Are hydrogen tanks superior to batteries?

In most of this discussion, we have neglected to talk about the fuel cells, themselves. The title of the thread tries to pretend that hydrogen tanks are equivalent to batteries - they are definitely not the same.

To get electricity from the hydrogen, you have to have a fuel cell. And you have to have a battery.

To get electricity from a battery, you only need to have wire, and a load.

Fuels cells don't last very long, and they would be pricey to replace: https://www.fueleconomy.gov/feg/fcv_challenges.shtml

Fuel Cell Durability and Reliability
Fuel cell systems are not yet as durable as internal combustion engines and do not perform as well in extreme environments, such as in sub-freezing temperatures.

Fuel cell stack durability in real-world environments is currently about one third of what is needed for commercialization. Durability has increased substantially over the past few years from 29,000 miles to 57,000 miles, but experts believe a 150,000-mile expected lifetime is necessary for FCVs to compete with gasoline vehicles.

Cold-weather operation can also be problematic since fuel cell systems always contain water, which can freeze at low temperatures, and must reach a certain temperature to attain full performance. FCVs can now start and operate in sub-freezing temperatures, but there are still some performance concerns.

Finally, contaminants can degrade fuel cell performance and durability, so it is unclear what level of purity of hydrogen and intake air will be required for FCVs to operate reliably in real-world conditions.
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That is from 2009, and I have heard that fuel cells last about 75,000 miles, now.

https://www.iop.org/resources/topic/archive/fuel/
Aren’t they expensive?
Two things have prevented major production of hydrogen-powered cars until now: the cost, and producing the hydrogen in the first place. Until recently, the platinum catalyst that splits the hydrogen into an ion and an electron has been prohibitively expensive.

Up to a few years ago, hydrogen fuel cells cost around $1000 for every kilowatt of power they generated – or around $100,000 per car. There were various avenues of research into how to bring the cost down, including work at Lawrence Berkley Laboratories on replacing the platinum catalyst with a platinum-nickel alloy that was 90 times more efficient.

By last year, US Department of Energy reported that it had got the cost down to $61 per kilowatt – far closer to the target cost of $30. One further possibility being explored by Ballard Power Systems is enhancing the platinum with carbon silk. This is expected to bring a 30% reduction in cost with no loss of performance.
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So, to power the 150kW motor in my Bolt EV, you would need to have about $9,150 to replace the fuel cell about every 5 years. That adds 12.2¢ / mile to the 21¢ / mile you have to pay for hydrogen.
 
Martin Williams said:
Bob. I can't work out whether this simple fuel station uses an HP differential electrolyser or a compressor. Perhaps you know?
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I had no luck finding a system schematic. Perhaps you might contact them and ask?

If you can find another home hydrogen generator for sale, let me know and we’ll recalculate what it does.

Bob Wilson
 
Pushmi-Pullyu said:
Now you are claiming you were not implying that this eliminates the need to provide more energy to compress the gas during generation?
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Of COURSE I am claiming it doesn't eliminate the need to provide the energy! Only a complete cretin would imagine I ever did! I never even mentioned energy on the basis that it was so self-evident that energy IS needed to compress gas however it is done, and also because it was not relevant to the point I was making.

I can't be bothered with addressing the rest of your post, sorry.
 
As to fuel cell durability it has improved considerably according to this:

https://www.nrel.gov/hydrogen/highlight-fcev.html.

If it's correct I think 120,000 miles with a 10% degredation would be very tolerable. That corresponds to about six or seven years of use in my case. I have never kept a car from new for longer than five by which time they begin to show their age, develop rattles, the shock absorbers need replacement etc. etc. and its time to get rid. There is more work being done to extend life too. Here's news of another advance from the University of Delaware.

https://www.sciencedaily.com/releases/2017/09/170905134458.htm

I will, as ever, believe it when I see it deployed, but it certainly looks as if some progress is being achieved in the area. I guess they will cotinue to improve at a decreasing rate for ages, but in my opinion they are already good enough to make a practical car.
 
bwilson4web said:
I had no luck finding a system schematic. Perhaps you might contact them and ask?

If you can find another home hydrogen generator for sale, let me know and we’ll recalculate what it does.

Bob Wilson
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I imagine home hydrogen systems are like hens teeth at the moment, so I will defer looking for ten years or so in the hope that there are more about.

I don't believe Honda's pilot plant was ever intended for home use. Their approach was to make a compact system that could be 100% made in the factory and delivered to site quickly and inexpensively. How it got its electricity was not really their concern although their pilot plant used solar. It was, I think, only designed to supply one car. You have to register with Honda to read their technical journal and it is well worth doing. It is free and I think open to anyone and there are a lots of papers on automotive matters which I think may be of general interest.
 
Pushmi-Pullyu said:
A science denier trying to cast aspersions on someone with a degree in physics, like Elon Musk, comes across as painfully obvious desperation.
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Having a physics degree myself I respect his scientific knowledge. However I was not criticising this. I was not even criticising his defence of his business, indeed I applaud it. As a salesman and a businessman it is his job.

I was, in fact, criticising those people stupid enough to take his opinions about the relative merits of his, versus a competitor's product at face value and believe them.

Again, you are apparently failing to understand plain English. Do try to keep up Pushmi!
 
With petrol of which hydrogen is just a less efficient derivative (petrol would be its fuel stock and given its lower efficiency it would be even dirtier obviating any need beyond pushing a scam and artificial scarcity) annually globally you have to ship something like (very rough guess) 14 Trillion pounds (70000 aircraft carriers) 2000 miles in equivalent fuel stock weight before you can even get to the point of combusting for fuel/energy and then you have to let 2/3 of it go up in heat pollution- that would before a starting gun even went off in a race against green energy . And these are just the beginning of the inefficiencies. This is why green is 7x more efficient than petrol period and the only thing worse than petrol is hydrogen. This is also why petrol has been burning out the US economy and every part of the global economy that isn't going green.

In the US petrol has destroyed the economy and destroyed the standard of living. Average American gets less than half of what they got in 1970 for 4x the productivity plus they have medical bankruptcy, no job security and can't afford education where before it was free they also can't retire and barely afford children or afford to pay off a house where before a single income vice the debt laden 2 incomes was enough, they've lost social mobility and have gone backwards wealth wise across the generations. In the mean time petrol subsidies have increased so that even post nuclear we've never spent more on defense with so much that as hidden petrol subsidies. 400 billion a year in the US alone in petrol subsidies plus all the phony war bailouts has sunk the US economy and standard of living. US has easily wasted $50 trillion in today's dollars on petrol since 1970, impoverishing its people in cumulative way with scam that was meant to hollow out the public sector, and create artificial scarcity to keep an obsolete long ago paid off capital class up at everyone else expense. Its all the Powell memo stuff.
 
Martin Williams said:
In the USA, I believe the number of people in this position is about a third.
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About 1/2 to 2/3 of the US population lives in detached single family homes and would have access to charging at home. And about 1/2 to 2/3 of US households have 2 or more vehicles. There are about 126million US households. That’s roughly 60 million that could easily use an EV today. Problem is one of education. A vast majority of of the public don’t even realize EVs exist, or that charging infrastructure exist, and how convenient it is to have a full “tank” every morning.

For others without easy home charging. They could charge while at work at one of thousands of L2 chargers, or while shopping, eating at a restaurant, going to a movie, or generally going about their day. No need to make a special trip to charge.
 
I received this from iluvscuba. Apparently it was to this thread but seems to have vanished

"Martin said: "As to the production of hydrogen, I suspect that given time it will all come from electrolysis, not methane. Why? Because it is a convenient way of putting excess renewable power to use. In order to get most of your electricity from - say - wind, you have to over-provide in terms of peak power. Basically, you get about 40% of whats on the nameplate so if you aim to get 50% of a years electricity from wind, you will have to install 50% more than you need. This means periods when you have far more power than you need, and the result is wind farms are often shut down in windy conditions. The electricity they provide could be usefully put to work in electrolysing tapwater. "

You are joking right? Do you know how much clean water you need to create enough hydrogen to power all the cars in the world if what you propose happens? Fresh water is an extremely scarce and finite resource on earth, with climate change, there are already prediction from scientist that the plain states and Sask/Man turning into desert within 100 years. The Colorado river is already running dry, millions of people does not have clean drinking water already and yet people like you is still pushing hydrogen that waste water and electricity instead of using renewable energy like wind and solar. Isn't it better to use our resources to provide wind turbine and solar panel to every household instead? "

He can be reassured that every drop of hydrogen produced from water is returned to the environment as water. The whole process is 100% energy neutral.
 
I've just read the whole post and I have to agree with Martin, the others here sound exactly like ice owners saying electric cars r useless..... Calling someone names or rubbishing them just makes u look like a bully, I mean calling someone a foolcell fanboy is no different than a ice owner calling u a socalist greeny.
Yes at the moment it isn't really cost effective or energy effective but it seams to be getting there and martin does have a point of over producing power and why not make it into stored energy
A closed mind is just that
 
Thanks for your support Don. Its good to know that there are people here who prefer debate to cheerleading.

101101 has asked a good question. The answer to it involves mainly cost. Batteries are expensive. Probably, if one is storing energy for general use later, Lead acid would be a better choice - weight and bulk are not important in a fixed installation. A hydrogen installation - particularly if a compressor is not needed - would be less expensive. The cost - per unit of stored energy - of tanks falls with size. It's round-trip efficiency is low of course.

Overall efficiency for a battery solution would be higher, but with the caveat that if you are intending to charge your car from a storage battery, you are losing energy rather faster than you might think. Batteries (Lithium ion phosphate batteries - the most efficient solution for a stationary installation) have a round trip efficiency of about 90%. The inverter to supply it would manage about 95%. You will need a DC-DC converter or something similar to charge your car which will have an efficiency again of 95%. Thus the best you can manage is .95 x 0.9 x 0.95 = 81% In other words, you are losing nearly 20% of the energy.

If you use a lower cost lead acid battery system, then the best you can manage is .95 x .7 x .95 = 63%. You lose 37% of the energy.

It is not often mentioned, but 'fast charging' is very energy inefficient and once you abandon slow constant-current charging for speed, the round trip efficiency plunged dramatically.

However, I make the point once again that if the energy is essentially free, then efficiency may be less important than capital cost.
 
Robert Llewellyn's FullyCharged series details the Orkney Island hydrogen experience:

They chose to generate and export hydrogen in a small semi-trailer. This Orkney Island experiment would be consistent with someone thinking wind-power and solar are 'free' so efficiency doesn't matter. Perhaps in Orkney but if they'd chosen battery semi-trailer or a modular Tesla battery system, their net energy would be about 2x larger. A practical example is the ferry.

A diesel electric, conversion to battery would be trivial. But even the abundance of Orkney wind and tidal power, hydrogen generation and transfer is too inefficient to support replacing the ferry diesel. So the exported hydrogen provides pier power and not a whole lot of that.

Bob Wilson
 
Very interesting. I find Llewellyn rather irritating. He seems to have no scientific knowledge whatsoever which means he can't ask any searching questions and accepts what he's told. Often, this comes from people who have 'skin in the game' and the result is heavily skewed. He is, I understand, heavily subsidised by the EV business, and relentlessly pushes battery cars which probably further explains why awkward questions are rare.

I'm not sure I agree with your conclusion that hydrogen is 'too inefficient' to replace the ferry. What they said was that they were preparing for it when it is time to replace the ship, by training seamen sufficiently knowledgeable about it to handle it safely. I'd imagine it perfectly feasible to look at a hydrogen fuel cell ship. If it can be done for trains, I see no obstacle for ships. I'd be surprised if the ferry were not diesel electric anyway, so half the technology exists!

Orkney is hardly typical of the mass of us who live in a more urban environment, though, so much knowledge gained from trials like this will not be applicable. An example is the wide use of battery cars. On a small island where long journeys are not possible, a decent range is not necessary, and they suit the lifestyle of the inhabitants.
 
I was reading about some designs of the 4th gen reactors running close to salt boiling and have enough heat for hydrogen creation think I read it in wiki about 4th gen reactors, to tired to find link now :)
 
Martin Williams said:
He can be reassured that every drop of hydrogen produced from water is returned to the environment as water. The whole process is 100% energy neutral.
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"Energy neutral"? Seriously? :rolleyes:

Once again you remind everyone that you have absolutely no understanding of even the most basic fundamentals of thermodynamics.

Fuel cell stacks are only about 50% efficient. So right there, at least half of the energy bound up in H2 is converted to waste heat. Of course, several other steps along the way between generation and "burning" in a fuel cell stack contribute to the very wasteful process of using highly compressed hydrogen as fuel for a wheeled vehicle.
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Martin Williams said:
Probably, if one is storing energy for general use later, Lead acid would be a better choice - weight and bulk are not important in a fixed installation.
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Lead-acid batteries are only cheaper than li-ion in the short term. They wear out much faster than li-ion batteries. Those who actually use such systems say that if you have to buy a third set of lead-acid storage batteries -- that is, if you have to replace the original set twice -- then you'd have been better off buying li-ion in the first place.

Martin Williams said:
A hydrogen installation - particularly if a compressor is not needed - would be less expensive.
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Given the low energy content of H2 by volume, how could you ever store enough H2 to be worth bothering with, without at least some compression? A stationary home H2 energy storage system might not -- probably doesn't -- need the very high compression of a fool cell car (5000 - 10,000 PSI), but for a typical installation, there would still need to be some compression involved.

Martin Williams said:
Overall efficiency for a battery solution would be higher, but with the caveat that if you are intending to charge your car from a storage battery, you are losing energy rather faster than you might think. Batteries (Lithium ion phosphate batteries - the most efficient solution for a stationary installation) have a round trip efficiency of about 90%. The inverter to supply it would manage about 95%. You will need a DC-DC converter or something similar to charge your car which will have an efficiency again of 95%. Thus the best you can manage is .95 x 0.9 x 0.95 = 81% In other words, you are losing nearly 20% of the energy.
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As opposed to losing ~50% of the energy in that home H2 energy storage system, and significantly more than 50% if you're using it to power a fool cell car?

How is it that you can possibly think that's a winning argument for you? Once again, I have to wonder if you're just "playing dumb" here.
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DonDeeHippy said:
...I mean calling someone a foolcell fanboy is no different than a ice owner calling u a socalist greeny.
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This is typical of the false claims of equivalency from people promoting an extremist position and trying to make it sound reasonable.

I'm an advocate for electric cars. I don't at all mind if someone wants to call me an "EV fanboy" or a "battery-head". It's what I am; why in the world would I try to deny it? And it's absurd to suggest I'm ashamed of either label; I'm quite proud to be an EV fanboy or a battery-head!

But if you're a fool cell fanboy... well then, I certainly understand why you would be embarrassed at being correctly called that. If I was trying to promote the "hydrogen economy" hoax, I'd be ashamed of myself too!

As far as me being a "socialist"... Well, that's factually incorrect, so again that's just you attempting a false equivalency.

DonDeeHippy said:
A closed mind is just that
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It certainly is. So, if you reject the very clear and very extensive evidence that it is both physically and economically impossible for hydrogen to ever become a practical fuel for general transportation needs, then you've amply demonstrated that your mind is closed on the subject.
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My reasons for not inventing silly names for people whose ideas I disagree with are that it is a childish thing to do.

Awfully simple really.
 
Lead acid cells can be stuck in an unheated well-ventilated outhouse and will tolerate a wide range of temperatures quite well. You can't do that with any lithium batteries, and this is what makes the big difference. Lithium ion cells are not the right cells to use for domestic storage anyway. Lithium ion phosphate are better as they have the best round-trip efficiency. Poorer energy density, but that's not very important in a static application. I expect Musk has foisted lithium ion cells on his powerwall customers simply because he makes them, and they are more compact and therefore saleable, although he may have done the right thing.

Lead acid cells don't require much in the way of natural resources either. they have an excellent recycling infrastructure and almost 100% of the lead is used time after time after time. Horses for courses. The right way to go for domestic storage is undoubtedly lead acid, just as it is for conventional ICEs, submarines and most aircraft.

Actually, you CAN get away without the need for a compressor by using an electrolyser that will tolerate a high pressure between the anode and the cathode. Honda has such a device and I expect so have other companies. In a domestic system, not intended to fill cars, you don't need to worry about maintaining a high pressure. You can let it go up and down according to generation and use.

If you want to charge your car, you need pressure higher than the 70Mpa it is designed for and a tank that is more voluminous than that of the car, but that is something you design for. The electrolyser raises the pressure in your storage tank to maybe 100Mpa and connecting it to the car's tank until it reaches 70Mpa is all that is required. No compressor anywhere in either case.

I can't see how this simple arrangement can, in mass production, work out more expensive than a massive set of batteries (Big enough to store all your car needs as well as your house) kept in about room temperature plus all the high power inverters and dc-dc converters required!

Finally, I repeat that nobody is claiming that the high differential pressure electrolyser doesn't involve energy to effect the compression. It does. In fact it does the job quite a bit more efficiently than a mechanical compressor, but that is not its main advantage. It's biggest advantage is in the elimination of a noisy and expensive component and the system simplicity this offers.
 
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