sorts of parasitic losses. Ammonia deals with most of this problem, but requires breakthroughs in production cost and energy use. The presentations assume very optimistic long term production costs. Like $ 350/kW electrolysers. I'm not saying that won't happen, eventually, but if they're going to assume all kinds of learning effects on hydrogen/ammonia then why not with competitors like batteries, algae biofuels etc.? This is all at odds with each other. Hardly an objective assessment. Typical salesmen speech. But there's a lot of good information otherwise so they may be excused for that.

I agree with your comments. Low volumetric energy densitiy surely hurts prospects of using hydrogen, either liquid or pressurized.

I also agree that some of the assumptions and estimates concerning ammonia production are a bit rosy, or more than a bit. Although from what I've been able to discern, SSAS doesn't use electrolyzers, so there may be opportunity there.

And, I finally agree with that it shouldn't be ammonia vs. other alternatives, it should be "and" other alternatives, and hopefully the more "flexy" the better.

I just wondered.

How small can those SSAS be made?

The market for off-grid applications is more interesting for the short term.

A combination of batteries (for the flutuation of the day) with hydrogen for times without sun or wind, is currently the cheapest solution for closed loop system. But still, for a decent amount of hydrogen, you already need a large tank. With ammonia, that tank would be much smaller.


I keep asking what the lower bound for a Haber Bosch plant is and I keep not getting an answer :-( The lower bound for a SSAS plant is a single tube - the synthesis tubes look sort of like a thick fluorescent light bulb. I forget the daily output but it's not very much at all. That is incredibly exciting for farmers, who are very interested in single wind turbine solutions for their farms. I suspect the batch mode process briefly described above is also going to be of interest, but until each has been put through pilot phase we're left waving hands and theorizing :-(

I'm very happy to see that Australia was able to send a representative. I hope there is fruitful further exchange as a result.


They already have a Australian commercial partner - Wizard Power. They're seeking a commercial partner here who can "win business". We're interested at Third Mode Energy, the commercial spin off from the Stranded Wind Initiative that is dedicated to renewable ammonia, but with just three of us we're not of the caliber they need.

If someone reading this represents an engineering firm that can close utility scale business I'd be happy to share contact information. Take my TOD userid's initials as my email address and it's at the Stranded Wind domain.

if we could identify a source of funding for the estimated $800,000 needed to bring the technology to pilot stage

It's sad that projects like this cant get funding. That amount is equal to approximately 15 seconds of Pentagon funding. 15 seconds!