JCB develops hydrogen combustion engine and outlines plans for the future of propulsion

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Hydrogen is a pants molecule to use as a form of energy howsoever you want to paint it. What improvements have been made in electrolysis? The yield and energy in vs that out was still pants from what I have read recently. Generating electricity is a hideously inefficient process (40% would would be good going in anyone's book), using that electricity to then generate hydrogen is going to be painfully bad once you go and burn it in an internal combustion engine which sends half the energy involved straight out of the exhaust.

Sorry, missed this one. I think the big PEM systems are in the 50-60% efficiency range now, no one cares about the efficiency of electricity production for these anymore as it will have to be from renewables anyway, it just means that it will have to be made somewhere in the world with good access to water and renewable energy but limited local need for the electricity (or water).

You then need to ship the H2 or convert it into something else and ship that.

 

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And "Blue Hydrogen" seems to be a total fossil fuel industry scam

I really disliked that video to start with, but I found it well worth watching right through - thanks for sharing it.

Whilst I'm not sure that I agree with the concept of blue hydrogen, as with most things it's not quite a scam it's just poorly regulated. The fugitive methane emissions piece is the most controversial I think (I'm not sure the oil industry outside the US would agree with the 3.5% leakage number used), but it's too high even at 0.1% so needs to get sorted if this will ever take off.

It's also the reason that CNG vehicles have never really taken off.

 

[Cowabunga]

I work on development of diesel injection systems for heavy duty goods vehicles. Direct hydrogen injection is the future in this field. A development race is on, now that the decision has been made. Exciting stuff.

Do you reckon it’ll actually become mainstream? I’m still sceptical about where this will be used. Is it cryogenic storage or just high pressure?

JCB are fairly convinced that hydrogen is the only viable option for heavy vehicles and industrial plant, which will eventually include tractors. The engines are relatively simple and are basically spark ignition.
Producing it from zero carbon energy is one of the main issue which needs to be resolved but molten salt thorium reactors may be one of the long term solutions.

 

[forblue]

Duracell have the answer.

 

[Robin2020]

Do you reckon it’ll actually become mainstream? I’m still sceptical about where this will be used. Is it cryogenic storage or just high pressure?

Just high pressure. Yes the real attraction with direct in injection is that the OEMs do not need to make major changes to their engines. This is obviously a massive saving. The main decision at the moment is how to control the valves inside the injectors. 2 options being backed at the moment. Similar tec to Volvo gas/diesel hybrid trucks.

 

[Username_Required]

If it's similar to the fumigated trucks, I take it that it still uses a "diesel" pilot to ignite the hydrogen? I take it that you'll still need an SCR to cope with the NOx for EU7? That'll be a challenge.

 

[Cowabunga]

If it's similar to the fumigated trucks, I take it that it still uses a "diesel" pilot to ignite the hydrogen? I take it that you'll still need an SCR to cope with the NOx for EU7? That'll be a challenge.

A spark plug is what an engine designed to only run on hydrogen needs to ignite and combust.

 

[Username_Required]

A spark plug is what an engine designed to only run on hydrogen needs to ignite and combust.

I don't think these engines were originally designed for hydrogen, if they're doing DI then they might as well run a compression ignition mode and get the efficiency benefit.

 

[Cowabunga]

I don't think these engines were originally designed for hydrogen, if they're doing DI then they might as well run a compression ignition mode and get the efficiency benefit.

If compression ignition is possible with hydrogen it must be a more manageable fuel than petrol, where I only know of one smallish engine that mixes compression and spark ignition. Direct injection petrol engines are, apart from that one, 99% of the spark ignition type.

 

[Username_Required]

If compression ignition is possible with hydrogen it must be a more manageable fuel than petrol, where I only know of one smallish engine that mixes compression and spark ignition. Direct injection petrol engines are, apart from that one, 99% of the spark ignition type.

That's the skyactiv-g? That's more controlled auto-ignition, than just compression ignition though.

All diesels are compression-ignition. Hydrogen is a right pain in a pre-mixed engine (whether SI or CI) as it just burns too quickly and can easy fall into run-away pre-ignition/knock. You normally have to use a lot of diluent (air or EGR) to slow the combustion down, but that will limit your peak torque - and potentially your efficiency.

The honda ARC250 was the first SI engine in production with deliberate mid-range HCCI to help sort out it's emissions, that was a two stroke though. Nissan and Toyota both had duel mode engines in the 90s, the Modified Kinematic and Unibus engines respectively. Lots of the first CR diesels used to slip into an HCCI-like mode during motorway cruising, but that wasn't intentional, just a very low NOx mode.

This was going to be a big thing in the 90s, pretty much every university with an engines department was studying how to get gasoline HCCI working properly. Didn't really ever take off.

Really interesting topic though.

 

[Cowabunga]

That's the skyactiv-g? That's more controlled auto-ignition, than just compression ignition though.

All diesels are compression-ignition. Hydrogen is a right pain in a pre-mixed engine (whether SI or CI) as it just burns too quickly and can easy fall into run-away pre-ignition/knock. You normally have to use a lot of diluent (air or EGR) to slow the combustion down, but that will limit your peak torque - and potentially your efficiency.

The honda ARC250 was the first SI engine in production with deliberate mid-range HCCI to help sort out it's emissions, that was a two stroke though. Nissan and Toyota both had duel mode engines in the 90s, the Modified Kinematic and Unibus engines respectively. Lots of the first CR diesels used to slip into an HCCI-like mode during motorway cruising, but that wasn't intentional, just a very low NOx mode.

This was going to be a big thing in the 90s, pretty much every university with an engines department was studying how to get gasoline HCCI working properly. Didn't really ever take off.

Really interesting topic though.

Yes, the Mazda Skyactive G but mostly the Skyactive X with its spark controlled compression ignition.

 

[Username_Required]

Yes, the Mazda Skyactive G but mostly the Skyactive X with its spark controlled compression ignition.

When people were trying to get gasoline HCCI to work stably in the 90s (before exhaust gas recompression was used) spark-assisted compression ignition was seen to be a good halfway house - it didn't offer the full NOx benefit of full HCCI but you could still run throttle-less and it extended the low-load operating window (which was the key for vehicle homologation testing back then). There are quite a lot of interesting engines, particularly in motorsport, that have made use of SACI since then.

Hyundai were going to launch a mixed mode gasoline engine about 10 years ago, I'm not sure if it ever happened.