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THE Ammonia Fuel/Energy Storage Thread

Discussions of conventional and alternative energy production technologies.

THE Ammonia Fuel/Energy Storage Thread

Unread postby EnergySpin » Fri 05 Aug 2005, 02:08:33

Time to look from Hydrogen from another viewpoint

I was reading through the RISO report on hydrogen economy, and this report (more than 1 year old) examined different ways of storing hydrogen.
In the chapter : Hydrogen system energy technologies in global, European and Danish perspective :
Instead of molecular hydrogen (H2), substances known
as hydrogen carriers might be more effective as energy
vectors. Potential carriers are hydrocarbons, ammonia
(NH3) and methanol (CH3OH)
. All these substances are
already produced and handled in large quantities, so
they have the considerable advantage that a suitable
infrastructure is already in place. Hydrocarbons are the
most effective hydrogen carriers known, and they can be
produced in a CO2-neutral manner using water, CO2 and
energy as the raw materials

Hm chemical storage vehicles of hydrogen? How dow the compare to other fuels? Lets consider the following heat capacity data of various fuels:
Hydrogen (pure) 61000 btu/lb
gasoline (cars) 20400 btu/lb
gasoline (aviat) 18110 btu/lb
methanol 10258 btu/lb
ammonia 9667 btu/lb
wood 6500 btu/lb
hydrazine (space shuttle fuel) 8345 btu/lb
Historical sidenote: industrial methanol and ammonia synthesis did not rely on natural gas feedstocks but by electrolyzing water and combining it with atmospheric CO2 or Nitrogen

The funny thing is that a significant infrastructure exists for ammonia and methanol distribution and that both these fuels can be used in ICEs (as well as fuel cells). Even though their specific combustion heat is approximately half the one specific heat of gasoline, they do not require the expensive storage that hydrogen requires (in fact they are stable under storage for months).
The advantages (especially of NH3) were detailed on 2 journals. First one was in Mechanical Engineering 2 years ago (click me) and the second one was a letter send to Physics Today last month by Peter J. Feibelman (can be read here)
Even though there are some toxicities associated with ammonia
1) it is not flammable as hydrogen is, and can be stored in liquid form at 8 bar (contrast that with the 250 bar of presurized hydrogen storage)
2) It is not a greenhouse gas
3) it burns cleanly to nitrogen and water
4) leaks can be detected by our noses at 1/5000 the toxic level (any of you who has worked with ammonia in a lab can testify to that)
5) An ICE design (actually similar to the one used in cars today) has been designed by Sandia National Laboratories (read here)

why aren't people discussing this low technology solution to a liquid fuel problem? Granted electricity generation capacity will be needed ... but the electricity generation capacity IS NOT our problem ... nukes (even though people dislike them,) big and small hydro and wind can more than double electricity generation capacity.
Since people might have discussed this H2 storage before, I hope you could shed a light why this route is not pursued. For example the original Physics Today Letter on the hydrogen economy (read here) never mentioned ammonia and methanol as storage mediums for a "hydrogen economy" (but to be fair ammonia appears in Figure 4 where different high tech hydrogen storage media were considered). What is also interesting is the answer that Crabtree, Dresselhaus and Buchanan gave Feibelman about ammonia:
Peter Feibelman raises a good point in advocating NH3 as a hydrogen storage medium. He points out many advantages, including its high storage capacity, the significant ammonia infrastructure already in place, and our extensive chemical knowledge and industrial experience with ammonia.

The problem of effective hydrogen storage is one of the most challenging in the hydrogen economy, and we should pursue all promising options. The use of ammonia in a hydrogen economy has been discussed since at least the 1970s; Ali T-Raissi summarizes its history and its possibilities.1 The subject remains vibrant today; new mechanisms for the release of hydrogen from ammonia over catalysts at acceptable temperatures are continuing topics of research.2 A major challenge is toxicity, as Feibelman points out, but all hydrogen storage proposals come with safety issues.

Ammonia can be used effectively in other hydrogen storage media as well,1,3 notably in combination with its borane analog, BH3. NH3BH3 releases more than 12% of its mass as H2 in decomposing to NHBH at low temperature and ambient pressure. Its release rate and decomposition chemistry can be significantly improved by nanoscale structuring in porous hosts.3 This example shows how the richness of hydrogen chemistry and the influence of nano-patterning lead to new horizons in hydrogen storage.

They totally evaded the question, even though in their original article about the hydrogen economy they identified the following targets for a hydrogen economy:
The two challenges for on−vehicle hydrogen storage and use are capacity and cycling performance under the accessible on−board conditions of 0−100°C and 1−10 bars.

BTW these conditions are achievable today with methanol and ammonia without an Apollo type of project.
Ali T-Raissi wrote about the ammonia prospect in the Proceedings of the 2002 U.S. DOE Hydrogen Program Review. Reading that report was hilarious ... work on the subject was done 35 years ago:
The use of ammonia as chemical hydrogen storage compound that can be easily dissociated and used in the fuel cells and power plants is not new and has been ongoing for more than 40 years [1-58]. In the early 1970s when the concept of "Hydrogen Energy Economy" was widely debated, it was envisioned that ammonia (NH3) would provide a perfect storage medium for hydrogen produced by the ocean thermal energy conversion (OTEC) plantships [16,32]. In the early 1980s, Strickland at the Brookhaven National Laboratory (BNL) conducted a systems study to determine the economic prospects of using anhydrous liquid ammonia, produced by OTEC, as a hydrogen carrier for annual H2 demand of 10-100 million standard cubic feet [28,31]. BNL study showed that OTEC NH3 was competitive with H2 made at the point of use via water electrolysis, steam reforming of natural gas, or OTEC liquid hydrogen (LH2), in the upper fifth of the use range. In another BNL study, three alternative transportation fuels (ATFs) were compared with respect to the input energy required for their production from NG, their H2 storage capacity and cost per unit of energy contained ($/million BTU)[26]. The ATFs chosen were LH2, hydrogen produced by steam reformation of methanol (MeOH), and H2 generated via thermocatalytic dissociation of anhydrous liquid ammonia. The BNL results showed that anhydrous liquid ammonia had considerable advantage over MeOH and LH2, coming very close to matching gasoline performance as a motor fuel.


It gets even better in the next paragraph .....
As the 1980s drew to close and with the demise of non-fossil hydrogen production technologies as a near-term reality, ammonia disappeared as a viable hydrogen storage medium from the U.S. DOE programs [57]. The commonly held view was that OTEC would be roughly twice as expensive as the conventional energy forms due to the high capital cost of OTEC plants made under existing designs at that time. It is often stated that a $40/barrel oil cost would be necessary to spur investors into seriously considering OTEC technology [58]. The total energy efficiency is lower with ammonia as the H2 carrier compared to methanol. Therefore, if methane is used as the primary fuel, then methanol will likely be the liquid fuel of choice for fuel cells, especially PEMFCs. Presently, the DOE fuel cell for transportation program appears to be focused on the use of fossil fuels and for that reason ammonia is not generally considered as a viable H2 carrier. [smilie=eusa_wall.gif] The ammonia scenario was unique to the OTEC project, where the electrical energy would be generated at a remote location and it was not feasible to install either power lines or a hydrogen pipeline to the shore. Hydrogen production and subsequent conversion to NH3 for shipment to the shore seemed to be the most attractive way to store and transport OTEC hydrogen. Using ammonia directly in the fuel cells then appeared to be the most plausible approach. In other words, in the case of solar/renewable hydrogen production, ammonia can still be viewed as a viable chemical storage medium for supplying hydrogen to fuel cells, especially AFCs.
(AFC = Acid Fuel Cell)

Another beauty from the same report:
....Much effort has been expended to develop steam reformation of methanol as a process for generating hydrogen for use in fuel cells. Nonetheless, a comparison of the economics of H2 production via ammonia decomposition for alkaline fuel cells versus methanol reformation for acid fuel cells has shown that ammonia decomposition is economically more favorable [40,41,55]....

Regarding the health effects of the ammonia it is true that it is a toxic compound as well as any of the other fuels (i.e. methanol) and even gasoline fume but maybe there is another reason why ammonia (besides the obvious (in bold in a previous section).
For example, anhydrous ammonia is used, extensively, in the manufacture of illicit drug methamphetamine. Anhydrous NH3 is used in the so-called "Nazi method" to spur methamphetamine production [83]. This method does not require extensive knowledge of chemistry, uses no heat, and is much simpler technique than the ephedrine-pseudoephedrine reduction or "Red P" method that is also used for producing methamphetamine. Due to these and other considerations, it appears unlikely that NH3 will find widespread use as a high-density chemical carrier for H2 in the future transportation applications. This is despite the fact that ammonia is a superb fuel for power plants, in general, and fuel cells, in particular. Furthermore, due to economic and energy efficiency considerations, it will be advantageous if a method could be found that completely eliminated the need for or greatly simplified the function of the on-board NH3 reformer. One approach to mitigate ammonia's shortcomings is to complex NH3 with other hydrides so that the resulting compound is stable but not toxic or cryogenic. The prospective process must produce a compound that contains H2 at gravimetric and volumetric densities comparable to that of anhydrous ammonia. A class of compounds (with generalized formula BxNxHy) known as amine-boranes and some of their derivatives satisfy this requirement.

Any thoughts? Simple chemicals which do not rely on massive infrastructure and can burn in regular ICEs have been available since the 70s (If I'm not mistaken, there was an ammonia steam engine running in 19th century France). Storage becomes much less of an issue with these fuels, which are stable over months. Energy content is half of gasoline but they can be transported cheaply without the hurdles of liquid H2.

Collin Campbell himself mentions the generation of NH3 as a hydrogen carrier in an interview he gave 3 years ago in a FEASTA conference in Ireland (even though he never mentioned the fact that the bona fide Haber process i.e. the catalytic reaction of N2 and H2 IS NOT DEPENDENT ON FOSSIL FUELS)
I know of one project of trying to glass over the stony desert of Australia which has very high solar radiation, use this solar electricity to electrolyse water, with which to make hydrogen, and then from the hydrogen use coal there to transform this into ammonia and methanol which are easier to transport than hydrogen itself. So you ship this ammonia and nitrogen to Europe and then re-form it back into hydrogen. But this whole interest in hydrogen is primarily from a climatic standpoint, and I don't think it has particular meaning in relation to energy supply itself. Certainly hydrogen a desirable thing from a climatic standpoint, an emissions standpoint, but you've got to make the stuff in the first place. And a supply of ordinary natural gas will run a fuel cell perfectly well. There is this idea of a fuel cell under the stairs in everybody's house, you know, that would give heat and electricity and so on. So there are solutions in that direction too.


The whole NH3 issue becomes even more interesting ... when one consideres that the at least one university has looked into ammonia as a fuel and have generated some pretty interesting numbers regarding the infrastructure needed to provide the US with ammonia fuel. Specifically Iowa Energy Research Center held a meeting on 10/28/2004 about Ammonia, a Solution to the Hydrogen Challenge?
On the presentation entitled Ammonia as transportation fuel
Olson :
- he compares NH3 to other carriers of energy(p33)
- compares the cost of NH3 to gasoline (gas was $1.5 per gal back then) and he lists the following numbers: NH3: 10-14.86$/MMBTU when gasoline was $10.52-13.55/MMBTU and ethanol : $16.44/MMBTU!
- examines the delivery infrastructure in the US p38
- industrial safety p40 (safer than gasoline)
- and the economic impacts (Attention : Data are from 2003)
Current Imports: ~ 13 million bpd
= $114 billion/year @ $24/bbl, $228 billion @ $48/bbl
2003 Gasoline Consumption – 8,756,000 bbl/day
15.3 x 1015 Btu/year = 850 million ton/year ammonia
1250 new plants @ 650,000 ton/year each
$562 billion investment @$450 million/plant
375,000 new jobs
$5 billion new tax revenue/year (employees only)

In the same conference issues pertaining to ammonia as a fuel in ICE were discussed by Ted Hollinger (Internal Combustions And Ammonia) who gave a presentation of a resurrected 4.9L Ford Engine resurrected from the dead and fitted to run on ammonia 8O

In summary it appears that there exists a low technology liquid fuel which:
- could be implemented much easier than the "Hydrogen economy" (even though it is a hydrogen carrier) using existing chemical plant designs and chemical processes that are 100 years old
- has a distribution infrastructure in place in the rural US but can also be carried (by trucks) in the cities.
- can be synthesized both from existing fossil fuel feedstock but most importantly from "reneawable" electricity (wind, concentrated solar ), water+air
- can be burnt in both existing (ICE) and emerging (custom ICE, fuel cells) engine platforms with characteristics similar to gasoline
If all those features are real (and both the industry and DOE scientists have attested to that) why do we keep pushing the "hydrogen" economy with all the expensive infrastructure, proprietary technology and insurmountable transportation and storage issues.
I need some time to digest these and will probably email Feibelman but this is so interesting.
PS If people have already discussed this issue... disregard it after providing me with a link :)
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Unread postby Caoimhan » Fri 05 Aug 2005, 12:11:39

This is very interesting...

Can NH3 be mixed with other fuels? One of the arguments against E100 (100% Ethanol) is that people may decide to drink it. I think it's funny that an argument against NH3 is that it can be used to make methamphetamine. And we don't allow the growing of industrial hemp in the U.S., because it's too much like marijuana? (And industrial hemp could be a great source of cellulose for ethanol production).

What else is the "war on drugs" going to cost us?

I guess the CIA's black budget is more important than our energy security.
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Unread postby EnergySpin » Fri 05 Aug 2005, 13:57:50

Caoimhan wrote:This is very interesting...

Can NH3 be mixed with other fuels? One of the arguments against E100 (100% Ethanol) is that people may decide to drink it. I think it's funny that an argument against NH3 is that it can be used to make methamphetamine. And we don't allow the growing of industrial hemp in the U.S., because it's too much like marijuana? (And industrial hemp could be a great source of cellulose for ethanol production).

What else is the "war on drugs" going to cost us?

I guess the CIA's black budget is more important than our energy security.

I have no freaking idea (I'm a poor MD not a fuel expert)... the Advanced Internal Combustion Engine project alluded that mixtures may be possible.
I was checking the Chemical Engineering literature. People have produced low temperature designs that can generate ammonia via electrochemistry bypassing the Haber step, allowing even decentralized generation. I will try and post relevant literature but it is amazing .... with the exception of health side effects (which can be dealt with and prevented) and work only on vehicular storage tanks ammonia seems a much better alternative that metal hydrides. It seems that the expensive route is being pursued ... nanotech and all the crap. Maybe this has someting with maintenance of control over fuel supplies. I guess that certain people would not be happy if liquid fuel generation was possible from (renewable) electricity AIR and WATER. The electricity infrastructure would be the bottle neck ... but a nice concentrator solar facility could do that locally (and even be part of the ammonia plant)
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Unread postby Caoimhan » Fri 05 Aug 2005, 14:17:01

Can you provide links to this process? I'd definitely be interested in learning more about it.
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Unread postby EnergySpin » Fri 05 Aug 2005, 14:32:45

Caoimhan wrote:Can you provide links to this process? I'd definitely be interested in learning more about it.

The electrochemical you mean? I will try to locate something more "scientifc" but the links in the original response (especially the letter to Physics Today) have a couple of articles and links. Regarding less energy intensive measures I will do so over the next couple of days (I'm in the process of moving and things are a litl bit crazy around here :) ). I suggest following the conversation between the people from the National Labs in Physics Today.
Feibelman never got a satisfactory answer (and neither did I). The RISO report also shows that the Europeans are not willing to follow a reneable energy path to hydrogen. Supposedly this was a report on renewable energy technology which never really adressed non-renewable ways of creating hydrogen (with the exception of the paragraph I quoted). It was all about generation of hydrogen from non-renewable sources (like natural gas, biomethane) and various blue sky research wishful thinking on storage (nanocarbon cages, metal hydrides etc). IMHO the players are looking for a way to burn ALL the stuff beneath the ground and create a really expensive infrastructure to maintain control over future fuel supplies (and I'm not a conspiracy person). To prevent delirious thinking I will stop here and turn to the literature for data
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Unread postby Caoimhan » Fri 05 Aug 2005, 14:47:53

Yeah, I'd like to know how to produce ammonia from electricity, air and water. Is it something that could be built by a do-it-yourselfer?
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Unread postby EnergySpin » Fri 05 Aug 2005, 15:03:04

Caoimhan wrote:Yeah, I'd like to know how to produce ammonia from electricity, air and water. Is it something that could be built by a do-it-yourselfer?

Dont think there exist DIY projects yet ... but ammonia was synthesized this way for the greater part of the 20th century. The use of natural gas feedstocks is relative new. The Haber process (final step N2+H2->NH3 +1/2 H2) takes place in 500oC with an iron catalyst .. so this is not the way to do it at home :)
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Unread postby strider3700 » Fri 05 Aug 2005, 16:09:16

http://designer-drugs.com/pte/12.162.18 ... monia.html

A quick glance tells me that I don't want to be doing this at home ;)
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Unread postby Devil » Sat 06 Aug 2005, 05:07:41

How much energy is requiredd to make NH3? If used in a fuel cell, how much energy is required to split it again to feed the H2 to a fuel cell? What is the holistic EROEI? Maybe 0.1???

In an IC engine, what are you going to do with all the toxic NOxs generated?

Then consider, NH3 has a MW of 10, only 30% of which is potentially energy producing, the other 70% being ± inert. That means your fuel tank has to be so much larger to store a given amount of energy.

However, NH3 can be a precursor for some quite interesting explosives, for the benefit of AQ and Co. The ACGIH recommend a time-weighted average threshold limit value of 25 ppm, which would be very difficult to maintain for those working in a filling station. Worse, the acute toxicity is high because the pH of body fluids exposed to an accidental heavy dose can easily exceed 10, which is corrosive to human tissue. Can you imagine what could happen if an NH3-fuelled vehicle had a fuel-pipe broken or, worse, an accident ruptured the tank?

Another problem is that NH3 is extremely hygroscopic, so that any exposure to air will react with the humidity to form NH4OH. The presence of that may upset the energy-producing properties. A leak can cause damage to vegetation, nearby water courses and animals. For this reason, there are strict regulations for handling NH3, which is sometimes used as a neat fertiliser. Google ammonia accident to see the results of accidental leaks, some of them quite small. For handling ammonia, see http://ianrpubs.unl.edu/safety/ec738.htm. Guess we would have to wear chemical-protection goggles and other PPE when driving an NH3 car!

Then do not underestimate the toxicity of NH3.
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Unread postby EnergySpin » Sat 06 Aug 2005, 14:34:24

Devil wrote:How much energy is requiredd to make NH3? If used in a fuel cell, how much energy is required to split it again to feed the H2 to a fuel cell? What is the holistic EROEI? Maybe 0.1???

In an IC engine, what are you going to do with all the toxic NOxs generated?

Then consider, NH3 has a MW of 10, only 30% of which is potentially energy producing, the other 70% being ± inert. That means your fuel tank has to be so much larger to store a given amount of energy.

However, NH3 can be a precursor for some quite interesting explosives, for the benefit of AQ and Co. The ACGIH recommend a time-weighted average threshold limit value of 25 ppm, which would be very difficult to maintain for those working in a filling station. Worse, the acute toxicity is high because the pH of body fluids exposed to an accidental heavy dose can easily exceed 10, which is corrosive to human tissue. Can you imagine what could happen if an NH3-fuelled vehicle had a fuel-pipe broken or, worse, an accident ruptured the tank?

Another problem is that NH3 is extremely hygroscopic, so that any exposure to air will react with the humidity to form NH4OH. The presence of that may upset the energy-producing properties. A leak can cause damage to vegetation, nearby water courses and animals. For this reason, there are strict regulations for handling NH3, which is sometimes used as a neat fertiliser. Google ammonia accident to see the results of accidental leaks, some of them quite small. For handling ammonia, see http://ianrpubs.unl.edu/safety/ec738.htm. Guess we would have to wear chemical-protection goggles and other PPE when driving an NH3 car!

Then do not underestimate the toxicity of NH3.

Starting backwards a few general comments
I do not underestimate the toxicity Devil ... as I said it MIGHT be a vehicle for the hydrogen economy given its storage advantages over pure hydrogen. I was going to start another thread on methanol (the other small molecular hydrogen carrier) to see if the hydrogen research programs are (deliberately?) overlooking solutions that might be technically easier for a hydrogen economy (IF THE PUBLIC AGREES THAT SUCH A HYDROGEN ECONOMY IS NEEDED). Part of that exercise would be to compound the initial thread with realistic data on safety issues. For example the metal hydride option which people seem to be pursuing is not exactly human friendly. The majority of the heavy metals have well defined and insidious ill-effects on human health and require extensive mining (environmental destruction) but yet a holistic assessment is never made.

General Safety Issues:
To reduce toxicity for storage research will be needed in tank design (I think even that letter in Physics Today said that), but hydrogen (or methanol for that matter) are not less dangerous (factoring the dangers of flammability and exposure toxicity). Regarding the leak, I'm not sure that vegetation is going to be damaged, but animals (and humans) will through skin and respiratory tract exposure.
In addition ammonia was used in home refrigeration years ago and is still used massively in industrial refrigeration and I have not seen employees at KMarts wearing masks (granted handnling of ammonia during transportation requires such measures).
And the same arguments that you made for ammonia (i.e. it can be used in dangerous chemicals or explosives) can be made for methanol (excellent solvent, clearly defined toxicity when consumed and upon exposure), gasoline, hydrogen. For example my assessment of the dangers of methanol is that it exceeds the dangers of ammonia because it is not detectable by the human senses (ammonia is detectable at concentrations as low as 5ppm) and that people will have a huge financial incentive to use it for illicit booze distillation. When it comes to risk-benefit I suppose you know that all interventions are judged based on the relative benefits vs dangers. The fact that in the Us (and increasingly in Europe) the majority of homes are sitting on a bomb (gas distribution networks) which could potentially lead to deaths (due to explosions, asphyxiation) has not been a particularly strong deterrent to the use of natural gas even though a competitor (i.e. electric heating) might be safer by a factor of 10 or 100.

Going to energy-storage issues:
Starting from electrolysis : one needs 4KWH of electricity to produce 3 KWH of hydrogen from ammonia (this is still an energy carrier, we have to remember that) and this is the energetically expensive step (shared by ammonia and pure hydrogen) so this gives an EROEI of about 0.75

Ammonia synthesis and storage does require two extra steps (extraction of nitrogen from air and the Haber step). The DOE which did look into such matters (in the context of the OTEC program) made the following estimates (btw I cannot find the data from Norsk Hydro which did synthesisze ammonia from electricity till the 80s, so I would appreciate your input if you happen to have access to them):
- a plant with electric generating capacity of 365MW would produce 1100 metric tons a day which is equivalent to 150000 gals gasoline. One gal of gasoline gives 125000 BTU and one million BTUs are equivalent to .293 Mwh. Therefore the energy balance is
Energy In 365 x 24 = 8760 MWh
Energy Out = 150000 x 125000 x 0.293/1000000 MWh = 5493.75 MWh

EROEI = 5493.75/8760 = 0.627
The reason that that these figures is close is because the catalytic combination of N2 and H2 is an energetically cheap reaction. The actual figure is 0.5KWh per kgr of NH3 synthesized by the High Temperature High Pressure Haber method (figure taken from the Royal Swedish Academy of Sciences Nobel Prize Presentation speech in 1918, which can be read online at http://nobelprize.org/chemistry/laureat ... press.html )

That's a loss of about 10% compared to hydrogen generation, but if you factor in loss of hydrogen from tanks at a rate of 1.7%/day then you can interrogate the exponential formula and see that the two fuels become roughle equivalent after 10 days of storage and after that NH3 becomes the energy winner.


2.2 gal of NH3 = 1 gal of gasoline in terms of energy (BTU/gal) when burnt in ICEs (you can verify that with the link to the PDF in my first post, as well check it against any decent chemistry book) and it can be stored under pressure temperature conditions that are more favourable for the hydrogen (and it will not leak through the tanks like hydrogen will). That means that the tank has to be less heavy than the corresponding one needed for pure hydrogen storage. So the net vehicular weight (fuel+tank) will likely be in favour of ammonia or methanol or other such carriers.The same publication I referred to, did address catalytic reduction of nitric oxides via zeolites btw.
Regarding the use of ammonia in electrolytic cells, I think I have provided more than enough links for the interested reader to follow (including the Iowa conference), but I will extract the number from page 4 of the Ali T Raissi report : 16% of the energy stored in ammonia will be needed to break the ammonia in a electrolytic cell. You can plug in this number and see why an ICE or a fuel cell are both more viable as options compared to a "pure hydrogen" future from an energy in energy out perspective (IMHO)

Vehicular safety:
Would you agree that during collisions, accidents the probability of an adverse outcome from the fuel tank itself is approximately proportional to the Probability(explosion) x Probability(leak) (technically speaking I should be using conditional probabilities of harm here since not al leaks and not all explosions will result in death or harm). Ammonia might balance the two dangers so the net result might be comparable to gasoline but I cannot provide more data to that and neither can you or anyone else till someone decides to do test this hypothesis or do the engineering.


Delivery of ammonia:
At least here in the US (cannot say about the rest of the world), the distribution network is extremely safe, but then again workers are required to go through retraining every 3 years. Accidents do happen and none of them were lethal. Regarding the limit , I do not know where you get your estimate that a limit of 25 ppm will be difficult to maintain when such limits ARE already maintained in chemical plants where ammonia is produced (and there the potential exposure is potentially in high temperature , high pressure settings). No one is full enough to go and suck NH3 for dynamite (except maybe the lunnies in Idaho) in spite of the easy access to the stuff (check the ammonia pipeline in the US)

Environmental Impacts:
The Environmental Handbook of the German Federal Ministry for Economic Cooperation and Development has an extremely detailed section on the impact of industrial scale ammonia generation using a variety of methods including water electrolysis. The relevant section can be read here
In normal operation, the plant does not release any pollutants into the environment. The continuously formed waste gas streams are processed internally or in the synthesis gas production plant.

No problems arise with the disposal of the catalyst, consisting of iron with small quantities of Al2O3, K2O, MgO, CaO and SiO2, an operation which takes place at intervals of around 5 to 10 years (e.g. smelting, road-building).
which should be contrasted to the hydrocarbon method:
Waste gases

- Carbon dioxide (CO2):

It occurs at a concentration of around 98.5 % by volume, is used in full or in part as a raw material for urea synthesis and can be released into the atmosphere untreated as in practice the only impurities contained are H2, N2 and CH4.

- Flue gases from the primary reformer and steam boilers:

If the heating medium contains too much sulphur, it may undergo a purification process to keep SO2 values in the flue gases to within admissible levels. Primary measures to reduce the NOx emission can be taken in the primary reformer. Flue gases are released into the atmosphere through a chimney so as to comply with the values of the TA-Luft [Technical Instructions on Air Quality Control] valid in Germany, for example.

- Other waste gases:

All other waste gases formed in the plant contain combustible components and are fed into the plant’s heating gas system. If there is any unscheduled stoppage, process gases (H2, CH4, CO, CO2, NH3, N2, steam) have to be burnt in a flare as a temporary measure so that only flue gases are released into the atmosphere.


Financial aspects:
Cheap natural gas is the only reason that the electrolytic method is not used any more (even though the Norwegians kept it till the the late 80s) for fertilizer use today. If renewables really take off (and the wind and solar potential is there) ammonia might be one reasonable way of storing electricity (or at least utilizing the output of wind farms when it exceeds the demand) . My personal opinion to that (and this is a point where more educated people should jump in) has to do with the existing large scale infrastructure and knowledge of building and operating ammonia storage plants. Being a personal non-expert opinion I expect (hope) to be challenged by data.


To summarize:
IMHO NH3 seems (at a first glance) a more viable option for kickstarting a H2 future if this is ever to materialize. Initial infrastructure, trasportation and storage issues are much much easier to solve compared to a hydrogen stored in metal hydrides. Health issues related to storage and transportation have to be adressed ... but in terms of safety ammonia distribution seems to be much safer than the holy grail of nuclear industry or even domestic natural gas when the different size is accounted for. Since at personal level I'm willing to take the nuclear risk (hell there are a few nuclear reactors closeby) and I use natural gas I'm at least as willing to have engineers look into this seamingly more benigh option parallel to with other options. I think I have used a sufficient number of conditionals in my assessment to make it rather clear that a holistic assessment (craddle to grave) will be required. And no I do not think that it is viable to replace the gasoline extravaganza which allowed personal transportation but it might be a better liquid fuel than pure hydrogen. In addition it might be the single most viable option for renewable electricity storage in regions that do not have access to hypsometric differences to build pump hydro plants (inspite of the 20% loss of storage capacity compared to pump hydro plants)
Last edited by EnergySpin on Mon 08 Aug 2005, 17:31:51, edited 1 time in total.
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Unread postby Dezakin » Sat 06 Aug 2005, 18:27:08

How is this better than synthesizing diesel fuel or methanol if you're addicted to the fuel cell hype.

Everyone has a favorite alternative chemical fuel, from elemental boron, flourines, chlorines, and my favorite, hydroboranes.

Hydroboranes are synthesizable liquid fuels that were considered by the US air force because they have more than twice the volumetric energy density of kerosene and they wanted to be able to bomb the soviets without having to refuel. Runs into little issues of course, like boron oxide gumming up most engines with viscous crap, being expensive to synthesize and my favorite, it has the annoying behavior of degrading into a sort of low grade nerve gas.
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Unread postby EnergySpin » Sat 06 Aug 2005, 18:42:18

Dezakin wrote:How is this better than synthesizing diesel fuel or methanol if you're addicted to the fuel cell hype.

Everyone has a favorite alternative chemical fuel, from elemental boron, flourines, chlorines, and my favorite, hydroboranes.

Hydroboranes are synthesizable liquid fuels that were considered by the US air force because they have more than twice the volumetric energy density of kerosene and they wanted to be able to bomb the soviets without having to refuel. Runs into little issues of course, like boron oxide gumming up most engines with viscous crap, being expensive to synthesize and my favorite, it has the annoying behavior of degrading into a sort of low grade nerve gas.


Good question ... regarding fuel cells (taken from my first post) The BNL results showed that anhydrous liquid ammonia had considerable advantage over MeOH and LH2, coming very close to matching gasoline performance as a motor fuel.
Boronated ammonia analogues were examined by the DOE report (Raisi paper) and did some analysis of the Boron scarcity issue.
Ammonia has a few advantages: it can be synthesiszed from "clean" sources like nitrogen and water and (renewable) electricity and it does not interfere with the carbon cycle.
The fact that DOE and industry have looked into ICE and fuel cell designs (in fact it can be used in alkaline and acidic fuel cells, offering lots of research opportunities) gives you an idea of the versatility of this compound. In addition ... (and unlike the boronates) we have a pretty good understanding of the biological mechanisms of nitrogen fixation and at least a shot in bioengineering something that can produce it with minimal intervention. Having said all that and since there are no free lunches in this world .... the toxicities are there but the challenges seem to be manageable compared to hydrogen.
My own view: it has a higher chance of smoothing the transition away of fossil fuels which is needed anyway due to climate change. In addition we should make provisions for an ammonia generation for agriculture when cheap natural gas is no longer with us. But of course this means electricity from both nuclear and renewables
Historical note: Carter wanted to switch the transportation to ammonia in the 70s. That was the intent of the Oceanic Thermal program ... shot down by RR.
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Unread postby Oily_Bill » Mon 08 Aug 2005, 04:57:55

ESpin,

Wanted to offer my support and congratulations to your research on this. Having been lurking on this board for over a year, this seems the most promising possibility I have seen.

Can be made from Renewable electricity
Energy density in the same ball park as gasoiline
Known chemistry - no exotics required
No carbon - gets completely away from CO2.
OK there is downside in the toxicity, but one report I read said that ammonia was routinely sprayed directly onto arable land - so that can't be insurmountable.

Why is it not being more intensively pursued ? Great question. Maybe because it is not sexy - not a lot of research dollars in it. And it cuts across powerful vested interests. Imagine if someone came up with a haber-process in a refrigerator sized box. With a small windmill, everyone could make their own power and transport fuel from no more than water and air...

Devil - for once I find myself disagreeing with your naysaying - this is a most fascinating area - Energy Spin - please keep us posted !

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Unread postby Devil » Mon 08 Aug 2005, 06:07:41

Oily_Bill wrote:Devil - for once I find myself disagreeing with your naysaying


The implication here is I'm a naysayer. If I have earned this reputation - which is unjustified as I'm an ayesayer when it comes to pragmatic energy production with minimal environmental impact - it may be because I try to keep my feet on the ground, rather than my head in the rarified regions of the ozone layer.

What exactly do you disagree with? I make several points why I believe that the disadvantages of NH3, taken together as a whole, by far outweigh its advantages. If I had more time, I could enumerate several fallacies and non sequiturs exposed on this thread. If you have specific proof of any error in my statements, please let this thread know. And I don't want "this seems" - I want facts.
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Unread postby Oily_Bill » Mon 08 Aug 2005, 07:06:09

Hello Devil,

a detailed response to your requests for input on your previous comments has been made by EnergySpin, above. No need to repeat.

A powerful arguement that the potential health effects are managable is that the US alone already produces and transports over 30 Million tonnes of anhydrous ammonia per annum. Much of this is sprayed directly onto farmland by people towing tanks behind tractors.

Ammonia could only ever be an energy store. However, its physical characteritics and energy content compared to gasoline, make it a possibility in this role which must be researched. Vehicle storage tank size would be comperable to running on Propane.

The future may be a relatively powered-down and died-off scenario, where sufficient electrical energy is available from wind, tidal, hydro and possibly nuclear sources. The shortage would be of portable energy. Whether there remains any heavy industry at that point is of course a highly debatable point. Ammonia may only be part of the the future if heavy chemical industry still exists - unless some miniaturisation and localisation of the Haber process could be engineered.


I appreciate that you are well researched - your responses on other threads are always sharp and to the point, and expose any underlying factual falacies which may be present. Therefore, when I saw your name posting in this one I envisioned the demolision of 'ammonia as fuel' as yet another hair-brained idea. But the punchline never came. :)

Look forward to your help in exploring this further.


Best regards
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Unread postby Starvid » Mon 08 Aug 2005, 07:29:57

Alternative fuels are not my area of expertise at all, but I just want to butt in that the Vectrix people are building an hybrid electric-methanol fuel cell scooter, which will be ready in 2007 I believe. So at least some people want to try this out in the real world.

OT: Devil, what is your favorite alternative energy carrier, for cars? Even if the amount of cars might have to be reduced, a lot of people will still need them. What energy carrier do you speculate they will mainly use?
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Unread postby EnergySpin » Mon 08 Aug 2005, 08:27:58

Oily_Bill wrote: Imagine if someone came up with a haber-process in a refrigerator sized box. With a small windmill, everyone could make their own power and transport fuel from no more than water and air...

Oily_Bill

Check a few examples of a "Haber in a box". It is not exactly Haber (since it happens in atmospheric temperature.
http://pubs.rsc.org/ej/CC/2000/b004885m.pdf
Click

In any case .. I am not an expert on chemistry. Trying to tie different bits and pieces together. For the next 20 days my time is limited (have to get ready non only to change continents but to find an apartment when I return to the States next year), but I would appreciate any comments and data on the "weak" aspects (and I'm sure there are still many) of this. At the very least, I got enough data to refure the point that fertilizers will be gone overnight post peak oil/gas :roll:
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Unread postby EnergySpin » Mon 08 Aug 2005, 09:11:17

Oily_Bill wrote:
The future may be a relatively powered-down and died-off scenario, where sufficient electrical energy is available from wind, tidal, hydro and possibly nuclear sources. The shortage would be of portable energy. Whether there remains any heavy industry at that point is of course a highly debatable point.

Oilly_Bill you cannot have nuclear or wind turbines or solar or tidal without "heavy industry". It is quite likely that future's industry will be heavy (in the sense that high tech [processes are involved) but reduced in volume.
Heavy/high-tech is not always equat to "bad". For starter's if all heavy industry is gone, then who will replace the wind/solar/nuclear when they fail?
Sustainability should take into account the sustainability of the industrial process in the future. People (both sides) equate sustainability with a anything that existed before the industrial revolution. This is unfair and short-sighted. Modern industrial processes are extremely efficient in their use of energy. They are not efficient in the management of material throughput ... this is something that is solvable (research field is known as industrial ecology). The way I see it , the biggest challenge of PO is to align the level of technology needed to solve a problem with the intrinsic difficulty of the problem at hand. There might be low tech solutions to big problems (i.e. change in agricultural practises is one, since it is relevant to the use of fertilizers, environmental impact, and even carbon sequestration) and high-tech solutions to big problems (solar and modern wind is extremely high tech btw and much more "sustainable" than low tech turbines/solar panels from 30 years ago). I can cite a great number of examples from my field (medicine) where "low-tech" solutions are more appropriate to particular problems. In my view this has to do with something I (maybe others as well, I might have picked up the term from somewhere) call "embodied knowledge". Since solutions to problems always incorporate knowledge about the domain of the problem , there is a distinct (actually pretty significant chance) that a high "embodied knowledge" level translates to a decreased complexity level (and hence level of technology needed for the implementation) than a naive solution. This is especially true when biological/medical problems are concerned. Due to the degree of complexity of the systems and the fact that failures only happen at certain points ("hubs" in network theory) a solution that addresses a small number of root causes is more likely to succeed and be conomical /practical than a solution based on a less complete understaning of the problem. Example: lung cancer. Curing lung cancer after it has occured is very difficult and only happens after extensive surgery chemoradiation regimens. Knowing tha smoking causes lung cancer allows someone to promote smoking cessation measures (low tech solution).
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Unread postby Devil » Tue 09 Aug 2005, 05:20:30

Starvid:
I have no miracle solution for cars. IMHO, with our current state of technology and infrastructure, there is no alternative. I cannot believe that electric cars, hydrogen or ammonia (either in FC ir ICE variants), LPG, NG are acceptable. In the short term (<20 years), the only viable solution is to reduce consumption of petroleum fuels, thinned out, where practicable, with biofuels.

Call me an iconoclast, but if each family unit were rationed to, say, 25 l of fuel per month, this would go a long way to solving the problem. Mom could take the kids to school 2 km away in a Hummer twice per month or she could have a 4 l/100 km car, such as a Prius, and do the round trip 150 times, while Pop had to walk or cycle to work. Alternatively, and better still, the kids could walk off their obesity by going to school on foot, while Pop used a moped to go to work, Mom organised a single trip/month to the mall in her Prius and used the local convenience store on foot for daily needs like milk, eggs and bread. However, this does require forethought, which is sadly lacking in a large section of the populace. But this plan would allow some recreational use of the ration.

Unfortunately, I don't have access to a Prius or other hybrid and have a heavy 2 l car (8 years old), so my consumption is high (~9 - 11 l/100 km). By organising our life, our total consumption now is ~40 l/month. If I could get a low-consumption car (none are imported here), I could reduce this to well under 18 l/month with no change in our lifestyle. A 25 l ration would therefore be perfectly feasible and would reduce overall fuel consumption in half (more in the USA, where your SUVs reign supreme).

This rationing would a) help spin out remaining stocks, b) reduce pollution and negative health effects, c) ensure a healthier lifestyle, d) reduce climate change effects, e) force gas-guzzlers off the road, f) make people think, g) reduce road accidents, h) improve the US and Oz public image. OK, there may have to be special dispensations, e.g., for handicapped persons, for regulated company car use (no use of company-owned vehicles for any private use, not even commuting) etc.
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