Class 60 to be converted to steam

[edwin_m]

There have been a few - wikipedia lists them
Burning hydrogen to create steam seems like the most inefficient possible way to move a train. Fuel cells are far more efficient, and they are stupid idea until widespread green hydrogen is a thing

Hydrogen-oxygen steam generators (A form of hydrogen external combustion engine.) are theoretically more efficient than hydrogen internal combustion engines and hydrogen fuel cells meaning they could be cheaper to operate, though as it is most theoretical at the time being and railway hydrogen projects have been mostly disappointing in the past it is wise to be cautious about claims about its use on the railways.

But have to wait and see if the economics are any better than for other hydrogen-based fantasies. Wonder how big the hydrogen and oxygen tanks would need to be to give the loco any decent range?

The size of the tanks seems to be one of the big issues for hydrogen power. This one needs an oxygen tank too, which would be about half the internal volume of the hydrogen tank if the pressure is the same, but would have its own separate pressure vessel so would increase the fuel storage volume by more than 50%. So it would have to be a lot more efficient than a fuel cell to get a longer range with the same fuel storage volume, and to outweigh the extra energy needed to compress the oxygen as well as the hydrogen.

In the 1960/70s the original APT and TGV prototypes were designed with gas turbines but went into production with electric power.

Off-topic, but a few gas turbine trains did make it into series production and operation. The French had several fleets of multiple units and sold a few to Amtrak, and Union Pacific had some turbine locomotives. Gas turbines are fine on reasonably constant demand in a power station or an aircraft, but proved to be very inefficient in the railway environment where demand fluctuates much more. The fuel price rises after the 1974 oil crisis pretty much put an end to any further production.

I can't say whether this turbine idea would be similarly inefficient in the same application, but I suppose with several available one or more could be shut down rather than running all of them at below their optimum speed.

 

[Yew]

It is a actually 4 gas turbines powered by Hydrogen just not well described as such creating mass confusion.

Hydrogen powered gas turbines may be more reasonable than heating, turbin-ing, and recirculating water. 2.3 Mw is a relatively reasonable size for modern compact gas turbines, and the generated steam from combustion would probably further improve efficiency.

The size of the tanks seems to be one of the big issues for hydrogen power. This one needs an oxygen tank too, which would be about half the internal volume of the hydrogen tank if the pressure is the same, but would have its own separate pressure vessel so would increase the fuel storage volume by more than 50%. So it would have to be a lot more efficient than a fuel cell to get a longer range with the same fuel storage volume, and to outweigh the extra energy needed to compress the oxygen as well as the hydrogen.

There is oxygen in the air?

Off-topic, but a few gas turbine trains did make it into series production and operation. The French had several fleets of multiple units and sold a few to Amtrak, and Union Pacific had some turbine locomotives. Gas turbines are fine on reasonably constant demand in a power station or an aircraft, but proved to be very inefficient in the railway environment where demand fluctuates much more. The fuel price rises after the 1974 oil crisis pretty much put an end to any further production.

I can't say whether this turbine idea would be similarly inefficient in the same application, but I suppose with several available one or more could be shut down rather than running all of them at below their optimum speed.

Turbine-electric drive trains are much better suited to varying loads than a mechanical linkage, do we know if these historic examples used electric motors?

 

[sprinterguy]

Depending on the rescue locomotive, obviously. That’ll likely be the only time it covers any distance on a main line!

Yeah, that's true. Definitely one of those "I'll believe it when I see it" sort of projects.

 

[JLH4AC]

There is oxygen in the air?

The atmosphere contains nitrogen which lowers the efficiency of burning hydrogen and reacts with oxygen to form NOx thus using pure oxygen removes the need for a selective catalytic reduction system.

Turbine-electric drive trains are much better suited to varying loads than a mechanical linkage, do we know if these historic examples used electric motors?

Union Pacific GTELs were Gas turbine-electric locomotives.

 

[edwin_m]

The French RTG turbo trains would appear to have had hydraulic transmission.

 

[hwl]

Hydrogen powered gas turbines may be more reasonable than heating, turbin-ing, and recirculating water. 2.3 Mw is a relatively reasonable size for modern compact gas turbines, and the generated steam from combustion would probably further improve efficiency.

You need to swap "substantially" for "probably".

This is a very high temperature hydrogen GT with steam heat recovery not a steam turbine system.

The multiple turbines are there to cope with varying power loads that come in rail usage, rather than single big one that wouldn't cope with the variability.

There is oxygen in the air?

Turbine-electric drive trains are much better suited to varying loads than a mechanical linkage, do we know if these historic examples used electric motors?

The atmosphere contains nitrogen which lowers the efficiency of burning hydrogen and reacts with oxygen to form NOx thus using pure oxygen removes the need for a selective catalytic reduction system.

Using pure O2 instead of O2 in air will increase the steam temperature by 600-900C and do wonders for the direct turbine efficiency measurements.

 

[Yew]

You need to swap "substantially" for "probably".

This is a very high temperature hydrogen GT with steam heat recovery not a steam turbine system.

Apologies, I was thinking more that the byproduct of burning hydrogen is water vapour. In old turbojets water was sometimes injected into the combustion chamber to increase thrust, and it is possible we may see some of the same benefit for free.

The multiple turbines are there to cope with varying power loads that come in rail usage, rather than single big one that wouldn't cope with the variability.

That seems sensible, I was just pointing out that a turbine-electric system is less susceptable to these issues than a direct-drive one.

Using pure O2 instead of O2 in air will increase the steam temperature by 600-900C and do wonders for the direct turbine efficiency measurements.

Unless the hydrogen burns significantly cooler than regular gas or oil, which I could see due to the byproduct being water vapour, a substance with a high latent enthalpy of evaporation; I imagine that you'll melt your power turbine.