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#26 2019-04-14 12:05:41

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,362

Re: Fuel Cell Development, Application, Prospects

SpaceNut,

Fuel cell consumable / wear components include intake air filters, air intake pump motors, solenoid-operated valves, and membrane electrode assemblies, which includes air tight gaskets / gas diffusion layers / catalyst membranes.  The catalysts are recyclable, the gaskets are recyclable, and the membranes themselves are recyclable plastics, such as PTFE or PET.  Recall that Paragon SDC's Ionomer Water Processor (IWP) also uses Nafion for water filtration.

Some of these materials have service lives of 100,000hrs or more.  Incidentally, the RB211 turbofans, renown for their time-on-wing, have 20,000hr TBO's.  Some have gone as much as 40,000hrs on-wing.  If the air pumps use magnetic bearings, then their service lives are only limited by material service lives, which also greatly favors CNT composites over metals.  The Toyota and Honda fuel cells have survived for 15,000hrs or more.  California has some fuel cell powered buses that have gone 25,000hrs.  Ballard, a Canadian / global company, did the fuel cells for those buses.  The key point is that those fuel cells were still within rated power output at the end of their service lives.  The stationary electric generator fuel cells should easily achieve 100,000hrs or more since some have already done that.

The Hydrogenics H2 generator-in-a-box reverse fuel cells have TBO's in excess of 50,000hrs.  In the past, I've mentioned Proton OnSite's reverse fuel cells for use on Mars for ISPP.  Both are CONEX box solutions.  Hydrogenics uses cheap KOH catalysts.  Minor creativity on the part of the manufacturer would yield a product with a rough size and shape of a small jet engine.  Most of their boxes are just empty space for ease of maintenance.  There's no reason I can think of as to why N2 couldn't be introduced downstream of the water splitting to produce NH3.

Hydrogenics - HyStat Hydrogen Generators

Ever seen a reverse fuel cell the size of a pair of mini fridges that can produce 1,350kg of H2 per day?:

Hydrogenics - Hylyzer 600 - 3MW Hydrogen Electrolyzer

Well, there it was.  That's enough to fill the 537,000 gallon LH2 tank used by SLS in just over 106 days.

This provides more detail on the economics of H2 systems:

Hydrogenics - Cost Reduction Potential for Electrolyzer Technology

The Toyota Mirai uses a 2kW/kg fuel cell that weighs approximately 57kg.  It weighs more because it's less integrated than the Intelligent Energy fuel cell.  The 5kg of compressed H2 required to drive 312 miles is stored at 700 bars in a pair of tanks that weigh 83kg.  The Tesla Model S battery pack weighs 540kg to go 265 miles.  An equivalent LNH3 fuel tank would store 11 gallons of LNH3 at no more than 17 bars (~250psi) and might weigh 48kg (11.4 gallon steel propane tank) with fuel.  An Intelligent Energy fuel cell that provides equivalent power would weigh 38kg.  That means that a LNH3 powered Mirai's entire power plant, with fuel, would weigh slightly less than the Mirai's fuel tanks and 5kg of H2.  The energy density of the Tesla's battery pack needs to improve to just over 1kW/kg to compete with the fuel cell on weight.

It doesn't take much math to figure out why fuel cells outperform batteries as continuous power requirements increase.  To add another 265 miles of range, the Tesla needs to add another 86kg of battery at 1kWh/kg.  Alternatively, the battery's energy density has to more than double.  The fuel cell only requires another 48kg of fuel tank and fuel (62.59lbs of LNH3 and 40 pounds of steel).  However, CNT composites are a minor fraction of the weight of steel and much stronger.  A CNT composite tank with equivalent strength that utilizes existing CNT fabrics in the wrap (at less than 1/6 the strength of recent improvements reaching 90% of theoretical strength) would weigh about 2 pounds.  At near theoretical strength, we're talking about mere ounces.  We can afford extreme durability with CNT at those strength levels, so perhaps 1 pound of tank per 10 gallons of fuel to repel handgun bullets and handle most crashes.

The Intelligent Energy fuel cell design uses byproduct water as an evaporative coolant.  That's it's only real claim to fame, but it simplifies the complete fuel cell design and makes it lighter.  If the stack plates and end plates were made from CNT instead of Aluminum, it'd be a fraction of the weight of their current design.  Volumetric power density wouldn't improve, but gravimetric power density would at least triple.  If that happens, then combining that with existing copper and iron electric motors produces a power delivery system on par with the very best jet engines once fuel weight is taken into account.  If CNT wiring is used in the motors, then we'll easily exceed the power-to-weight ratio of any jet engines.  At 10kW/kg (fuel cells) and 25kW/kg (motors), a 10MW system would weigh 1,400kg, whereas a 10kW/kg jet engine would weigh 1,000kg.  After the gas turbine powered jet taxis to the end of the runway and takes off, that 400kg weight advantage goes up in smoke with the gas burned to leave the ground.  The economics of operating the kerosene burner only gets worse from there.  Bean counters can figure this stuff out with pocket calculators.  No advanced degrees or advanced mathematics are required.

One quick final note about why we need high strength composites...  Making 1kg of steel equates to 2kg - 2.5kg of CO2 and 1kg of Aluminum equates to 11.2kg - 12.6kg of CO2.  Aluminum alloys are typically more expensive than common types of steels because making Aluminum is a very energy-intensive process.  The current methods for making Lithium-ion batteries are far worse, emitting 150kg - 200kg per kWh of storage capacity.  Capturing CO2 to make carbon fiber or CNT consumes CO2, rather than emitting it.  We need to produce less metal and consume more Carbon.

The Life Cycle Energy Consumption and Greenhouse Gas Emissions from Lithium-Ion Batteries

Batteries can be part of the fight against climate change - if we do these five things

Unsurprisingly, we're not doing any of those five things at any significant scale.  Assuming we only emit 100kg of CO2 per 100kWh battery produced, the goal of putting 100 million battery powered cars on the road by 2030 will emit a further 10 gigatons of CO2.  In 2010, we emitted 9 gigatons into the atmosphere and in 2018 it was 37.1 gigatons, so we're talking about a substantial percentage of the yearly emissions total.  Adding battery-based grid storage to a dramatic increase in the EV fleet seems like a step in the wrong direction.  I suppose we could make every car battery-powered and every grid storage solution battery-powered if we want to accelerate the warming process, but I'm not in favor of exacerbating the problem.  In short, making more metals is not the answer to reducing emissions.

New Global CO2 Emissions Numbers Are In. They’re Not Good.

We need raw materials that consume CO2 to produce useful products.  CF and CNT are very useful products.  Most structures that don't have to withstand intense heat are dramatically improved by those products in all ways that make any material useful, namely strength-to-weight ratio, stiffness, and durability.  Any process that emits CO2 that we must capture should ideally also produce an energy dense / Hydrogen-rich non-Carbon-based fuel, such as NH3.  Apart from batteries, which are still needed in mass quantities for other purposes, we have plenty of metals in reserves to make things that we must make from metals.

We're not improving our situation with what we're currently doing.  It's time to admit there's a problem and try something new.

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#27 2019-04-14 18:19:49

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,362

Re: Fuel Cell Development, Application, Prospects

tahanson43206,

Everyone has pre-conceived notions of what they want their future to become, to include myself.  I'm a big proponent of nuclear power, for example.  However, I can also accept that there is widespread fear of nuclear radiation amongst the general populace, there is some merit to those fears given past nuclear accidents and nuclear weapons development and use, and that those people don't want more nuclear power.  If I could wave my magic wand, I would move all the nuclear weapons off this planet.  Their only acceptable subsequent uses would be protection of our home from incoming asteroids of destruction of hostile extraterrestrial invaders.  I seem to have lost my magic wand, so I can't do that.  That still leaves the threat of nuclear accidents.  I think the fear of radiological contamination is somewhat irrational, given the sum total of all known health effects or lack thereof, but it's quite real to them.  Therefore, I must consider alternatives that also produce acceptable results using available and emerging technologies.  It's not written in stone anywhere that non-nuclear alternatives can't work just as well, though it considerably complicates the production problem at the incredible scale at which we're presently consuming energy.  My solution to that problem is to make everything a lot lighter by using advanced composites that are already finding their way into ordinary consumer products because their mechanical and electrical properties are so desirable.

I approached this problem from a pragmatic standpoint.  I know what we already have that works well at significant scale.  I know that irrespective of what I would find most desirable in energy substitutions, I likely won't get much of what I want.  I'm also convinced that technology inevitably marches forward.  If something isn't working well enough, then eventually we stop using it.  Despite how good they were when we perfected the technologies involved, that still applies to combustion engines and hydrocarbon fuels.  Roughly doubling the efficiency of gas powered machines that do mechanical work, such as cars / trucks / aircraft / ships and halving the weight of their structures is enough to reduce our energy consumption to the point where non-nuclear alternatives are both feasible and desirable, since like-kind functionality is provided.

Known chemistry provides a very limited number of acceptable alternatives to hydrocarbon fuels.  Existing batteries are so far below the amount of energy stored in chemical bonds that the number of practical applications that batteries can be used for has been stunted.  They work well for portable electronics or power tools and work passably well in light vehicles.  Anything much beyond that is a losing proposition when simple physics and math are taken into account, presuming the desire is to create a machine with like-kind functionality.

Will we see LNH3 powered vehicles as the first application?

Of course not.  There will be lots of regulatory and personal prejudice inertia to overcome before that happens.  Battery powered vehicles had to overcome the same stigmas and the market for those is relatively small.  At present, there are no realistic alternatives for ships and aircraft.  That's why all of them are powered by liquid hydrocarbon fuels.  If we want to get rid of those emissions, then we must pursue alternatives that account for what existing technology can realistically achieve without protracted development.

In closing, I'll state what else I know.

I know that nuclear fission is wildly unpopular or extremely controversial at best.  I can't convince anyone of what simple math hasn't already convinced them of, so I've stopped trying.  If they haven't already figured out that France is one of the very few industrialized nations with a significant population in Europe, and that the French predominately use nuclear power to prevent CO2 emissions, then I guess they're not going to figure it out because they're after a specific result that overrides their concerns about CO2 emissions.  They aren't interested, plain and simple.  Preaching to the choir is equally pointless.

I know that solar and wind have intermittency problems that are quite real and that the problems have never been adequately addressed.  I have to believe that if it was as simple or as easy to do as some claim, then it would've been done already.  We've thrown truck loads of perfectly good money at better batteries, only to discover that making or breaking chemical bonds yields substantially greater quantities of energy than electrochemical reactions.  For some weird reason, scientists already knew that more than a century ago.

I know that our consumption of hydrocarbon fuels continues to increase because no realistic alternatives have been pursued with the same vigor as solar panels and batteries.  We keep ignoring what we've known all along, in blind hope that some miracle technology will fall from the sky.  Maybe it'll show up on our doorstep tomorrow, but real engineering doesn't use technology that we might have at some point in the future.  It requires known quantities to work with in order to create useful things.

If the past is any indicator, no new miracle technologies are on their way.  I would be ecstatic if there were, but I haven't found any unless claims without evidence count.  What we have witnessed is slow but steady refinements of existing technologies.  We've experimented with technologies that are presently beyond our capabilities, such as fusion and anti-matter reactions, but we've yet to obtain more energy output than input and we simply don't have the requisite technology and know-how to do that.

I know that computer technology and materials science and fabrication methods have improved by leaps and bounds over the past decade.  As a result, I have far more faith (evidence, really, since we've actually done these things at global scale) in our ability to refine existing lightweight composites (we're now producing tens of tons of CNT's per year), fabricate fuel cells (we've used these at limited scale for at least a decade now and there's no mysteries left about how they work and how they fail), and produce cleaner fuels (we've been producing LNH3 for a long, long time now) than I do in our ability to create revolutionary new energy technologies (this has happened but a few times in all of human history).

It's fun to daydream about what will be possible in the future, but somehow we have to make our way to that future.  I, for one, would like concrete results within my lifetime.  I believe we can obtain a step change in energy use efficiency over combustion through synergistic use of advanced composites, fuel cells, electric motors, and even solar panels and wind turbines.  If there's a more practical way to achieve that outcome, then I'm open to any other ideas that our other members have.

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#28 2019-04-14 19:03:41

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

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#29 2019-04-15 05:52:15

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,752

Re: Fuel Cell Development, Application, Prospects

For kbd512 .... Thank you for #27.  I like the mix of philosophy and technology, and I ** really ** like the fact it is now part of this topic, which anyone who chances upon this site can read.

For SpaceNut ... thank you for your searches in support of this topic.

The challenge I am facing it to try to keep up with the flow, and we've only seen contributions by a few forum members so far. 

That's on top of the time it will take for deep dives I'd like to do, such as the one on how pure carbon can be produced as a byproduct of the manufacture of a chemical.

(th)

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#30 2019-04-16 08:46:31

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,752

Re: Fuel Cell Development, Application, Prospects

For SpaceNut (and for the record) ...

SearchTerm:WaterPriceOf

The price of electrical power in New Hampshire, as reported by SpaceNut, inspired me to record here the price of water at a location in central US...

... tap water -- meeting or exceeding all state and federal drinking water standards -- remains a great value at less than an penny a gallon.

For comparison for future readers, the federal minimum wage today is: $7.25.  A person making that wage in an hour can buy 725 gallons of drinking water.

The price of drinking water on Mars, including all needed minerals for human health, and excluding all pathogens and non-helpful compounds, will be greater.

However, a minimum wage on Mars will likely be greater as well.

(th)

SpaceNut wrote:

Kbd512 thanks for post #13 as its discription is quite the same for all versus of electrolysis units or for a fuel cell from all of the stuff we have talked about including Moxie.
...
I reported from the documents the cost for non free energy creation of NH3 and its plausible level of power from it in post  #13 which was

World production 150MM tons -current cost about $0.5/L; Energy density 4.3 kWh/L

currently PSNH is charging 9 cents a kwhr for power so cost wise to what it can deliver is 78% efficient for what it cost to create so free energy is the only way to go but even that does cost to set up to capture for NH3 creation. This is true for any hydrogen based economy....

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#31 2019-04-16 18:39:34

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,752

Re: Fuel Cell Development, Application, Prospects

For kbd512 ....

Following up on CO2 and Haber-Bosch ...

kbd512 wrote:

...
The Haber-Bosch process is not CO2-free, but this should be seen as an added bonus product if we commit to using the CO2 like so:
...

I found multiple sources covering Haber-Bosch, including one to which Jim Clark contributed.

I'd like to offer this one as preface for a question:  https://simple.m.wikipedia.org/wiki/Haber_process

The gases for the Haber process must be prepared before changing them into ammonia. After that is done, ammonia is created by using magnetite (iron oxide) as the catalyst:

N2 + 3H2 is in equilibrium with 2NH3
In this process, only about 15% of the nitrogen and hydrogen is changed into ammonia. However, the unused nitrogen and hydrogen is recycled. Overall, 98% of nitrogen and hydrogen can be changed into ammonia.

References   
Edit
Jim Clark (2002), The Haber Process for the manufacture of ammonia, retrieved March 14, 2010

so my question is: Would I be correct in assuming that the CO2 you've described is produced while the production equipment is brought to a pressure of about 200 atmospheres?

The Haber process or the Haber-Bosch process is a chemical reaction that uses nitrogen gas and hydrogen gas to create the chemical compound ammonia. The Haber process uses temperatures ranging from 400°C to 450°C under a pressure of 200 atm.[1] The Haber process uses a catalyst mostly made up of iron.

I assume the heating could be performed using renewable resources?

I also assume heating with hydrocarbon fuels is by far and away the most cost effective solution.

(th)

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#32 2019-04-16 18:54:42

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,752

Re: Fuel Cell Development, Application, Prospects

For SpaceNut ...

Just FYI ...

I wrote to Dr. Douglas Macfarlane to inquire if one of his students might be interested in helping with this topic.

Douglas Macfarlane
Professor

Professor, Sch of Chemistry

Email
Douglas.MacFarlane@monash.edu

Dr. Macfarlane's work is described in the article at this link:
https://www.sciencemag.org/news/2018/07 … out-carbon
(th)

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#33 2019-04-16 20:49:47

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Fuel Cell Development, Application, Prospects

Sounds like a plan that much like a few real scientist use to do here but confindentiality has been a limiting factor for what they can say.

Not surprising that Austrailia has such solar potential but the area of new mexico has such potential for the US as well.

devices, about the size of a hockey puck and clad in stainless steel. Two plastic tubes on its backside feed it nitrogen gas and water, and a power cord supplies electricity. Through a third tube on its front, it silently exhales gaseous ammonia, all without the heat, pressure,

This is good as the Haber process requires great pressure to make work.

Step 1 is solar array into a bank of electrolyzers, which split water into H2 and O2. in a tank which has proton-permeable membrane where the electrodes for freeing up the hydrogen is on one side and the atractor for the hydrogen is on the other which has the source of nitrogen gas coming in. The oxygen is vented to allow the hydrogen to cross the membrane without rebonding as it passes to the nitrogen side of the tank. This is where the nitrogen attaches to it and makes the ammonia.

Step 2 is the fuel cell which reactions generally have efficiencies of between 1% and 15%, and the throughput is a trickle.

2-meter-tall reactor that is dwarfed by a nearby coal reactor. When switched on, the reactor will "crack" ammonia into its two constituents: H2, to be gathered up for sale, and N2, to waft back into the air.  the reactor will produce 15 kilograms per day of 99.9999% pure hydrogen, enough to power a few fuel cell cars.

Development of Catalytic Reactors and Solid Oxide Fuel Cells Systems for Utilization of Ammonia

The reaction temperature of ammonia cracking to nitrogen and hydrogen, being about 600°C or higher, is close to the operating temperature of solid oxide fuel cells (SOFCs). In this study, 200 W class and 1 kW class SOFC stacks were applied for ammonia fueled generation systems.

Temperatures are to hot....

This article indicates
Low Temperature Ammonia Cracking Membrane Reactor for Hydrogen Generation

Hydrogen breakthrough could be a game-changer for the future of car fuels

Ammonia can be stored on-board in vehicles at low pressures in conformable plastic tanks. When the components of ammonia are separated (a technique known as cracking) they form one part nitrogen and three parts hydrogen. Many catalysts can effectively crack ammonia to release the hydrogen, but the best ones are very expensive precious metals. This new method is different and involves two simultaneous chemical processes rather than using a catalyst, and can achieve the same result at a fraction of the cost. Our approach is as effective as the best current catalysts but the active material, sodium amide, costs pennies to produce. While our process is not yet optimised, we estimate that an ammonia decomposition reactor no bigger than a 2-litre bottle will provide enough hydrogen to run a mid-range family car.

So power is put into the cracking device to free up hydrogen to be combusted in an ICE.

This put the water electrolysis machines which can be done with the same engine at about the same which is called brown gas injection as its a hydrogen and oxygen sent into the intake with gasoline to make it work once the engine is running the gas is leaned away so long as the source of hydrogen is sufficient to keep the engine running.

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#34 2019-04-17 07:08:45

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,752

Re: Fuel Cell Development, Application, Prospects

For SpaceNut #33 ....

Thank you for your appreciation of Dr. MacFarlane's work, and for your deep dive into the background and potential development opportunities.

I am hoping one of the students will decide to help us (forum members directly, and Internet readers indirectly) to understand the work already completed, and (in particular) how we can work in our respective nations to accelerate the pace of growth of an all-NH3 energy infrastructure.

The estimate of 12 years until hydrocarbon Armageddon may be high or low, but it is a useful target date for starting to (quoting Adam Smith) "put people into motion".

What I am sure CAN happen, is that corporations (or groups of comparable capability) can carry out all the steps needed to implement an NH3 economy, from production of the product itself, marketing, distribution, delivery in homes and businesses, and recovery of water for consumption or industrial processes including agriculture.

(th)

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#35 2019-04-17 18:52:28

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Fuel Cell Development, Application, Prospects

The other liquid fuel for delivery of hydrogen for use by a vehicle.

https://en.wikipedia.org/wiki/Water-fuelled_car

https://www.scientificamerican.com/arti … -for-fuel/

experts say the energy equation on this type of system is not, in reality, efficient at all. For one, the electrolysis process uses energy, such as electricity in the home or the on-board car battery, to operate.

its not about the energy or the efficiency of the process its about water being free and the car moving...

The Truth About Water-Powered Cars: Mechanic's Diary

Yes, you can run your car on water. All it takes is to build a "water-burning hybrid" is the installation of a simple, often home-made electrolysis cell under the hood of your vehicle. The key is to take electricity from the car's electrical system to electrolyze water into a gaseous mixture of hydrogen and oxygen, often referred to as Brown's Gas or HHO or oxyhydrogen. Typically, the mixture is in a ratio of 2:1 hydrogen atoms to oxygen atoms. This is then immediately piped into the intake manifold to replace some of the expensive gasoline you've been paying through the nose for these last couple of months. These simple "kits" will increase your fuel economy and decrease your bills and dependence on foreign petroleum by anywhere from 15 to 300 percent.

Electrolysis of ammonia NH3 would give slightly better performance.

https://engineering.mit.edu/engage/ask- … -gasoline/

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#36 2019-04-17 21:40:32

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Fuel Cell Development, Application, Prospects

https://afdc.energy.gov/fuels/hydrogen.html
fuel cell vehicle information

https://gas2.org/2013/07/09/5-reasons-t … o-propane/
The carbon is why its not any better but we can get flow rates for numerical numbers for hydrogen burning

http://coenergy.net/benefits-propane-converting-car/

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#37 2019-04-18 09:38:17

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,752

Re: Fuel Cell Development, Application, Prospects

Adding to theme of recycling found in this topic:

https://www.yahoo.com/finance/news/appl … nance.html

The article above describes an initiative by Apple to try to recycle as much material as possible from obsolete electronic devices.  Apparently what is learned is to be made available to all who may wish to pursue the idea.

It seems to me that development of this capability would be particularly helpful on Mars, where waste would be more costly that is the case on Earth.

(th)

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#38 2019-04-18 20:13:56

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Fuel Cell Development, Application, Prospects

I remember why I was looking at the water electrolysis Brown gas vehicle injection use as it was during the years when gas was almost $4 a gallon and propane had sky rocketed as well upward.

https://www.rmcybernetics.com/science/d … -fuel-cell

How to Turn Water into Fuel by Building This DIY Oxyhydrogen Generator

How to Convert Water Into Fuel by Building a DIY Oxyhydrogen Generator

https://www.popularmechanics.com/cars/h … tural-gas/
Home natural gas is delivered at about 0.5 psi, but natural gas in vehicles needs to be pressurized to 3600 psi.

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#39 2019-04-19 03:12:15

elderflower
Member
Registered: 2016-06-19
Posts: 1,262

Re: Fuel Cell Development, Application, Prospects

Don't do this. A mixture of oxygen and hydrogen is extremely easy to ignite and delivers a lot of energy very quickly (an explosion).
The electrolyser will consume a bit more energy than it stores in the product gases as it cannot be 100% efficient, so you must provide extra electricity to make it work. When the products are burned in a heat engine there will be a massive loss of energy as you can't exceed the efficiency of the Carnot cycle engine. A Carnot engine depends only on the temperatures at which heat is supplied and at which waste heat is removed. If you feed it to a fuel cell there are still constraints although not so severe as those of a heat engine.

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#40 2019-04-19 19:15:15

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Fuel Cell Development, Application, Prospects

Yes an uncontrolled brown gas vapor would be explosive but so many have been doing just that for quite some time.

Build it right and you have no problems.

None of the consumed energy from the running engine matters, when you are looking at water which is free versus the rising cost of gasoline. Since only about 20% gets to the wheels, means there is lots of energy to capture for the electrolysis process or supplement what you can with a bit of solar panels on the roof, permanent magnets for generators rather than alternators.

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#41 2019-04-20 12:58:43

kbd512
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Posts: 7,362

Re: Fuel Cell Development, Application, Prospects

What is so fundamentally "different" about the approach I suggested?

1. We're using a single process to give us most of what we need to build and to power.  We're using all of the byproducts from the Haber-Bosch process.  It makes no sense to only obtain useful benefit from the Ammonia when the Carbon and Oxygen products are just as valuable.

Mining and refining metals requires copious quantities of energy.  When there was no other suitable replacement material available, it made sense to do it.  That is no longer the case.

Mining and refining Carbon for composites requires copious quantities of energy.  The same aforementioned principle applies here.

Dumping our absolute "best" (in every conceivable sense of the word) structural material into the air won't solve the emissions problem.  Coming up with other schemes, such as power-to-gas, whereby we expend even more energy to make liquid hydrocarbon fuels from scratch and then dump the CO2 back into the atmosphere is an even less efficient way to put ourselves in the same predicament.

2. Using fuel cells is at least doubling, if not tripling in most use cases, our energy usage efficiency and still using existing fossil fuel resources to do it.  I fully expect that in the near future we'll have a reasonably efficient method to make liquid fuels from scratch, but that's not quite ready for prime time.

We don't "make" separate Carbon for the industries that require lightweight composite materials.

We don't "make" separate Oxygen for the chemical industries and space launch services industry.

We don't "need to make" metals for structural applications.  Those materials do not give us superior mechanical properties in most uses cases, high temperature applications notwithstanding.

3.   The complete process generates very little waste, whether we're talking about inefficient fuel consumption or waste in the form of what would otherwise be valuable byproducts.

We're eliminating supply chain and energy usage inefficiencies through a form of "vertical integration" wherein the useful products created by different industries are obtained from a single chemical (present) or electrochemical (future) process.

Finally, and perhaps most importantly, we're not dumping more CO2 into the atmosphere.  We're arresting our emissions problem, rather than continuing to compound our emissions problem using new technology.  When you find yourself in a hole that you can't get out of, the first step is recognizing the problem.  The second step is to stop digging.  The third step is to figure out how to use your tools to get out of the hole.

I'm interested in the 3rd step of solving that problem.  How do we use what we have to get out of the hole?  If we're not making upward progress, then what are we really doing?  I'd say we're making the problem worse.  Naturally, other opinions will vary.

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#42 2019-04-20 15:08:56

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Fuel Cell Development, Application, Prospects

It has been said that Ammonia Fuel Cell is Cost Competitive with Diesel Generators

Unlike diesel generators that require time-consuming and expensive monthly fueling and maintenance at each tower, a single 12-ton tank of ammonia provides the GenCell A5 with enough fuel for a year of 24/7 operation.

at 1kWh.

https://www.ammoniaenergy.org/tag/nh3-fuel-cell/

https://arpa-e.energy.gov/?q=slick-shee … ing-soon-0

More Progress for Automotive-Oriented Direct Ammonia Fuel Cells

power density of 450 mW/cm2 has been demonstrated for a direct ammonia fuel cell [DAFC] using an alkaline membrane electrolyte

http://jes.ecsdl.org/content/165/15/J3405.full

In order for fuel cell electric vehicles to be competitive, the total untaxed, delivered and dispensed, cost of hydrogen needs to be less than $4/gge. A gge, or gasoline gallon equivalent, is the amount of fuel that has the same amount of energy as a gallon of gasoline. One kilogram of hydrogen is equivalent to one gallon of gasoline.

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#43 2019-04-20 17:41:34

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Fuel Cell Development, Application, Prospects

Ammonia-for-Power-Table-6.png?w=656&ssl=1

https://www.ammoniaenergy.org/gencell-l … onia-fuel/

The system, which fits into a 20-foot shipping container, includes four primary pieces of machinery. First is GenCell’s patented ammonia cracker, which decomposes ammonia at <700 °C into a mixture of hydrogen and nitrogen.

ZBT-ammonia-fuel-system-Sankey.png

Second is an alkaline fuel cell generator, which uses an electrolyte of potassium hydrochloride (KOH) to generate 4 kW power from the hydrogen fuel.

Fuel-Cell-Schematic.png?resize=234%2C300&ssl=1

Third and fourth are the "energy bridge for regulating power output" and "heat utilization unit for dissipating excess heat." More details about the A5 Off-Grid Power Solution are available via GenCell’s website, which claims that the system offers “Green Energy at Half the Price of Diesel …

A single 12-ton tank of ammonia provides enough fuel for a year of 24/7 operation. Ammonia containing 17.5 wt% hydrogen.

https://www.gencellenergy.com/our-products/gencell-a5/
When installing the GenCell A5 at 1,000 sites or more, you can save up to $250 million or more compared to diesel solutions.”

According to ZBT’s presentation, its 4 kW ammonia-fueled alkaline fuel cell achieved an efficiency of 59.52%.

According to GenCell’s website, its 4 kW ammonia-fueled alkaline fuel cell achieves an efficiency of 52% (fuel cell generator only), consuming a maximum of 2.5 kg/hour ammonia. If combined heat and power (CHP) is considered, the system’s efficiency increases to 87%.

Alkaline fuel cells (AFCs) were the first to be developed with ammonia as the fuel, beginning in the 1960s. Low-temperature (50 to 200°C) AFCs traditionally use a potassium hydroxide (KOH) electrolyte; a molten hydroxide (NaOH/KOH) electrolyte operates at higher temperatures (200 to 450°C).

Dincer-energy-exergy.jpg?resize=768%2C585&ssl=1

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#44 2019-04-20 18:49:47

tahanson43206
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Registered: 2018-04-27
Posts: 16,752

Re: Fuel Cell Development, Application, Prospects

More on Australian Ammonia/Fuel cell initiative, from July 2018:

https://www.sciencemag.org/news/2018/07 … out-carbon

This article by Robert F. Service reports on current status and goals for various points along the supply > customer use chain.

(th)

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#45 2019-04-20 20:21:41

SpaceNut
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Re: Fuel Cell Development, Application, Prospects

Depending on the kilowatt that we need for the electrical system here is a company which has several different sized units.
https://www.fuelcellstore.com/fuel-cell … ell-stacks

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#46 2019-04-21 19:56:32

SpaceNut
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Re: Fuel Cell Development, Application, Prospects

Important post from

kbd512 wrote:

A fuel cell will still work at high altitude, but it'll produce proportionally less power with proportionally less atmospheric O2 content to react with the H2.  The same is true of all existing combustion engines except rocket engines, to include jet engines.  The goal here was to illustrate the feasibility of creating a CO2-free alternative propulsion system that provides a like-kind replacement for existing turbofan engines. 

I've done my best to show that that's already feasible using current automotive LNH3 plasma cracker technology (Toyota), current automotive PEM fuel cell technology (Intelligent Energy), and axial flux electric motors (Magnax).

For what should be obvious reasons, I do not want the fuel cell to be able to produce more power than an existing turbofan engine that it's intended to replace.  If the fuel cell powered plane makes sea level power at high altitude, then it can overspeed the fan and/or exceed the Vne of a subsonic airliner's airframe in level flight.  Any design that intentionally permits that to occur is a bad design

This goes with my posted information in #43 as it creates a carbon free fuel to use as kbd512 has pointed out.

There still is a need for a battery to not only start the process of hydrogen releasal but also to aid in power conditioning for surge levels.

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#47 2019-04-21 21:30:46

SpaceNut
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Registered: 2004-07-22
Posts: 28,747

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#48 2019-04-22 06:26:41

tahanson43206
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Registered: 2018-04-27
Posts: 16,752

Re: Fuel Cell Development, Application, Prospects

For SpaceNut re #47 ....

Thanks for another collection of interesting and helpful references ...

You may well have designed it this way, but the image links to this:
https://www.ammoniaenergy.org/ammonia-f … niversity/

And THAT pdf describes the 1 kw stack in some detail.   

This is encouraging news, for sure!  In my first scan of the pdf, I could not tell if the ammonia fed into the system is anhydrous or cut with water, and if so, by how much.  kbd512's posts have included mention of the advantage of shipping ammonia in the aqueous form for safety reasons, but I'm wondering if the ammonia has to be separated from the water before it is fed into the cracker.

(th)

Last edited by tahanson43206 (2019-04-22 13:04:15)

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#49 2019-04-27 20:08:24

SpaceNut
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From: New Hampshire
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Re: Fuel Cell Development, Application, Prospects

SpaceNut wrote:

Re: Fuel Cell Development, Application, ProspectsI remember why I was looking at the water electrolysis Brown gas vehicle injection use as it was during the years when gas was almost $4 a gallon and propane had sky rocketed as well upward.

With the price of gas rising still now at $2.72 a gallon one would hope that it does not keep going up but that does not seem to be the case.

$4 gas is here. Now what?

The average price of a gallon of gas in the United States is now nearly $2.88, according to AAA. That's about four cents higher than it was Monday. Consumers could start driving less, rethinking large purchases and changing their summer travel plans should the national average price near $3.25 per gallon.

The secondary impact is rising food costs and more all of which the last time it did go that high for fuel costs they all did rise but when the cost of fuel fell none of them went down...

It is more important than one might think to keep the cost to all americans for fuels used to stay low as its going to cause ecomonic chaos for sure.

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#50 2019-04-27 21:11:39

kbd512
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Re: Fuel Cell Development, Application, Prospects

SpaceNut,

Practical alternative fuels would create competition for customers and serve to drive prices down.  There's an up-side and a down-side to every solution out there, but cost is always driven by competition for customers.  If we have robust competitive options, prices will go down.  NH3 is a cheaper fuel.  Batteries may one day become a cheaper alternative.  Hopefully Innolith's claimed 1kW/kg batteries are the real deal.  That would make them weight-competitive with combustion engines.  The fabrication method supposedly uses existing industry equipment, thus the cost should be less and vehicles so-equipped should also be range-competitive with combustion engines.  When consumers have three or more comparable options to choose from- Gasoline or Diesel / Ammonia / Lithium-ion, prices will fall.

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