Zubrin is not an honest interlocutor in this issue, though the basic message is probably sound. Examples of his dishonesty:
1) The price argument. Hydrogen will generally be more expensive than gasoline; his argument about current prices is like making an argument about gasoline before it was a widely used industrial product.
2) The delivery argument: this doesn't even begin to make sense. Straw man argument where he claims it couldn't be delivered efficiently in the domains he suggests. It is harder to deliver hydrogen than hydrocarbons, but the numbers he quotes are just garbage.
3) Limiting the vehicle storage to compressed gas (muh hindenberg) and cryo. No serious people really talk about this to my knowledge. Metal hydrides (https://en.wikipedia.org/wiki/Hydrogen_storage#Metal_hydride...) are the way hydrogen probably would be transported in a hydrogen economy. It's still less efficient volumetrically than hydrocarbons, but then so is everything else. The argument that it must be as dense as hydrocarbons is just goalposting. People like electric cars just fine, and the batteries they use are 100x less efficient in energy density. At least at one point, the envisioned hydrogen economy was you just retrofit hydride "gas tanks" to existing internal combustion machines. If you can make everything else work, that's a fairly reasonable thing to do. Which is probably why Zubrin never mentions it.
4) Fuel cells; yes, these are very hard to do for a consumer product. They are amazingly cool though, and they should still be invested in. I think this is Zubrin's biggest fear. His goalposting about fuel cell efficiency is silly: so what if they're not more efficient on some measurement than an ideal diesel motor? They don't smell as bad either.
Zubrin is a neocon type who works in the defense industry. For all we know this could have been commissioned by some oil company types, or maybe he's just being cussed. I don't disagree with the over all message though. You'd have to change a lot of major infrastructure to make hydrogen work for a portable energy source.
Agree with most of your points. There are some valid observations that he then smoothly extrapolates to invalid conclusions.
There has been considerable progress in fuel cell vehicles, for example. The Honda Clarity fuel cell version has an estimated 360+ mi (US EPA) range: https://www.caranddriver.com/reviews/a15096419/2017-honda-cl... . Fill times are significantly better than current high-rate battery electric vehicle charging.
It seems to me the key will be in whether we make advancements faster in higher energy-density batteries vs. scale up of direct hydrogen production (e.g., https://solarfuelshub.org/192301-vapor-fed-cells ) . Electrolysis using grid power probably does not make sense. It would be valid to question, even if we could directly scale up hydrogen production from renewable sources, wouldn't it make more sense to use the same area for electricity production? If we're talking about ground transportation, the only advantages would be in range and fill time of FCVs over BEVs. Simplicity strongly favors BEVs over FCVs.
Hydrogen combustion for ground transportation (although neat!) just does not seem compelling. It will take a lot of plumbing refits, fuel injector changes, ECU recalibration, etc. to make an existing IC car burn hydrogen. And if you're designing from scratch, why continue the burden of using an Otto cycle reciprocating machine over fuel cells?
Absent compelling reasons to do otherwise (which the Zubrin article does not present), it seems like continuing the research relevant to BEVs and renewable hydrogen production on parallel paths is the prudent thing to do.
Random fact: gasoline was initially a waste product of producing kerosene - essentially free.
So yes prices of gasoline went up once it started being widely used.
IMO the storage and transportation issue is what kills hydrogen. Also compression losses are nontrivial.
Assuming we need to manufacture fuel in renewable way methane or ethanol sounds like good ways to go. Both can be done in scale by abusing bacteria/algee.
Overall I want my car to just have a standard form factor "power unit" and swap it out to whatever the new hotness is.
> Zubrin is a neocon type who works in the defense industry. For all we know this could have been commissioned by some oil company types, or maybe he's just being cussed. I don't disagree with the over all message though. You'd have to change a lot of major infrastructure to make hydrogen work for a portable energy source.
This credibility attack doesn't wash at all. Zubrin is a conservative thinker, yes, but he's not a spokesperson for the defense industry. He is a staunchly independent aerospace consultant whose project is humans-to-Mars. He's actually worked against industry interests since his plans are vastly less profitable than the cost-plus boondogles the traditional industry lobbies for (SLS, etc.).
I think he might be speaking outside his element here, but I also think the date (2007) is very important. This was back in the middle of the worst parts of the Iraq war, with rising oil prices. Oil we got then was mostly from the middle east. People felt we needed to get off oil for economic and national security reasons, not because of climate change per se. The predictable result was blue-sky research into the hydrogen economy on things that really couldn't be deployed at that time (and still are barely deployed now, 12 years later). Zubrin's argument at the time, which this essay is a part of, was that we should switch to "flex fuel" engines which can take diesel or biofuels. Then we wouldn't be dependent on the sweet crude from the middle east.
Now, in 2019, most of the oil we get is from relative friendlies in Canada and Venezuela, and we have better refineries for converting poor-quality crude from these sources into gasoline for cars. Improved battery efficiencies driven by mobile phones and notebooks have made electric storage for cars actually feasible. Solar efficiencies make locally produced energy economically viable. In short, energy world in 2019 looks nothing like 2007, and I don't think this article is very interesting at this point in time.
Robert Zubrin is a visionary, who I'm sure wouldn't compromise his credibility to churn out some paid-propaganda.
I guess your objections are otherwise pretty reasonable, except the metal hydrides part is unfair for a 2007 article. The Toyota Mirai and other extant hydrogen vehicles store hydrogen, not metal hydrides.
Do hydrides have any advantages at all over synthetic hydrocarbons or biofuels? It seems like an effort to shoehorn hydrogen in there somewhere instead of just admitting that it has literally no place at all in the energy economy
Is that a problem, though? CO2 emissions aren't locally toxic. The main issue with it today is the fact that the carbon comes from the ground and doesn't get put back. Water vapor is a greenhouse gas too!
Water vapor is a greenhouse gas, but it is always kept in balance and the air cannot hold more than it is. All that will happen is that it rains. And no amount of water vapor from hydrogen cars compares to what all the oceans contribute to the water vapor. It will basically have no effect.
Right, I wasn't actually suggesting that water vapor emissions from hydrogen vehicles would be a climate issue - on the contrary, I was drawing the comparison to illustrate that greenhouse gas emissions aren't necessarily a problem, if part of a closed loop (or other stabilizing influences like you point out).
Entropy. It's easier to just not involve carbon at all via some hydrogen cycle than to burn it and have to capture it, or extract it from the air/water.
As I mention elsewhere in this thread, hydrocarbons will dominate the air travel industry long after most others have converted. The less carbon in flux, the better.
Is it easier, though? Both hydrogen and carbon cycles react atmospheric oxygen with some other element, creating a low-energy molecule that is released into the environment. To be sustainable, the feedstock atom must be segregated from that same waste low-energy molecule, an inherently energy-intensive procedure. This energy must be sustainably sourced by either nuclear or energy ultimately from the sun. Separating hydrogen from water requires electricity, a very low-entropy form of energy. Creating combustible carbon from atmospheric CO2 is as simple as planting something that grows fast - it will use sunlight directly. And that's not even getting in to how much more tractable carbon is to work with than hydrogen.
Really, it doesn't matter whether we burn hydrogen or carbon. How much carbon is in flux is irrelevant. The main thing - the only thing - is to stop digging it up. The cycle must be closed. After that, it's safe to let the market decide the most efficient energy cycles.
The problem we face isn't fuel storage and delivery, it's waste disposal. "Hydrogen economy" advocates miss that point entirely. Moving and transporting hydrogen gas is a total dead end, and I can't believe that hydrides would be much better.
I've always thought that the best approach would be to find a way to take advantage of the hydrogen delivery infrastructure that already exists in the form of gas stations on every other corner. If we could just come up with a scalable way to split hydrocarbon molecules without actually burning them, we'd be able to turn most CO2 emission sources into harmless water sources. Might as well wish for flying cars and unlimited fusion power while I'm at it, I guess...
Reminds me of the theoretical concept of a "digester" of hydrocarbons which kept the carbon and other toxic wastes like say heavy metals bound into a "slag" instead of releasing it atmospherically.
Granted by the time we could manage something like that there would be far better options out there including using excess power generation to synthesize fuel from the air and water - let alone batteries which may use the energy more efficiently.
> the batteries they use are 100x less efficient in energy density.
How is this measured? Are you saying that a gasoline car has 100x the range of an EV car with a battery volume equal to the gas tank's volume? That seems excessive.
It's virtually impossible to beat hydrocarbons for chemical potential energy density. Diesel is the most dense commonly available such fuel. You put a liquid in a tank and move the complexity to the heat engine (which is 20-50% efficient depending on the size of the motor). Batteries don't even come close. Which is why if you put a fuel tank in a tesla with 1200lbs of gasoline in it (about 170 gallons), and operated it at comparable performance, its range would be considerably longer, despite lack of woo like regenerative braking and more efficient electric motors.
It's one of the things Zubrin is complaining about in his mendacious article. Fair complaint; "gee the periodic table won't cooperate" -though metal hydrides are not terrible either, and in conjunction with fuel cells (potentially 100% efficient, despite his saying "nuh uh"), could be considerably better than a hydrocarbon car.
Wait, are you telling me that someone who complains about backwards Islamic cultures and government wasting money before he even starts addressing his main point is not completely fair and impartial?! Colour me surprised. The use of emotional language and pejoratives almost had me convinced it was a genuine science article!
(Whether he is right or wrong on those points is not important here; they're completely unrelated to the main point of the article, and that he goes off on those tangents reveals a lot about the author and his intentions, IMHO).
I nearly closed the article after reading his off-topic intro. I was expecting to read about hydrogen, not a rant about other cultures. It really detracts from the quality of the article.
I do have to wonder whether this was intentional, though. The author appears to be targeting the government administration at the time. He's buttering them up by starting with a rant with which they're likely to agree. I'm not sure that it was intentional, but if it was, it was a smart move.
No, you misread that. It's not the author breaking out into a rant. That illustrated the rhetoric used in the hydrogen pitch given by Bush post 9-11. The idea was to drum up hydrogen as a way to fight terrorism and radical islam which was being funded by oil. (edit: clarify)
> The price argument. Hydrogen will generally be more expensive than gasoline; his argument about current prices is like making an argument about gasoline before it was a widely used industrial product.
Hydrogen is a widely used industrial product. The comparison is totally sound. The hydrocarbons for gasoline are readily drilled out of the ground. Hydrogen needs to be manufactured either from these hydrocarbons (which is pointless for fuel, you can just use the hydrocarbons directly) or via electricity (which is far more expensive).
A mass market for carbon could not reduce the price below that of its inputs. Even if we had abundant cheap electricity it's unclear that hydrogen would really be economical against all alternatives.
> People like electric cars just fine, and the batteries they use are 100x less efficient in energy density.
He's comparing fuels, you're comparing batteries to fuels, which doesn't make sense.
> Fuel cells; yes, these are very hard to do for a consumer product. They are amazingly cool though, and they should still be invested in.
So the six billion dollars of investment mentioned aren't enough?
> Zubrin is a neocon type who works in the defense industry.
This habit of putting people into ideological boxes inhibits your ability to make rational assessments.
> For all we know this could have been commissioned by some oil company types, or maybe he's just being cussed.
You must have overread the part where he argues for ethanol fuel as a means to break up OPEC.
> I don't disagree with the over all message though. You'd have to change a lot of major infrastructure to make hydrogen work for a portable energy source.
That's not the message though. The message is "it doesn't work, period" and "it is a hoax". I'm not in the position to say that his calculations are right or wrong, but given the lack of progress on hydrogen as a fuel, it's probably not far off the truth.
I agree with Zubrin that the hydrogen economy is rather silly and said so. I disagree with virtually all of his reasons and calculations as to why, and many of them are extremely deceptive. It's almost like he doesn't think anyone else knows anything about chemistry.
>>Hydrogen is a widely used industrial product. ...
twenty million metric tons of hydrogen a year made from natural gas versus a couple billion of gasoline made from oil; not comparable at all for the suggested economic uses of hydrogen as a fuel. If hydrogen were used, it would be produced in a different way. Otherwise people could just burn the natural gas.
People invested more than 6 billion in fracking. Fuel cells are promising, and of course I compare fuel cells and the proposed hydrogen economy to batteries; they're used to store energy.
I loathe war mongering neocons, and Zubrin absolutely is one and as such has discredited himself as any kind of policy wonk who expects to be listened to by serious people. That said, some of his martian speculations are amusing, and I might even have an amusing conversation if I were in the same room with him, where the more prominent ones (Bill Kristol) I would be in danger of clubbing to death like a baby seal.
I think the article's issues with hydrogen as a small-vehicle fuel have mostly been borne out -- one thing that seems to have happened since 2007 is that battery technology has gotten a lot better, and electric cars are proving to be a practical solution for a lot of use-cases.
But the article seem to condemn Hydrogen as any part of any zero-carbon economy because of this, as though any energy medium unsuitable for cars is automatically disqualified entirely from the green economy. I can imagine other use-cases where Hydrogen actually works well.
In large vehicles, for example, where a heavy reinforced tank isn't as much of a liability, like maybe a locomotive.
The use of hydrogen as an energy-storage medium for large stationary power plants also seems reasonable, maybe a solar power plant could split water when sunlight is abundant, and recombine it in the fuel-cell when energy-demand is high, using hydrogen storage to bridge the gap.
Or, similarly, a nuclear plant could split water at an efficient, steady "base-load" rate, and recombine it at different rates to match demand.
Viewed as an industrial-scale energy-storage medium, it makes more sense. It still has to compete with other industrial-scale energy storage media, but it's a very different landscape from vehicle fuels.
Hydrogen storage in underground caverns is not only feasible, it's actually practiced in several places around the world.
Hydrogen's place is for rare times when renewables or short term storage can't do it. This is the last 10-20% of the electrical power market, the part nuclear fans seem to harp on (even though nuclear would be terrible for filling it also.) For such rare uses fuel cells would be inappropriate; gas turbines would be better (even if the round trip efficiency were lousy.)
Hydrogen is only useful as 'short term storage' of energy.
So whether or not Hydrogen is useful really boils down to whether or not hydrogen is a superior source of energy storage versus Lithium batteries, compressed air, flywheels or whatever.
> This is the last 10-20% of the electrical power market
It's not the 'last 10-20% of the electrical power market'.
What renewables like solar and wind can't cover, without effective energy storage, is 100% of the power requirements 30-40% of the time.
Solar only works when the sun is shining. Wind mills only work when the wind is blowing at a appropriate speed. Unless you produce a massive excess of energy and then store it somewhere then neither of these two technologies can ever replace traditional power generation.
The best you can can achieve otherwise is to have solar power during the bright hours of the day and then massive number of natural gas turbines to pick up the slack the rest of the time.
Traditional power generation plants are a poor match with renewable because they can't vary their output quick enough to match the wildly variable capacity of solar and wind.
So the important part of the question is whether or not hydrogen is a useful mechanism to store the energy. And so far it has not been.
"Hydrogen is only useful as 'short term storage' of energy."
This is exactly backwards. It is only useful for long term storage. For short term storage, other alternatives would more efficient and economically superior.
Hydrogen's advantage is that huge quantities of it can be stored underground, at very low cost. Hydrogen can act as a literal rainy day energy fund, and to smooth over seasonal differences in energy production and use.
My take on energy storage is this: Ultimately, hydrogen is more scalable than almost any other energy storage method, save sodium/air batteries (if we can figure that out) and using electric vehicles as batteries (dependent on consumer behavior to scale).
- lithium has scarcity issues which will only get worse with electric vehicles
- liquid batteries likewise require some more rarer elements, corrosive enough to require
- underground storage (of air pressure, CO2, etc) requires caverns/mines on site
- pumped hydro has even tighter site constraints
- biofuel/synfuel is decent for mid-to-long term storage, but slow to generate
- flywheel has energy density issues
Hydrogen, your main limits are basically steel for tanks, and some rare metals in catalytic amounts.
There hasn't been enough incentive in energy storage deployment to push the scaling up and costs down. But I think we are closest to an "embarrassingly parallel" deployment of hydrogen as energy storage.
Lithium comprises only a very small fraction of the mass of Li-ion batteries. The resource constraints are on other elements, like cobalt, used in the electrodes. Lithium could become much more expensive without greatly affecting the economics of Li-ion batteries.
It's pretty clear that hydrogen-powered automobiles are not going to be a thing -- electric batteries work very well for that use case. There are some cases where I think hydrogen might still work better than the alternatives.
The most obvious one is aviation. There are a few battery-electric aircraft flying today but they have very short range. I don't think there's any conceivable battery chemistry that will allow anywhere near the range of hydrocarbon-powered aircraft.
However, liquid hydrogen has much greater energy density than hydrocarbon fuels. It's also quite difficult to work with. But when you're talking about a vehicle the size of a 737 (much less an A-380), the economics might ultimately be favorable.
It would probably require aircraft models specifically designed for liquid hydrogen -- the tanks are so large that the aircraft will have to be designed around them. That's probably a major impediment to adoption. It's possible that biofuels or synthetic fuels made from CO2 will instead replace fossil fuels in aviation, instead.
The additional costs related to cryonics, aerodynamic drag, safety issues, and material embrittlement mean that liquid hydrogen will never be a viable commercial aviation fuel. It seems attractive in theory but ends up being totally impractical when you get into real world details.
The way forward is absolutely going to be battery power for short flights and synthetic liquid hydrocarbons for longer distances.
Totally agree. Airliners have a fuel fraction (fuel wt / total wt at takeoff) around 50%. Half the gross weight of the entire system is fuel. And that's with liquid, room-temp, atmospheric pressure fuel that's easy to transfer and can fit into every liquid-tight nook and cranny. Furthermore, you can pump it around for weight trim.
I don't see hydrogen in any form, including hydrides, meeting these criteria. Not to mention, the entire distribution infrastructure is tooled out for liquid hydrocarbons.
Synfuel is expensive compared to fossil fuel, but not dramatically so.
You're currently looking at ~$0.64/L for FF jet fuel, ~$0.95/L for biodiesels, and $1.15/L for fully synthetic fuels eg Fischer-Tropsch.
> Half the gross weight of the entire system is fuel.
That's true for jet propellant, but it's not true for hydrogen. A hydrogen powered airplane would have to have a much greater volume than an equivalent airplane fueled with regular jet fuel, but it would have substantially less weight. I'm not sure how this would work out for overall performance, though -- you'd have substantially more direct drag to overcome, but on the other hand you'd have a lot less lift-related drag simply because you'd need a lot less lift.
As a thought-experiment, you could imagine an aircraft roughly the size and shape of a 757 but with the weight and payload capacity of a 737. This might be an acceptable design for a cargo carrying aircraft, but realistically, a passenger-carrying aircraft would need large cylindrical tanks on the wings for safety reasons, but also with increased drag.
> Not to mention, the entire distribution infrastructure is tooled out for liquid hydrocarbons.
In the specific case of hydrogen-powered commercial aviation, this doesn't matter at all, because there would not be a distribution infrastructure, at least as we generally think of it. Instead, we'd need to distribute water and electricity to airports, and the hydrogen would be produced and stored on-site. The equipment to make and store liquid hydrogen wouldn't necessarily be cheap, but over any significant period of time it would likely be dominated by the cost of electricity necessary to produce the hydrogen through electrolysis.
The economics of synthetic fuels for aviation are probably still better, but I think that it might be a lot closer than people imagine. If you could cheaply retro-fit existing airframes for hydrogen they'd be a lot closer still, but I don't think that's likely. It's an interesting possibility to think about though.
> realistically, a passenger-carrying aircraft would need large cylindrical tanks on the wings for safety reasons, but also with increased drag.
Precisely. Any weight savings of energy density per wt of hydrogen are offset by the poor energy/volume, plus the need for cylindrical tanks for stress reasons. Wing fuel tanks are roughly wing-shaped, meaning no increase to cross section. Hydrogen would require sets of cylinders, which add walls which add weight yet don't directly aid the engineering constraints, or exist outside the current flight envelope, adding drag.
Maybe some big advancement in construction methods could allow synergy of hydrogen tanks walls with aircraft structure, but you are still stuck with 1/3rd volumetric density of energy, meaning larger cross section, more drag, and more fuel usage.
Hah. It’s really quite fascinating to see how the tides have turned on alternate fuels. I wonder if the alternative battery tech will materialize or if we’ll look back on that with a similar chagrin.
Oh, plus thousands of words, with numerous arguments, detailed calculations, examples, and formulas, for why hydrogen doesn't work.
But don't let that affect your bias towards the article, or god forbid, temp you to at least keep the former (anti-hydrogen arguments) and ignore the former (ethanol push).
That's the same confusion the article rails against. Methanol and ethanol are no more a source of energy than (terrestrial) hydrogen is. They just might be more convenient fuels, energy carriers.
Hyrodgen can play a huge role in energy storage in a green economy. Creating and storing hydrogen for later use, like when a solar farm is idle at night; as it likely has a surplus during the day, is a common problem with all energy grids.
Of course it can play a role in energy storage in a green economy. But the piece outlines a number of disadvantages it has versus other forms of energy storage. An electrolysis-fuel cell round trip is only around 33% efficient and the capital costs are pretty high. If you want grid storage batteries, potential energy storage, or all sorts of things work better. If you need a fuel you can synthesize from the air for a vehicle that can't use batteries then ethanol or methane are better bets from a storage perspective.
Gasoline powered internal combustion engines average around 20% efficiency, cutting edge new stuff still doesn’t really break 40%. Need to keep that in mind! Yes, gasoline itself is very energy dense, but that doesn’t mean we efficiently use it in automobiles.
Amusingly lithium is also really energy dense too. The difficulty is it's only 2-3% of the battery by weight. Upside of that is there is a lot of room for improvement. Not that it's easy low hanging fruit though.
For transport hydrogen suffers a lot of the same issues as lithium. The storage systems are all heavy. Compare with an empty gasoline tank you can lift with one hand.
In terms of energy efficiency in powering moving vehicles then yes, hydrogen is as energy efficient as anything else. That's why I complained about it's energy density rather than its efficiency in that context. In terms of grid storage batteries are ~99% efficient and pump storage is 75% efficient.
I think the big boost for hydrogen this time around will be production from natural gas with carbon storage. It allows us to decouple how quickly we wind down natural gas production from how quickly we decarbonize, and that is a killer solution.
Production from natural gas using steam methane reforming plus water gas shift reaction is how 95% of the worlds hydrogen is made. After these processes, one must anyways separate out the CO2, to make the H2 usable. This is done at industrial scale, hundreds of billions of standard cubic metres every year. Mostly the CO2 is just released, but increasingly it is caputred and stored.
The technology is easily scalable to meet demand, in fact it has to scale far less than how much battery production has to scale from current levels.
I'm convinced it's not a question of if, but a question of when this becomes a major thing. We're at the point where we need all the technological and societal mechanisms we can muster.
I haven't heard anyone seriously suggesting hydrogen as a surplus storage mechanism. Do you have any examples of this, examples of pilot plants or whatever? Most I've seen are discussing using molten salt to directly store heat from during the day which can be used to power turbines over night.
Are we just going to ignore the fact that hydrogen cars exist now in California, they work, the fuel is affordable, and the efficiency is fine?
Hydrogen is useful as a solve for the energy storage problem in green energy. For example, excess solar energy can be stored as hydrogen fuel. Also this solves the "fuel quickly" problem for people who need to drive long distances.
Yes we should ignore those. They are compliance vehicles sold only to satisfy CARB rules and are not otherwise economically viable. Most of the hydrogen is created from natural gas, which means zero reduction in greenhouse gas emissions. Yes in theory hydrogen could be created by electrolysis with renewable energy, but the efficiency is so low as to make it pointless.
Considering the number of such stations, explosions are rather rare, although one did recently explode in the USA. It turns out to be difficult to get a decent explosion out of bulk liquid petrol. Even setting it on fire is not as easy as some think. Try it with liquid diesel, practically inert. What you really need for a good time is empty petrol tanks.
If it exploded; the outcome would have been pretty much the same, but i'm probably wrong. I assume the amount of KJ is about the same; hydrogen will blow up much faster and much more violent. Petrol tend to "wooooof" into an fireball and expell a lot of the energy in the fire afterwards.
A leak in the petrol tanks at a station won't cause explosions in itself, it causes polluted ground water. Not to mention it's quite hard to get petrol to blow up, you need a pretty specific mix of fuel and air.
Hydrogen pretty much blows up no matter what if there is a leak.
German bit is still part of the great scam. Their green biomass fuel plants are co-firing wood pellets(sourced from chopped forests) together with brown coal in order to whitewash coal power plant into carbon neutral biomass plant.
This scam nation has today produced between 6-9 GW which is roughly between 12 and 18 percent of the total consumption with wind and water. You are right to pick on brown coal where use has not decreased much but other coal and fossil fuels have.
Too many people commenting who have absolutely no idea nor knowledge about how hydrogen works or anything related to it. Plus: the old "efficiency" argument should go out of the window altogether and be replaced by an "environmental impact" argument.
1) The price argument. Hydrogen will generally be more expensive than gasoline; his argument about current prices is like making an argument about gasoline before it was a widely used industrial product.
2) The delivery argument: this doesn't even begin to make sense. Straw man argument where he claims it couldn't be delivered efficiently in the domains he suggests. It is harder to deliver hydrogen than hydrocarbons, but the numbers he quotes are just garbage.
3) Limiting the vehicle storage to compressed gas (muh hindenberg) and cryo. No serious people really talk about this to my knowledge. Metal hydrides (https://en.wikipedia.org/wiki/Hydrogen_storage#Metal_hydride...) are the way hydrogen probably would be transported in a hydrogen economy. It's still less efficient volumetrically than hydrocarbons, but then so is everything else. The argument that it must be as dense as hydrocarbons is just goalposting. People like electric cars just fine, and the batteries they use are 100x less efficient in energy density. At least at one point, the envisioned hydrogen economy was you just retrofit hydride "gas tanks" to existing internal combustion machines. If you can make everything else work, that's a fairly reasonable thing to do. Which is probably why Zubrin never mentions it.
4) Fuel cells; yes, these are very hard to do for a consumer product. They are amazingly cool though, and they should still be invested in. I think this is Zubrin's biggest fear. His goalposting about fuel cell efficiency is silly: so what if they're not more efficient on some measurement than an ideal diesel motor? They don't smell as bad either.
Zubrin is a neocon type who works in the defense industry. For all we know this could have been commissioned by some oil company types, or maybe he's just being cussed. I don't disagree with the over all message though. You'd have to change a lot of major infrastructure to make hydrogen work for a portable energy source.