The arguments for EVs over Hydrogen fuelled cars

[siteguru]

Er.... Not the whole story. The tank farm near Heathrow is fed by pipelines from one or two refineries (can't recall which ones - I've been asleep several times since I had dealings with the project but I think Stanlow was involved).

Essar (formerly Shell) Stanlow is moving into carbon capture and storage (using the estuary where oil/gas has been extracted), and also Blue Hydrogen - these are their current big investment/research areas.

 

[tsedge]

Er.... Not the whole story. The tank farm near Heathrow is fed by pipelines from one or two refineries (can't recall which ones - I've been asleep several times since I had dealings with the project but I think Stanlow was involved).
Fuel is then distributed to the aircraft stands via a pipework and hydrant system, which is why you don't see endless fuel tankers on the apron.

I found all this out when I got involved many years ago. The Heathrow Hydrant Company wanted to upgrade their control systems and metering (needed bloody accurate and repeatable meters for pressure too. As well as needing fiscal accuracy flow metering, they tested for leaks by shutting in sections of pipeline and watching for pressure drops).

We quoted for the project but didn't get it, unfortunately, as it had looked like a fun one.

The whole enterprise was divvied up with one company running the tankage, another the pipeline's and another the hydrants, iirc. All designed so the money went round and round too fast for the tax man to siphon off very much.

60% of the aviation fuel is delivered by rail to the tank farm. This is a deliberate initiative to reduce the use of road tankers.

 

[turntoport]

I'm glad it is but all of the evidence suggests it wont work, cant work for very good reasons. JCB are promoting their Hydrogen powered plant but it really has nowhere to go. Very frustrating really, as a fuel being burned it's great with only water as it's emission, it's just getting it, storing it and transporting thats the slight problem.

As the Hindenberg reminds us...

 

[MoDolph]

If we want to decarbonise long haul travel the only options are liquid hydrogen or synthetic aviation fuel. A lot of the characteristics of liquid hydrogen that make it unsuitable for ground transport don't apply to aviation.

It might have less volumetric energy so it'll require fuel tanks ~4x the size but it's energy density by mass is 2.8x higher so it's a lot lighter.

It boils off over time so you wouldn't want it in your car but planes are always fuelled immediately before takeoff and only fly for a limited time. It's also much colder at altitude (-50°C) so the loss is reduced.

We already have the technology to handle cryogenic liquids in lightweight craft as used in rockets, all we need is new aircraft designs to handle the extra volume.

 

[johnb80]

If we want to decarbonise long haul travel the only options are liquid hydrogen or synthetic aviation fuel. A lot of the characteristics of liquid hydrogen that make it unsuitable for ground transport don't apply to aviation.

And some that dont apply to ground transport affect aviation badly.

It might have less volumetric energy so it'll require fuel tanks ~4x the size but it's energy density by mass is 2.8x higher so it's a lot lighter.

But the tanks to contain it are more than a little heavier.

A Boeing 747 carries 184000kg of kerosene, it would need about 70,000kg of Hydrogen for the same energy. The fuel tank weight to carry this hydrogen is circa 400,000 kg pretty much the total weight of a fully laden 747.

It boils off over time so you wouldn't want it in your car but planes are always fuelled immediately before takeoff and only fly for a limited time. It's also much colder at altitude (-50°C) so the loss is reduced.

How do you deal with the extra weight of the tanks?

 

[MoDolph]

A Boeing 747 carries 184000kg of kerosene, it would need about 70,000kg of Hydrogen for the same energy. The fuel tank weight to carry this hydrogen is circa 400,000 kg pretty much the total weight of a fully laden 747.


How do you deal with the extra weight of the tanks?

I think your getting confused between pressurised storage Vs cryogenic storage.

An Ariane rocket tank weighs 5.5 tons and contains 28 tons of liquid hydrogen. They are only 1.3mm thick.

 

[Gadget Geek]

Liquid helium for MRI scanners is supplied in lightweight vacuum dewers which can be wheeled into a passenger lift as they are so light. I would imagine similar vacuum tanks could be fitted into airplane wings.

 

[johnb80]

I think your getting confused between pressurised storage Vs cryogenic storage.

No, not really, how long is a rocket fuelled and in the earths atmosphere? It's literally minutes before it's in space at very low temperatures of around -270 degC
It needs to be at -250 degC, a much lower temperature than the -50 deg at 30,000 ft

An Ariane rocket tank weighs 5.5 tons and contains 28 tons of liquid hydrogen. They are only 1.3mm thick.

Yep, but this is a very different application to an aircraft that stay in the earths atmosphere and still doesn't address the fact that Hydrogen takes 3 x the amount of energy to extract it than it creates when used.

Liquid helium for MRI scanners is supplied in lightweight vacuum dewers which can be wheeled into a passenger lift as they are so light. I would imagine similar vacuum tanks could be fitted into airplane wings.

Not quite, Hydrogen needs to be stored in a tank with a pressure of 10,000 psi, not a 260 psi for helium. The lightweight wouldn't be so lightweight for Hydrogen. There are also other issues, the tank shape for pressure storage would be spherical or cylindrical, would not utilise the wing profiles shape make tank capacity reduced whereas it actually needs 3 x the amount of Hydrogen.

 

[Skippy]

Volumetric density is another issue. To house enough hydrogen to power the thing you have to take up most of the space where the people and things go.

I appreciate that it’s not a perfect example: rockets might not weigh much but they are huge.

 

[johnb80]

Volumetric density is another issue. To house enough hydrogen to power the thing you have to take up most of the space where the people and things go.

I appreciate that it’s not a perfect example: rockets might not weigh much but they are huge.

Yep, Toyota had a ICE car conversion, look at the tanks

 

[Skippy]

Yep, Toyota had a ICE car conversion, look at the tanks

View attachment 19810

This is also why a Toyota Mirai is larger and heavier than a Tesla Model 3 LR, but has less interior and boot space. And that’s for a FCEV which is more efficient than any form of combustion.

 

[tsedge]

It is amusing to hear such certainty about hydrogen not being suitable for aircraft.

Existing storage technologies will already work for smaller aircraft, the challenge is the big jets (where most of the pollution is).

With all the money pouring in to this area, the chances of breakthroughs are high.

The battery technology also does not exist for large electric jets, so we seem to be comparing vapourware to vapourware.

I don't know which technology will win out but it is surely unwise to conclude that because neither can do it today, one of the technologies is a clear winner.

 

[johnb80]

It is amusing to hear such certainty about hydrogen not being suitable for aircraft.

Existing storage technologies will already work for smaller aircraft, the challenge is the big jets (where most of the pollution is).

With all the money pouring in to this area, the chances of breakthroughs are high.

The battery technology also does not exist for large electric jets, so we seem to be comparing vapourware to vapourware.

I don't know which technology will win out but it is surely unwise to conclude that because neither can do it today, one of the technologies is a clear winner.

At this point in time we cant get Hydrogen at anything like economic prices compared to Jet fuel. We cant easily store it either, it simply will not happen unless these two major obstacles are sorted.
Existing storage for small aircraft are a huge success? have you seen many operating? I accept that electric flight may not be the answer BUT there are many electric aircraft in operation here and now, the same cannot be said for Hydrogen.

 

[tsedge]

At this point in time we cant get Hydrogen at anything like economic prices compared to Jet fuel. We cant easily store it either, it simply will not happen unless these two major obstacles are sorted.
Existing storage for small aircraft are a huge success? have you seen many operating? I accept that electric flight may not be the answer BUT there are many electric aircraft in operation here and now, the same cannot be said for Hydrogen.

John, I've already given you a link to a commercial hydrogen plane. It is happening, whether you believe it or not.

There are indeed small electric aircraft with a 30 minute range and all the disadvantages of the heavy batteries having to be lugged up into cruise altitude and then landed again.

At this point in time, electric planes will simply not happen unless the two major obstacles of energy density and battery cost are sorted.

You see? It is easy to rubbish one side.

 

[Gomev]

At this point in time we cant get Hydrogen at anything like economic prices compared to Jet fuel. We cant easily store it either, it simply will not happen unless these two major obstacles are sorted.
Existing storage for small aircraft are a huge success? have you seen many operating? I accept that electric flight may not be the answer BUT there are many electric aircraft in operation here and now, the same cannot be said for Hydrogen.

I think the key words are 'At this point in time'.

The same was said about electric cars when they only had a range of 80 miles(ish), the same is still being said about the charging infrastructure at this time it is not ready for 2030, well of course it's not, 'cos obviously it's 2023.

Personally I don't think there is much of a future for hydrogen, but progress can be rapid when necessity and/or demand requires it, as demonstrated by the battery technology.

So I'm not ruling anything in and I'm not ruling anything out......at this point in time.

 

[Gadget Geek]

I think we have to go back to basics on this discussion.

Hydrogen is being promoted as the answer to . . . well, everything, by oil producers so they can continue making their profit at the expense of the climate.

We do not yet have enough renewables on the grid to produce the excess generation needed for electrolysis of water to produce green hydrogen, which is the only colour of hydrogen which would make the whole thing workable. Otherwise you are just wasting money and energy in an inefficient process to produce a fuel which is less dense than that which you started with. Madness!

 

[johnb80]

John, I've already given you a link to a commercial hydrogen plane. It is happening, whether you believe it or not.

Of course it's happening, huge benefit IF the two major obstacles are sorted.

Looking around zeroavia, one of the links you provided, this was reported

"
The work at ZeroAvia and Airbus has aroused a lot of interest, but not everyone in the aviation industry is convinced hydrogen will play a major role in a transition towards low or zero carbon flight.

There is the question of whether hydrogen can be produced at scale and at a competitive price without itself having a large carbon footprint
The disadvantages start with the physics and chemistry. Hydrogen has higher energy by mass than jet fuel, but it has lower energy by volume. This lower energy density is because it is a gas at typical atmospheric pressure and temperature. The gas needs to be compressed or turned into a liquid by cooling it to extremely low temperatures (-253C) if it is to be stored in sufficient quantities. "Storage tanks for the compressed gas or liquid are complex and heavy," says Finlay Asher, a former aircraft engine designer at Rolls-Royce and founder of Green Sky Thinking, a platform exploring sustainable aviation.

And there are other challenges. The energy density of liquid hydrogen is only about a quarter of that of jet fuel. This means that for the same amount of energy it needs a storage tank four times the size. As a consequence, aircraft may either have to carry fewer passengers to make space for the storage tanks, or become significantly larger. The first option, which applies to Airbus's first two concept planes, would mean a reduction in ticket revenue, other things being equal. The second option, embodied in Airbus's third concept, requires a bigger airframe, which is subject to more drag. Further, an entire new infrastructure would need to be put in place to transport and store hydrogen at airports.

In addition, there is the question of whether hydrogen can be produced at scale and at a competitive price without itself having a large carbon footprint. The great majority of hydrogen used in industry today is created using fossil fuel methane, releasing carbon dioxide as a waste product. Hydrogen can be produced from water through a process called electrolysis, driven by renewable power, but this process is currently expensive and requires large amounts of energy. Only about 1% of hydrogen is produced this way at present."
Im certain on Dragons Den, they'd all be out on this one.

There are indeed small electric aircraft with a 30 minute range and all the disadvantages of the heavy batteries having to be lugged up into cruise altitude and then landed again.

Not absolutely true, BAE have an aircraft Zephyr S its solar powered and has been airborne for 26 days! Rolls Royce ACCEL is a 300mph, 200 mile range aircraft.

DHL have 12 of these on order, all electric!

At this point in time, electric planes will simply not happen unless the two major obstacles of energy density and battery cost are sorted.

Proof of the pudding etc etc

You see? It is easy to rubbish one side.

I'm not rubbishing any side here, I'm simply stating that Hydrogen has seemingly insurmountable problems.

I think the key words are 'At this point in time'.

And that is all I've been saying

The same was said about electric cars when they only had a range of 80 miles(ish), the same is still being said about the charging infrastructure at this time it is not ready for 2030, well of course it's not, 'cos obviously it's 2023.

And its developing fast, my local town Gainsborough, had 2 charge points 2 years ago, now we have 19.

Personally I don't think there is much of a future for hydrogen, but progress can be rapid when necessity and/or demand requires it, as demonstrated by the battery technology.

Necessity is the mother of invention. The problem is H2O the Hydrogen has a very strong link to the oxygen, it needs energy to break it, a lot of energy. A relatively small amount of energy is given off when the link is reformed either in a fuel cell or by burning it, about 1/3. Thats the major issue.

So I'm not ruling anything in and I'm not ruling anything out......at this point in time.

Me neither, never have, open minded but lots of people claim Hydrogen is the saviour, ICE engines are easily converted (they're not) and all in the garden is rosy.

 

[Gadget Geek]

The Rt Hon Grant Shapps, Secretary of State for the Department for Energy Security and Net Zero;

"Hydrogen is the answer . . . Now, what was the question?"

 

[Robf]

Essar (formerly Shell) Stanlow is moving into carbon capture and storage (using the estuary where oil/gas has been extracted), and also Blue Hydrogen - these are their current big investment/research areas.

Project is called hynet. This particular hydrogen process does produce a lot of carbon waste. They are piping it into the depleted liverpool bay hydrocarbon reservoirs along with carbon from a nearby concrete factory and a few other manufacturing processes.

About HyNet - HyNet

HyNet North West is the UK’s leading industrial decarbonisation cluster. It is an ambitious and viable part of the answer to reducing our carbon emissions across multiple sectors of the economy.

hynet.co.uk

 

[Gadget Geek]

How efficient is carbon capture and storage?

Most carbon capture technologies aim to stop at least 90% of the CO2 in smokestacks from reaching the atmosphere. But as the technology approaches 100% efficiency, it gets more expensive and takes more energy to capture additional CO2.

climate.mit.edu