Hydrogen for transportation

Here in Europe, there’s a massively pro hydrogen lobby. Whenever the Hydrogen high priest or disciples publish articles they’re routinely highly bias, showing no desire to waste words describing the difficult technical issues. So in order to provide some balance, here’s a really difficult issue for hydrogen, atmospheric leakage, indeed its Hydrogen’s dirty little secret ;-

It goes like this;- Hydrogen is the smallest molecule so will diffuse through metal and even glass. A high pressure hydrogen tank will bleed to empty in a little over a week if unused. Hence about 6-12% (depending on storage time) is inherently leaked into the atmosphere.

Now here’s the dirty part;- H2 vented into the atmosphere has a global warming potential (GWP) of 13 to 200;- http://agage.mit.edu/publications/global-environmental-impacts-hydrogen-economy
that’s one ton of H2 in the atmosphere has the same impact as 13-200 tons of CO2. So assuming 2% inherent leakage into atmosphere will come from every ton of hydrogen produced, even if it’s end use turns it 100% into water, just using it will have the same effect of releasing 0.7tons of CO2 (for reference;- one ton of kerosene will produce 2.7 tons of CO2). In order to give some idea of an existing example, the Space Shuttle used only 56% of the hydrogen supplied in total to the program.

By simple examination any claims of hydrogen being zero emissions is deception.
 
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Didn't you posted that elsewhere ? Still make sense, of course.
Just asking in passing - if I put E85 in my very ordinary gasoline-fueled 2011 Fiat, will I shot the engine dead ?
 
I wouldn't recommend it. E85 is mostly ethanol, most manufacturers offer separate models optimized for E85. E85 has a lower energy content than petrol, so you have to inject more of it. Fuel injection systems not designed for E85 will not detect the different fuel composition and I suspect they'll run the engine too lean.
 
Hydrogen ICEs pop up every so often. BMW did a small production run in 2005 (the H7), and had demonstrators as far back as 1978. They have some big drawbacks: engines that develop less power than the same engine running on petrol (in the H7: 50% less power), and a tank that fills most of the boot for a range of half that of the petrol car.
 
Hobbs, not to mention an H2 tank that goes from full to empty in 7 to 8 days even if you don’t drive the car. They don’t mention this in the promotion because that that’s a negative message and with H2 there can be no bad news. Toyota are particularly keen on hydrogen but they’re in an ever shrinking minority.
 
They have some big drawbacks: engines that develop less power than the same engine running on petrol (in the H7: 50% less power),

Waaaaait... I thought hydrogen was (at least) plenty of energy, particularly compared to gasoline ?

Methanol & ammonia are 1/3rd of gasoline energy, itself with 2.5 times less energy than hydrogen... at least that's how I understood it as far as rockets and aircraft are concerned. Ok, IC cars are probably differents.

I thought hydrogen made the I.C engine (or its combustion at least) far more energetic.

What did I missed ?
 
See the Wikipedia article:

Typically hydrogen engines are designed to use about twice as much air as theoretically required for complete combustion. At this air/fuel ratio, the formation of NOx is reduced to near zero. Unfortunately, this also reduces the power output to about half that of a similarly sized gasoline engine.
 
I fully agree with Elon Musk.

Hydrogen economy is a hoax. It has become a sort of religion with a lot of fanatic followers.
Even at universities there are people who believe in it, some are even allowed to call themselves professors.
They fell in the trap when they were young, and years later when they realize that it is nonsense they can't go back on it as part of their funds (from industrie with commercial interests), all their publications, their whole career hangs on it.
They are trapped and have to keep propagating the lie until their retirement.

Hydrogen is merely an energy carrier, not an energy source as the believers claim.
They tell us that there is a huge amount of hydrogen in the sea water so what are we waiting for?
No, the hydrogen in the sea water is there in the form of H2O , not as H2.
To turn H2O into H2 takes a huge amount of energy, but they don't mention that inconvenient truth.

There are some niche applications for hydrogen and fuel cells, for example in space travel, but that is peanuts on the total world energy consumption.

It takes three times as much energy to make hydrogen out of water than that hydrogen will then deliver in a fuel cell.
Therefor hydrogen is not a solution to anything; it does not yield energy but in reality wastes energy.
It merely acts like a battery, but a very lousy one: for every 100 kWh of electricity you put into it you only get 35 kWh out of it.
It can therefor not replace fossil fuels (which are an energy source), but it can only replace other batteries (which are an energy carrier), but only a fool would do that because all batteries are much more efficient than hydrogen.
For comparison: a lithium-ion battery delivers 85 kWh for every 100 kWh that was put into it. That's still a loss of 15 % but that is minor compared to the 65 % loss when using hydrogen.

In the mean time there is a whole industry that hopes to make a lot of money selling useless gadgets to stupid people. Thanks to the enormous amount of nonsense on the internet people become more stupid by the day and therefor the hydrogen economy hoax could go on for years to come.

Now mr. Frans Timmermans from the EU in Brussels also propagates hydrogen. That does not surprise me because already for years mr. Diederik Samsom is his left hand. They are both Dutch and so am I, so I know those two clowns already for many years from Dutch politics. Samsom has always been a hydrogen economy believer and now he seems to have infected his boss too. If there only were a vaccin against hydrogen economy, although that probably would not make a much difference as religious persons usually refuse vaccines.

Timmermans leads the European Commission’s work on the European Green Deal and its first European Climate Law to enshrine the 2050 climate-neutrality target into EU law.
There you have another lie that is propagated by the believers: the lie that hydrogen is green.
How can an energy carrier that loses two-thirds of the original energy be called green?
Hydrogen is not green and neither is any other form of energy carrier or battery; they are just "storage vessels" for energy that already existed before.

It is important to understand the difference between an energy source (fossil fuels, wind, solar, nuclear) and an energy carrier (hydrogen, batteries). To charge the carrier always requires energy from a source.

Before some believer(s) claim that I don't know what I am talking about: I am a chemical engineer with 30 years of experience in design of various petroleum and petrochemical plants, also hydrogen plants, and I have a thorough knowledge of thermodynamics.
 
What do people think about Powerpaste?


Powerpaste is a magnesium and hydrogen -based fluid gel that releases hydrogen when it reacts with water. It was invented, patented and is being developed by Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM) of the Fraunhofer-Gesellschaft in Dresden, Germany.[1][2]

Powerpaste is made by combining magnesium powder with hydrogen in a process conducted at 350 °C and five to six times atmospheric pressure to form magnesium hydride. An ester and a metal salt are then added to make the finished Powerpaste.[2]

When Powerpaste reacts with water it produces hydrogen in a predictable manner for use in fuel cells.[2] The molecular formula of magnesium hydride reacting with water is MgH2 + 2H2O → 2H2 + Mg(OH)2, so half of the produced hydrogen comes from the Powerpaste and half from the water.[1] Magnesium hydroxide (Mg(OH)2) is a residue by-product created by this process.[1]

Fraunhofer claims that Powerpaste is able to store hydrogen energy at 10 times the energy density of a lithium battery of a similar dimension and substantially more than compressed hydrogen at 700 bar and is safe and convenient for automotive situations. [2]

Fraunhofer states that they are building a production plant slated to start production in 2021, which will produce 4 tons of Powerpaste annually.[2] Fraunhofer has patented their invention in the USA and EU.[1]
 
If this research proves correct then gaseous hydrogen is most likely non viable for addressing global warming;-


Potentially each kilogram of hydrogen released into the atmosphere does the same climate damage as 200 kilograms of CO2, which means leakage needs to be less than 4% to even break even. Being such a small molecule Hydrogen is very difficult to stop leaking, it even permeate through metal.
 
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I fully agree with Elon Musk.

Hydrogen economy is a hoax. It has become a sort of religion with a lot of fanatic followers.
Even at universities there are people who believe in it, some are even allowed to call themselves professors.
They fell in the trap when they were young, and years later when they realize that it is nonsense they can't go back on it as part of their funds (from industrie with commercial interests), all their publications, their whole career hangs on it.
They are trapped and have to keep propagating the lie until their retirement.

Hydrogen is merely an energy carrier, not an energy source as the believers claim.
They tell us that there is a huge amount of hydrogen in the sea water so what are we waiting for?
No, the hydrogen in the sea water is there in the form of H2O , not as H2.
To turn H2O into H2 takes a huge amount of energy, but they don't mention that inconvenient truth.

There are some niche applications for hydrogen and fuel cells, for example in space travel, but that is peanuts on the total world energy consumption.

It takes three times as much energy to make hydrogen out of water than that hydrogen will then deliver in a fuel cell.
Therefor hydrogen is not a solution to anything; it does not yield energy but in reality wastes energy.
It merely acts like a battery, but a very lousy one: for every 100 kWh of electricity you put into it you only get 35 kWh out of it.
It can therefor not replace fossil fuels (which are an energy source), but it can only replace other batteries (which are an energy carrier), but only a fool would do that because all batteries are much more efficient than hydrogen.
For comparison: a lithium-ion battery delivers 85 kWh for every 100 kWh that was put into it. That's still a loss of 15 % but that is minor compared to the 65 % loss when using hydrogen.

In the mean time there is a whole industry that hopes to make a lot of money selling useless gadgets to stupid people. Thanks to the enormous amount of nonsense on the internet people become more stupid by the day and therefor the hydrogen economy hoax could go on for years to come.

Now mr. Frans Timmermans from the EU in Brussels also propagates hydrogen. That does not surprise me because already for years mr. Diederik Samsom is his left hand. They are both Dutch and so am I, so I know those two clowns already for many years from Dutch politics. Samsom has always been a hydrogen economy believer and now he seems to have infected his boss too. If there only were a vaccin against hydrogen economy, although that probably would not make a much difference as religious persons usually refuse vaccines.

Timmermans leads the European Commission’s work on the European Green Deal and its first European Climate Law to enshrine the 2050 climate-neutrality target into EU law.
There you have another lie that is propagated by the believers: the lie that hydrogen is green.
How can an energy carrier that loses two-thirds of the original energy be called green?
Hydrogen is not green and neither is any other form of energy carrier or battery; they are just "storage vessels" for energy that already existed before.

It is important to understand the difference between an energy source (fossil fuels, wind, solar, nuclear) and an energy carrier (hydrogen, batteries). To charge the carrier always requires energy from a source.

Before some believer(s) claim that I don't know what I am talking about: I am a chemical engineer with 30 years of experience in design of various petroleum and petrochemical plants, also hydrogen plants, and I have a thorough knowledge of thermodynamics.

Dear God... I knew hydrogen was a bad idea (being a space nerd since the craddle), but to such a point...

In passing, what is your opinion about ammonia ? Is it any better than hydrogen or an equally abysmal idea ?

I often think of hybrid cars (think of a Toyota Prius) with gasoline replaced by ammonia.
-No carbon emissions (no carbon in NH3 nor in lithium batteries)
-Keep the proven IC engine
-Can benefit from advances in lithium battery tech (Tesla)
-range has the best of both worlds: lithium batteries and IC engines, in and out of cities.

-Alternative: a Toyota Prius with the IC engine converted to E85

Why is nobody selling such cars ?
 
The big problem with using ammonia in a combustion engine is that the combustion products are Nitrogen oxides; okay, not greenhouse gases, but bad pollutors instead.


cheers,
Robin.
 
Hydrogen atoms, in all their forms, are smaller than the metal or plastic atoms of the tank that contains it, or the pipes and valves that distribute it. Hydrogen will ALWAYS escape... is that we will never learn the lesson of Hindenburg?
 

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The big problem with using ammonia in a combustion engine is that the combustion products are Nitrogen oxides; okay, not greenhouse gases, but bad pollutors instead.


cheers,
Robin.

NOX is a greenhouse gas about thirty times worse than CO2. NOX will be produced only if Ammonia is burnt in an unsuitable combustor, typically of the type used for other fuel types such as methane.

Now consider that “AddBlue”, the additive used to suppress NOX in diesels, uses Ammonia from decomposed Urea as it’s active ingredient. The urea is introduced into the catalyst where the temperature decomposes it into ammonia which in turn reacts with the NOX to convert it into water and nitrogen.

So to burn Ammonia with an ultra low NOX emission it requires a two stage combustion system, a so called “rich to lean” cycle . This has been demonstrated in a few places now with NOX levels below those of conventional Carbon fuels.
 
The big problem with using ammonia in a combustion engine is that the combustion products are Nitrogen oxides; okay, not greenhouse gases, but bad pollutors instead.


cheers,
Robin.

NOX is a greenhouse gas about thirty times worse than CO2. NOX will be produced only if Ammonia is burnt in an unsuitable combustor, typically of the type used for other fuel types such as methane.

Now consider that “AddBlue”, the additive used to suppress NOX in diesels, uses Ammonia from decomposed Urea as it’s active ingredient. The urea is introduced into the catalyst where the temperature decomposes it into ammonia which in turn reacts with the NOX to convert it into water and nitrogen.

So to burn Ammonia with an ultra low NOX emission it requires a two stage combustion system, a so called “rich to lean” cycle . This has been demonstrated in a few places now with NOX levels below those of conventional Carbon fuels.

Great, thank you for the information guys.

So, hybrid cars with lithium batteries and such ammonia IC engine ""rich to lean" ? Working together, hand-in-hand ?
 
The NOx emissions are not a big problem, since ammonia is the stuff used to reduce NOx emissions in SCR Catalyst. When using a stoichiometric combustion (which makes sense for ammonia as fuel), a simple 3-way catalyst can efficiently reduce the NOx emissions to extremely low values.

NOx describes NO, NO2 and N2O2 and only N2O2 is a greenhouse gas. Combustion engines usually don’t produce N2O2 (laughing gas), but ammonia engines might do (I’m not sure). The greenhouse relevant N2O2 is produced by agriculture, not by combustion.
Ammonia is a much better fuel than hydrogen, because it is at least as efficient and can be stored and transported as simple as LPG.
Using "power to gas technologies" is only useful, if it enables the storage of surplus energy (e.g. from windfarms during a stormy Sunday night) and the transport of energy rich areas in the world to countries as stupid as Germany (which is shutting down the nuclear power when most urgent needed….). Hydrogen unsuited for long time storage and transport because its low density and/or the extremely low temperature (if liquid) requires way to much effort.

I just received an offering for a big hydrogen trailer, it can carry only 360 kg (that’s about as much energy as 1 t of gasoline) and cost 8200 € (being parked for 2 weeks).
 
Recently I wanted to know (because of For all mankind) whether the Shuttle orbiter payload bay could carry a decent quantity of LOX / LH2 to feed one SSME in the back and head to lunar orbit.

It blew my mind that the payload bay (15 ft diameter, 60 feet long) had a volume of 300 cubic meters - and thus (in theory of course !) it could hold 300 metric tons of water... or LOX. Quite a number, even by rocket standards.

And then LH2 entered the picture and ruined the party. Only 15 tons of it took more than 100 cubic meters out of 300.

LOX in contrast is quite close from water density (1.05 or something).

What saved the day was that it takes 6 or 7 LOX to burn 1 LH2 - but even then, balacing their volumes versus masses was a complete nightmare, courtesy of LH2 absurdly low density.

Bottom line: hydrogen low density is complete hell. Most rocket props are reasonably close from water and from 1 (0.8 to 1.45) - but hydrogen is merely 0.2 or 0.25, and thus a giant PITA.

For example, out of 118 metric tons of S-IVB: the stage proper, engine and structure included, was 13 tons: LOX, 87 tons, and LH2 merely 18 tons. Completely unbalanced props.
Yet LH2 took nearly as much voluminous tank as the LOX (at least it greatly helped the case of Skylab).
 
Hydrogen would be a perfect fuel for airships, that’s the only application (no longer in use) where low density isn’t an issue…

Space x will use LNG as rocket fuel, I think this is the best compromise between volumetric/gravimetric density, specific impulse and storing effort. The fuel cost might not be of main concern, but LNG is also much cheaper than hydrogene or any other special rocket fuel.

Ammonia has only halve the gravimetric density of Jet-fuel which is a serious disadvantage for airplanes, but its still way higher than batteries.
 
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Taken from the attached paper;-

“Excess NH3 will then be used to catalytically reduce any NOx left in the exhaust converting it to nitrogen and water.

When the hydrogen is released, there will be an added bonus, Kapat explained. The conversion process also provides cooling, which can be used to keep engines from overheating and burning out. The impact may be better engine performance and efficiency.”

The first paragraph is about low NOX and the second paragraph is how to make up for the lower energy density.
 
Ammonia is a way better choise than hydrogene, but it will take a lot of time until politics will understand that. Hydrogene is not toxic, but it can blure the mind and cause illusions...
 
I can't help wondering... back in '63 the US Army "Mobile energy depot" studied ammonia for aircraft and helicopters. Not cracked, no hydrogen: just plain ammonia. It cut energy in half compared to kerosene; and performance accordingly.

And thus the idea went nowhere. I suppose land and sea vehicles can afford the lower energy, but flying machines... not so much.

Now, that smart trick of "cracking ammonia into hydrogen" - how hard it is to make it happen inside an aircraft ?

In a few words: did anybody ever thought about it before ? 1963, 1973 or 1979 oil shocks ?

Or is it a matter of very recent technological breakthroughs ?
 
Well, ammonia can’t compete with fossil jet-a in terms of cost and energy density, but if you have to find a CO2 neutral fuel it is the most promising option in terms of efficiency and cost. The energy density is only halved that of jet-a, which isn’t bad compared to hydrogen and will make it a good option for many aero applications (not for the military and extreme long-haul traffic). The performance of a turbine or a combustion engine will remain almost unchanged, despite the fuel consumption (in g/kwh) will double.

Unlike hydrogen, a long time storage and long distance transport of ammonia as an energy carrier is feasible, that’s what really matters. For a combustion engine, you don’t have to crack a large amount of ammonia, about 5% is sufficient to speed up combustion for effective use (also ignition by a small quantity of fuel oil will be an interesting option). The main problem is having enough electric energy which can, in my point of view, only be provided with nuclear energy.
 
I can't help wondering... back in '63 the US Army "Mobile energy depot" studied ammonia for aircraft and helicopters. Not cracked, no hydrogen: just plain ammonia. It cut energy in half compared to kerosene; and performance accordingly.

And thus the idea went nowhere. I suppose land and sea vehicles can afford the lower energy, but flying machines... not so much.

Now, that smart trick of "cracking ammonia into hydrogen" - how hard it is to make it happen inside an aircraft ?

In a few words: did anybody ever thought about it before ? 1963, 1973 or 1979 oil shocks ?

Or is it a matter of very recent technological breakthroughs ?

The US 63 effort was trying use nuclear power to do away with a liquid energy logistical supply chain;- fairly typically bold for the time. Helicopters were included and nobody cared how much NOX was dumped into the atmosphere.

In common with a lot of these energy alternative ideas, it comes around when oil supply becomes an issue but rapidly dies as the supply problem is resolved.

Making Ammonia from air, water and hydro electric is not new. This was way all Ammonia was produced in Europe up until the early nineties when cheap natural gas became available.
 
Burning NH3 doesn t produce more NOx than burning hydrocarbone, but it offers plenty residuel NH3 to convert NOx back to N2 and O2. of course, using a SCR catalyst is much easier on a piston engine than on a turbine wich would suffer extremly by the back pressure. You would have to optimize the combustion process inside the turbine somehow.

By the way, the cracking of ammonia with exhaust heat is a way to recover otherwise wasted heat and turn it into chemical energy, so that it inceases the efficiency.
 
The math is simple: Hydrogen has a storage efficiency 3 times lower than batteries. It takes more than 60 kWh to produce 1 kg of hydrogen, which propels a fuel cell vehicle 100 km. That same 60 kWh gets an EV to 300 km.
 
The vast majority of hydrogen available today releases more CO2 than that of just burning the methane it was generated from. So anyone using it now is doing more damage to the atmosphere than a gasoline (petrol) engine which is hardly a good selling point for your wealthy eco worrier.

Given the atmospheric damage inherently produced by supply infrastructure leakage, it’s between 11 and 200 times worse per unit mass than CO2, I’d be surprised if hydrogen gets a serious foot hold in energy supply…. Not currently a popular narrative.
 
Fuel cells are a better match to hydrogen than an ICE: total efficiency of the propulsion system is higher.
Even then, they're not that good compared to their ICE counterparts. They're heavier, use up more hydrogen for a similar power, and there is still the hydrogen leakage problem to deal with. People will have to use ICE engines until micro-fusion engines are available. Unless they want to use LNG-powered fuel cells.
Hydrogen would be a perfect fuel for airships, that’s the only application (no longer in use) where low density isn’t an issue…

Space x will use LNG as rocket fuel, I think this is the best compromise between volumetric/gravimetric density, specific impulse and storing effort. The fuel cost might not be of main concern, but LNG is also much cheaper than hydrogene or any other special rocket fuel.

Ammonia has only halve the gravimetric density of Jet-fuel which is a serious disadvantage for airplanes, but its still way higher than batteries.
If you've got nuclear lightbulb engines, water ends up being the best propellant. LNG has a major carbon fouling problem.
 
Fuel cells are a better match to hydrogen than an ICE: total efficiency of the propulsion system is higher.
Even then, they're not that good compared to their ICE counterparts. They're heavier, use up more hydrogen for a similar power, and there is still the hydrogen leakage problem to deal with. People will have to use ICE engines until micro-fusion engines are available. Unless they want to use LNG-powered fuel cells.
Hydrogen would be a perfect fuel for airships, that’s the only application (no longer in use) where low density isn’t an issue…

Space x will use LNG as rocket fuel, I think this is the best compromise between volumetric/gravimetric density, specific impulse and storing effort. The fuel cost might not be of main concern, but LNG is also much cheaper than hydrogene or any other special rocket fuel.

Ammonia has only halve the gravimetric density of Jet-fuel which is a serious disadvantage for airplanes, but its still way higher than batteries.
If you've got nuclear lightbulb engines, water ends up being the best propellant. LNG has a major carbon fouling problem.
The thermodynamic efficiency of fuel cells is usually forty to sixty percent (https://www.linquip.com/blog/efficiency-of-fuel-cell/). The best ICEs -- low-speed diesels -- are the only ICE to break 50% (and are better than steam plants); most small ICE are under 40%.

Of course, production of hydrogen is quite energy-intensive, and, while there are extensive industrial uses for it, the sort of network needed for its use in aviation does not exist. There are wires everywhere there's civilization, so batteries don't require that sort of infrastructure be made.
 
Fuel cells are a better match to hydrogen than an ICE: total efficiency of the propulsion system is higher.
Even then, they're not that good compared to their ICE counterparts. They're heavier, use up more hydrogen for a similar power, and there is still the hydrogen leakage problem to deal with. People will have to use ICE engines until micro-fusion engines are available. Unless they want to use LNG-powered fuel cells.
Hydrogen would be a perfect fuel for airships, that’s the only application (no longer in use) where low density isn’t an issue…

Space x will use LNG as rocket fuel, I think this is the best compromise between volumetric/gravimetric density, specific impulse and storing effort. The fuel cost might not be of main concern, but LNG is also much cheaper than hydrogene or any other special rocket fuel.

Ammonia has only halve the gravimetric density of Jet-fuel which is a serious disadvantage for airplanes, but its still way higher than batteries.
If you've got nuclear lightbulb engines, water ends up being the best propellant. LNG has a major carbon fouling problem.
The thermodynamic efficiency of fuel cells is usually forty to sixty percent (https://www.linquip.com/blog/efficiency-of-fuel-cell/). The best ICEs -- low-speed diesels -- are the only ICE to break 50% (and are better than steam plants); most small ICE are under 40%.

Of course, production of hydrogen is quite energy-intensive, and, while there are extensive industrial uses for it, the sort of network needed for its use in aviation does not exist. There are wires everywhere there's civilization, so batteries don't require that sort of infrastructure be made.
My understanding of fuel cells is that they continue the 'hydrogen is horrible for anything less than fusion or antimatter (i.e., atomic reactions)' trend. Also, last I've heard, fossil fuel-powered fuel cells are better than hydrogen ones (the best equivalence I've heard is 'our fossil fuel-powered fuel cells are a (GURPS) tech level higher than their hydrogen-powered counterparts).

Also, batteries have their own problems (especially in terms of disposal) in comparison.
 

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