Universal Hydrogen And Railway Locomotives
On the product page of the Universal Hydrogen web site, there is a section, which is entitled Other Transportation Applications, where this is said.
Our lightweight, aviation-grade modular hydrogen capsules can be used in a wide range of transportation applications where weight, safety, and speed of refueling are important. We are working with partners in automotive, heavy equipment, maritime, and railroad domains. If you have an application that can benefit from our global modular green hydrogen distribution network, please get in touch!
I believe that the railway locomotive of the future will be hydrogen-electric. And so do some of the UK’s rail freight companies, judging, by some of their press releases.
- It would have an electric transmission. like most locomotives today, such as the UK’s Class 66, Class 68, Class 70, Class 88, Class 93 and the upcoming Class 99 locomotives.
- It will be able to use 25 KVAC overhead electrification, where it exists.
- Hydrogen-power will be used, where there is no electrification.
The lowest-carbon of the locomotives, that I listed, will probably be the Class 99 locomotive.
- Thirty have been ordered by GB Railfreight, from Swiss company; Stadler.
- The locomotives will be built at Valencia in Spain.
- It will have up to 6 MW, when running using electrification.
- It will have up to 1.6 MW, when running using a Cummins diesel, with a rating of 2,150 hp.
- Because a proportion of UK freight routes are electrified, it is likely that these locomotives will substantially reduce carbon emissions for many locomotive-hauled operations.
It should be noted that Cummins are heavily into hydrogen and their philosophy seems to embrace families of engines, which are identical below the cylinder head gasket, but with appropriate cylinder heads and fuel systems, they can run on diesel, natural gas or hydrogen.
I wouldn’t be surprised to find out that the Class 99 locomotive will have a diesel engine, that has a hydrogen-powered sibling under development at Cummins.
With perhaps a power on hydrogen of about 2.5 MW, these zero-carbon locomotives would be able to handle upwards of ninety percent of all heavy freight trains in the UK.
These are further thoughts.
Alternatives To Cummins Hydrogen Internal Combustion Engines
There are two main alternatives, in addition to similar engines from companies like Caterpillar, JCB, Rolls-Royce mtu and others.
- Fuel cells
- Gas-turbine engines.
Note.
- Universal Hydrogen and others have fuel cells, that can probably deliver 2.5 MW.
- Universal Hydrogen use Plug Power fuel cells.
- Rolls-Royce have developed a 2.5 MW electrical generator, based on the engine in a Super Hercules, that is about the size of a typical beer-keg. I wrote about this generator in What Does 2.5 MW Look Like?.
Cummins may be in the pole position with Stadler, but there are interesting ideas out there!
Cummins have also indicated, they will build hydrogen internal combustion engines at Darlington in the UK.
Would One Of Universal Hydrogen’s Hydrogen Capsules Fit In A Railway Locomotive?
These are various widths.
- Class 66 locomotive – 2.63 metres.
- ATR72 airliner – 2.57 metres.
- DHC Dash-8 airliner – 2.52 metres
- Class 43 power car – 2.74 metres
I suspect that even if it was a bit smaller a hydrogen capsule could be made for a UK locomotive.
How Big Is The Market?
The UK has around five hundred diesel railway locomotives.
Heart Aerospace Unveils New Airplane Design, Confirms Air Canada And Saab As New Shareholders
The title of this post, is the same as that of this press release from Heart Aerospace.
These are the first two paragraphs of the press release.
Swedish electric airplane maker Heart Aerospace today unveiled significant design updates to its first electric aircraft and confirmed Air Canada, one of North America’s largest airlines and Saab, the Swedish aerospace and defense company, as new minority shareholders.
The new airplane design, called the ES-30, is a regional electric airplane with a capacity of 30 passengers and it replaces the company’s earlier 19-seat design, the ES-19. It is driven by electric motors powered by batteries, which allows the airplane to operate with zero emissions and low noise.
And this is a visualisation of the aircraft from Heart Aerospace..
It looks fairly normal, except that it has four electric engines instead of two turboprops.
This paragraph of the press release gives details of the engine configuration.
The airplane will also include a reserve-hybrid configuration, consisting of two turbo generators powered by sustainable aviation fuel. The reserve-hybrid system is installed to secure reserve energy requirements without cannibalizing battery range, and it can also be used during cruise on longer flights to complement the electrical power provided by the batteries.
Note.
- The slightly larger Dash 8-100 aircraft seats just under forty and has 2.7 MW of installed power.
- Rolls-Royce have a 2.5 MW hybrid turbo generator that runs on sustainable aviation fuel.
- Honeywell have a similar smaller hybrid turbo generator, based on the auxiliary power unit of an Airbus A 350.
I’m sure that Heart can find the hybrid turbo-generators they need for the ES-30.
This paragraph of the press release gives details of the performance.
This gives the airplane a fully electric range of 200 kilometers, an extended range of 400 kilometers with 30 passengers, and flexibility to fly up to 800 kilometers with 25 passengers, all-inclusive of typical airline reserves.
Eight hundred kilometres is sufficient range to serve Bordeaux, Frankfurt, Geneva, Hamburg, Inverness, Paris and Shannon airports from London City Airport.
The press release also discloses that the company has received 96 letters of intent for the aircraft and expects that the in-service date will be 2028.
I don’t think that the date is unreasonable.
Rolls-Royce Makes Duisburg Container Terminal Climate Neutral With MTU Hydrogen Technology
The title of this post, is the same as this press release from Rolls-Royce.
This is the first sentence.
Rolls-Royce will ensure a climate-neutral energy supply at the container terminal currently under construction at the Port of Duisburg, Germany.
There is also this Rolls-Royce graphic, which shows the energy sources.
It would appear batteries, combined heap and power (CHP), grid electricity, hydrogen electrolyser, hydrogen storage and renewable electricity are being brought together to create a climate-neutral energy system.
- As the graphic was named hydrogen technology for ports, I would assume that this is a Rolls-Royce mtu system that will be deployed at more than one port around the world.
- Note the H2 CHPs in the graphic. Could these be applications for Rolls-Royce’s beer keg-sized 2.5 MW electrical generator based on a Super Hercules engine?
- One of Rolls-Royce’s small modular nuclear reactors could be ideal for a large port outside Germany.
This is the last paragraph of the press release.
“Hydrogen technology is no longer a dream of the future, but hydrogen technology will prove itself in everyday use in Duisburg. The parallel use of fuel cell solutions and hydrogen engines shows that we have taken the right path with our technology-open approach to the development of new solutions for the energy supply of the future,” says Andreas Schell, CEO of Rolls-Royce Power Systems.
Rolls-Royce mtu appear to be very serious about the possibilities of hydrogen.
Is The Alstom Hydrogen Train Powered By A Fuel Cell?
In Alstom And Eversholt Rail Sign An Agreement For The UK’s First Ever Brand-New Hydrogen Train Fleet, I mentioned that Alstom’s Hydrogen Aventra could be powered by either a small gas turbine or a fuel cell or cells, but I didn’t plump for one or the other. I said this.
If you look at the proportions of the Alstom hydrogen train and the pictures of Class 710 trains, I feel that the Alstom train could have the longer twenty-four metre cars.
It may be a tight fit compared to creating the Alstom Coradia iLint hydrogen train, but I would feel it is possible to install a fuel cell or cells, the required cooling and the hydrogen tanks, having seen cutaway drawings of hydrogen-powered double-deck buses on the Wrightbus web site.
Interestingly, the Alstom press release doesn’t mention fuel cells, so could the train be powered by a small gas turbine?
I think it is unlikely, but it is technically feasible.
I had forgotten one important factor. Both the Aventra factory and Rolls-Royce are in Derby and I know from talking to a retired British Rail engineer, that there is a lot of contact between the two companies at an informal level.
Rolls-Royce have published this picture of their beer keg-sized generator.
Would it need the cooling system, which appears to be needed with a fuel-cell?
The Rolls-Royce Advantage
There would surely be advantages in using a Rolls-Royce gas turbine to power the train.
- Having a Rolls-Royce power unit must help sales of your plane or train.
- There is the Derby connection.
- Alstom already deal with Rolls-Royce subsidiary; MTU for diesel engines for freight locomotives.
Could we be seeing a hydrogen multiple unit powered by a gas turbine?
What Does 2.5 MW Look Like?
This press release on the Rolls-Royce web site is entitled Rolls-Royce Generator Delivered For Most Powerful Hybrid-Electric Propulsion System In Aerospace.
This Rolls-Royce picture shows the generator installed on a test bed.
These are the first three paragraphs of the press release.
The generator that will be at the heart of the most powerful hybrid-electric aero power and propulsion system in aerospace has arrived for installation at our specialist testbed.
The generator, and related power electronics, was delivered to the newly-renovated Testbed 108 in Bristol, UK, from the Rolls-Royce facility in Trondheim, Norway, having completed an extensive development test programme. It will form part of the 2.5 megawatt (MW) Power Generation System 1 (PGS1) demonstrator programme, for future regional aircraft. In addition to hybrid-electric propulsion, the generator could also be used as part of a “more-electric” system for larger aircraft or within future ground or marine applications.
PGS1 forms an important element of our sustainability strategy, which includes developing innovative electrical power and propulsion systems.
I must say that as an engineer this 2.5 MW generator really excites me, as I see so many possibilities.
- I am fairly certain, that the generator can be powered by hydrogen, to create a true zero-carbon power generator.
- Rolls-Royce mention aerospace, ground and marine applications.
- The physical size must be an advantage, when it comes to some applications.
- The gas-turbine technology at the heart of the generator has been well-proven in the Lockheed Super Hercules.
But I do note in the press release that there is no mention of hydrogen or rail for which the generator must be eminently suitable.
- Rolls-Royce subsidiary; mtu are one of the leading companies, who power large rail locomotives.
- 2.5 MW is ideal for many rail locomotives.
- The small size must help integration into a rail locomotive.
- My calculations show that the generator and a hydrogen tank could be fitted into a typical modern rail locomotive.
- As electric transmissions can be used, the locomotive could also use electrification.
A lot of these arguments would also apply to the very large trucks used in the mining industries and ships of various sizes.
Conclusion
This Rolls-Royce 2.5 MW Generator will have lots of applications.
Will Zero-Carbon Freight Trains Be Powered By Battery, Electric Or Hydrogen Locomotives?
These are a few initial thoughts.
We Will Not Have A One-Size-Fits-All Solution
If you consider the various freight and other duties, where diesel locomotives are used, you get a long list.
- Light freight, where perhaps a Class 66 locomotive moves a few wagons full of stone to support track maintenance.
- Intermodal freight, where a Class 66 locomotive moves a long train of containers across the country.
- Stone trains, where a Class 59 or Class 70 locomotive moves a very heavy train of aggregate across the country.
- Empty stock movements, where a diesel locomotive moves an electrical multiple unit.
- Supporting Network Rail with trains like the New Measurement Train, which is hauled by two diesel Class 43 power cars.
- Passenger trains at up to and over 100 mph.
I can see a need for several types of zero-carbon locomotive.
- A light freight locomotive.
- A medium freight locomotive, that is capable of hauling many intermodal trains across the country and would also be capable of hauling passenger services.
- A heavy freight locomotive, capable of hauling the heaviest freight trains.
- A Class 43 power car replacement, which would probably be a conversion of the existing power cars. Everybody loves InterCity 125s and there are over a hundred power cars in regular service on railways in the UK.
There are probably others.
The UK Hydrogen Network Is Growing
Regularly, there are news items about companies in the UK, who will be providing green hydrogen to fuel cars, vans, buses, trucks and trains.
Hydrogen is becoming a fuel with a much higher availability.
The UK Electricity Network Is Growing And Getting More Resilient
We are seeing more wind and solar farms and energy storage being added to the UK electricity network.
The ability to support large numbers of battery-electric buses, cars, trucks and trains in a reliable manner, is getting more resilient and much more comprehensive.
There Will Be More Railway Electrification
This will happen and installation will be more innovative. But predicting where electrification will be installed, will be very difficult.
Hydrogen Fuel Cells Now Have Rivals
Hydrogen fuel cells are normally used to convert hydrogen gas to electricity.
But over the last few years, alternative technology has evolved, which may offer better methods of generating electricity from hydrogen.
- Rolls Royce have developed a beer keg-sized 2.5 MW generator, that could run on hydrogen, which I wrote about in Our Sustainability Journey.
- Honeywell are possibly going the same route, which I wrote about in Honeywell Introduces Power Source For Hybrid-Electric Aircraft.
- JCB have converted diesel engines to run on hydrogen, which I wrote about in JCB Finds Cheap Way To Run Digger Using Hydrogen.
- Caterpiller, Cummins and Rolls-Royce mtu are showing signs of taking a similar route to JCB.
Fuel cells will not be having it all their own way.
Batteries Are Improving Their Energy Density
This is inevitable. and you are starting to see improvements in the fabrication of the battery packs to get more kWh into the space available.
In Wrightbus Presents Their First Battery-Electric Bus, I said this about the Forsee batteries used in the new buses from Wrightbus.
The Forsee brochure for the ZEN SLIM batteries gives an energy density of 166 Wh per Kg. This means that the weight of the 454 kWh battery is around 3.7 tonnes.
A one-tonne battery would have a capacity of 166 kWh.
- It is the highest value I’ve so far found.
- Technology is likely to improve.
- Other battery manufacturers will be striving to match it.
For these reasons, in the rest of this post, I will use this figure.
Some Example Locomotives
In this section, I shall look at some possible locomotives.
Conversion Of A Class 43 Power Car
There are two Class 43 power cars in each InterCity 125 train.
- The diesel engine is rated at 1678 kW.
- The transmission is fully electric.
- These days, they generally don’t haul more than five or six intermediate Mark 3 coaches.
I would see that the biggest problem in converting to battery power being providing the means to charge the batteries.
I suspect that these power cars would be converted to hydrogen, if they are converted to zero-carbon.
- I would estimate that there is space for hydrogen tanks and a small gas-turbine generator in the back of the power car.
- Much of the existing transmission could be retained.
- A zero-carbon power car would certainly fit their main use in Scotland and the South-West of England.
- I doubt hydrogen refuelling would be a problem.
They may even attract other operators to use the locomotives.
A Battery-Electric Locomotive Based on A Stadler Class 88 Locomotive
I am using this Class 88 locomotive as a starting point, as the locomotive is powerful, reliable and was built specifically for UK railways. There are also ten already in service in the UK.
In Thoughts On A Battery Electric Class 88 Locomotive On TransPennine Routes, I started the article like this.
In Issue 864 of Rail Magazine, there is an article, which is entitled Johnson Targets A Bi-Mode Future.
As someone, who has examined the mathematics of battery-powered trains for several years, I wonder if the Age of the Hybrid Battery/Electric Locomotive is closer than we think.
A Battery/Electric Class 88 Locomotive
After reading Dual Mode Delight (RM Issue 863), it would appear that a Class 88 locomotive is a powerful and reliable locomotive.
-
- It is a Bo-Bo locomotive with a weight of 86.1 tonnes and an axle load of 21.5 tonnes.
- It has a rating on electricity of 4,000 kW.
- It is a genuine 100 mph locomotive when working from 25 KVAC overhead electrification.
- The locomotive has regenerative braking, when working using electrification.
- It would appear the weight of the diesel engine is around seven tonnes
- The closely-related Class 68 locomotive has a 5,600 litre fuel tank and full of diesel would weight nearly five tonnes.
The locomotive would appear to be carrying between 7 and 12 tonnes of diesel-related gubbins.
Suppose that the diesel-related gubbins of the Class 88 locomotive were to be replaced with a ten tonne battery.
Using the Forsee figures, that I quoted earlier, this battery would hold 1660 kWh.
At the power level of the 700 kW of the Caterpillar C27 diesel engine in the Class 88 locomotive, that would give more than two hours power.
It looks to me, that a battery-electric Class 88 locomotive could be a very useful locomotive.
It might even be able to haul freight trains in and out of the Port of Felixstowe, which would be a big advantage in decarbonising the port.
Certainly, methods to charge battery trains on the move, are being developed like the system from Hitachi ABB Power Grids, that put up short sections of 25 KVAC overhead electrification, which would be driven by a containerised power system.
These systems and others like them, may enable some battery-electric freight trains to work routes like.
- Felixstowe and Ipswich.
- Ipswich and Peterborough
- Peterborough and Nuneaton.
- Peterborough and Doncaster via Lincoln
- Birmingham and Oxford
None of these routes are fully-electrified.
But because of the power limit imposed by the batteries, these locomotives will need to be recharged at points on the route.
This Google Map shows the Ipswich and Peterborough route crossing the Fen Line at Ely station.
Note.
- Ely Dock junction in the South-West corner, where the line from Ipswich and Bury St. Edmunds joins the lines through Ely.
- Ely station towards the North-East corner of the map.
- Passenger trains run through the station.
But freight trains can take a route on the Eastern side of the station, which is not electrified.
At Ely station, a loop like this can be electrified using the existing electrification power supply, but at other places, systems like that from Hitachi ABB Power Grids can be used to electrify the loop or an appropriate section of the route.
These short sections of electrification will allow the train to progress on either electric or battery power.
A Hydrogen-Electric Locomotive Based on A Stadler Class 88 Locomotive
In The Mathematics Of A Hydrogen-Powered Freight Locomotive, I looked at creating a hydrogen-powered locomotive from a Class 68 locomotive.
I decided it was totally feasible to use readily available technology from companies like Rolls-Royce and Cummins to create a powerful hydrogen-powered locomotive.
The Class 68 locomotive is the diesel-only cousin of the electro-diesel Class 88 locomotive and they share a lot of components including the body-shell, the bogies and the traction system.
I suspect Stadler could create a Class 88 locomotive with these characteristics.
- 4 MW using electric power
- At least 2.5 MW using hydrogen power.
- Hydrogen power could come from Rolls-Royce’s 2.5 MW generator based on a small gas-turbine engine.
- 100 mph on both electricity and hydrogen.
- It would have power output on hydrogen roughly equal to a Class 66 locomotive on diesel.
- It would have a range comparable to a Class 68 locomotive on diesel.
This locomotive would be a zero-carbon Class 66 locomotive replacement for all duties.
A Larger And More Powerful Hydrogen-Electric Locomotive
I feel that for the largest intermodal and stone trains, that a larger hydrogen-electric locomotive will be needed.
With the way Wabtec are going in the United States, I wouldn’t be surprised to see a suitable locomotive cross the pond.
Conclusion
In the title of this post, I asked if freight locomotives of the future would be battery, electric or hydrogen.
I am sure of one thing, which is that all freight locomotives must be able to use electrification and if possible, that means both 25 KVAC overhead and 750 VDC third rail. Electrification will only increase in the future, making it necessary for most if not all locomotives in the future to be able to use it.
I feel there will be both battery-electric and hydrogen-electric locomotives, with the battery-electric locomotives towards the less powerful end.
Hydrogen-electric will certainly dominate at the heavy end.
Was This The Most Significant Statement On Freight Locomotives Last Week?
This press release from Freightliner, is entitled Freightliner Secures Government Funding For Dual-Fuel Project.
The dual-fuel project is important and will cut carbon emissions in the short term.
But it is only a quick fix, made possible by good technology.
It is also not zero-carbon.
This sixth paragraph from the press release is very significant.
This sustainable solution will support a programme to decarbonise freight operating companies’ diesel fleets in a cost-efficient manner that does not require significant short-term investment and facilitates operational learning in support of a longer-term fleet replacement programme, potentially using 100% hydrogen fuel.
I believe the paragraph indicates, that Freightliner and possibly the other companies involved in the building and operation of heavy freight locomotives have concluded, that the technology is now such, that a zero-carbon rail locomotive powered by 100 % hydrogen is now possible.
- Rolls-Royce and possibly other gas-turbine companies have the technology to build small gas-turbine powered generators that can produce several megawatts of reliable electrical zero-carbon power, when fuelled by hydrogen.
- We are seeing companies developing strategies for the safe supply of hydrogen in large industrial quantities.
- Hydrogen has been successfully deployed on buses, trains and other large vehicles.
- The technology has been proven that will allow dual-mode hydrogen-electric locomotives, that can use electrification, where it exists.
- Some big companies like Cummins, JCB and Shell are backing hydrogen.
There are thousands of large diesel-powered locomotives all over the world and locomotive builders that can successfully replace these with hydrogen-powered locomotives will not go financially unrewarded!
The Mathematics Of A Hydrogen-Powered Freight Locomotive
If we are going to decarbonise the railways in the UK and in many countries of the world, there is a need to replace diesel locomotives with a zero-carbon alternative.
In looking at Airbus’s proposal for hydrogen powered aircraft in ZEROe – Towards The World’s First Zero-Emission Commercial Aircraft, it opened my eyes to the possibilities of powering freight locomotives using gas-turbine engines running on liquid hydrogen.
A Hydrogen-Powered Equivalent Of A Class 68 Locomotive
The Class 68 Locomotive is a modern diesel locomotive used on UK railways.
This is a brief specification
- It can pull both passenger and freight trains.
- It has an operating speed of 100 mph.
- The diesel engine is rated at 2.8 MW
- It has an electric transmission.
- It has a 5,000 litre diesel tank.
- It weighs 85 tonnes.
- It is 20.5 metres long.
There are thirty-four of these locomotives in service, where some haul passenger trains for Chiltern Railways and TransPennine Express.
Rolls-Royce’s Staggering Development
Staggering is not my word, but that of Paul Stein, who is Rolls-Royce’s Chief Technology Officer.
He used the word in a press release, which I discuss in Our Sustainability Journey.
To electrify aviation, Rolls-Royce has developed a 2.5 MW generator, based on a small gas-turbine engine, which Paul Stein describes like this.
Amongst the many great achievements from E-Fan X has been the generator – about the same size as a beer keg – but producing a staggering 2.5 MW. That’s enough power to supply 2,500 homes and fully represents the pioneering spirit on this project.
This generator is designed for flight and the data sheet for the gas-turbine engine is available on the Internet.
- It has a weight of under a couple of tonnes compared to the thirteen tonnes of the diesel engine and generator in a Class 68 locomotive.
- It is almost as powerful as the diesel.
- It looks to be as frugal, if not more so!
- Rolls-Royce haven’t said if this gas-turbine can run on aviation biofuel, but as many of Rolls-Royce’s large engines can, I would be very surprised if it couldn’t!
Rolls-Royce’s German subsidiary; MTU is a large producer of rail and maritime diesel engines, so the company has the expertise to customise the generator for rail applications.
Could this generator be modified to run on liquid hydrogen and used to power a Class 68-sized locomotive?
- The size of the generator must be an advantage.
- Most gas-turbine engines can be modified to run on natural gas and hydrogen.
- Its power output is electricity.
- There’s probably space to fit two engines in a Class 68 locomotive.
In addition, a battery could be added to the transmission to enable regenerative braking to battery, which would increase the efficiency of the locomotive.
Storing Enough Hydrogen
I believe that the hydrogen-powered locomotive should carry as much energy as a Class 68 locomotive.
- A Class 68 locomotive has a capacity of 5,000 litres of diesel fuel.
- This will have a mass of 4.19 tonnes.
- Each kilogram of diesel can produce 47 Mega Joules of energy.
- This means that full fuel tanks contain 196,695 Mega Joules of energy.
- Each litre of liquid hydrogen can produce 10.273 Mega Joules of energy
This means that to carry the same amount of energy will need 19,147 litres or 19.15 cubic metres of liquid hydrogen.
- This could be contained in a cylindrical tank with a diameter of 2 metres and a length of 6 metres.
- It would also weigh 1.38 tonnes.
The E-Fan-X aircraft project must have worked out how to store, similar amounts of liquid hydrogen.
Note that I used this Energy And Fuel Data Sheet from Birmingham University.
Running On Electrification
As the locomotive would have an electric transmission, there is no reason, why it could not run using both 25 KVAC overhead and 750 VDC third-rail electrification.
This would enable the locomotive to haul trains efficiently on partially electrified routes like between Felixstowe and Leeds.
Hydrogen-Powered Reciprocating Engines
When it comes to diesel engines to power railway locomotives and big trucks, there are few companies bigger than Cummins, which in 2018, turned over nearly 24 billion dollars.
- A large proportion of this revenue could be at risk, if governments around the world, get serious about decarbonisation.
- Cummins have not let the worst just happen and in 2019, they acquired Hydrogenics, who are a hydrogen power company, that they now own in an 81/19 partnership with Air Liquide.
- Could all this expertise and Cummins research combine to produce powerful hydrogen-powered reciprocating engines?
- Other companies, like ABC and ULEMCo are going this route, to modify existing diesel engines to run on hydrogen or a mixture of hydrogen and diesel.
I believe it is very likely, that Cummins or another company comes up with a solution to decarbonise rail locomotives, based on a conversion of an existing diesel engine.
Refuelling Hydrogen-Powered Rail Locomotives
One of problems with hydrogen-powered trucks and cars, is that there is no nationwide refuelling network providing hydrogen. But railway locomotives and trains usually return to depots at the end of the day for servicing and can be fuelled there.
Conclusion
I feel that there are several routes to a hydrogen-powered railway locomotive and all the components could be fitted into the body of a diesel locomotive the size of a Class 68 locomotive.
Consider.
- Decarbonising railway locomotives and ships could be a large market.
- It offers the opportunities of substantial carbon reductions.
- The small size of the Rolls-Royce 2.5 MW generator must offer advantages.
- Some current diesel-electric locomotives might be convertible to hydrogen power.
I very much feel that companies like Rolls-Royce and Cummins (and Caterpillar!), will move in and attempt to claim this lucrative worldwide market.
Environmentally-Friendly InterCity 125 Trains
InterCity 125 trains are not the most environmentally-friendly of beasts.
- They do not meet the modern emission regulations.
- They still emit a lot of carbon dioxide.
- They is also a deadline of 2040, when UK railways will be net-carbon-free.
There might also be individuals and groups, who feel that these elderly trains with so much history, should be replaced by modern zero-carbon trains.
- Would the same groups accept electrification with all the wires?
- Would the train operating companies, accept battery power with long waits for charging?
- Would hydrogen be viable on the numerous branch lines in Devon and Cornwall, with some difficult access to depots by road. Especially, if the hydrogen had to be brought from say Bristol or Southampton!
But various engineering solutions are emerging.
Biodiesel
This is probably the simplest solution and I suspect most modern engines can run on biodiesel with simple modifications. InterCity 125s have modern engines from German firm and Rolls-Royce subsidiary; MTU, so they probably have a solution in their tool-box.
Computerisation
I have never built a computer control system for anything, but I did work with the first engineers in the world, who computerised a chemical plant.
They always emphasised, if you could nudge the plant into the best area of operation, you’d have a much more efficient plant, that produced more product from the same amount of feedstock.
At about the same time, aircraft engine manufacturers were developing FADEC or Full Authority Digital Engine Control, which effectively let the engine’s control system take over the engine and do what the pilot had requested. The pilot can take back control, but if FADEC fails, the engine is dead.
But judging by the numbers of jet aircraft, that have engine failures, this scenario can’t be very common, as otherwise the tabloids would be screaming as they did recently over the 737 MAX.
Now, I don’t know whether the MTU 16V4000 R41R engines fitted to the InterCity 125, have an intelligent FADEC to improve their performance or whether they are of an older design.
If you worry about FADEC, when you fly, then read or note these points.
- Read the FADEC’s Wikipedia entry.
- Your car is likely to be heavily computerised.
- If you took a modern train or bus to the airport, that certainly will have been heavily computerised.
You could be more likely to meet someone with COVID-19 on a flight, than suffer an air-crash, depending on where you travel.
Rolls-Royce’s Staggering Development
Staggering is not my word, but that of Paul Stein, who is Rolls-Royce’s Chief Technology Officer.
He used the word in a press release, which I discuss in Our Sustainability Journey.
To electrify aviation, Rolls-Royce has developed a 2.5 MW generator, based on a small gas-turbine engine, which Paul Stein describes like this.
Amongst the many great achievements from E-Fan X has been the generator – about the same size as a beer keg – but producing a staggering 2.5 MW. That’s enough power to supply 2,500 homes and fully represents the pioneering spirit on this project.
This generator is designed for flight and the data sheet for the gas-turbine engine is available on the Internet.
- It has a weight of under a couple of tonnes compared to the thirteen tonnes of the diesel engine and generator in a Class 68 locomotive.
- It is also more powerful than the diesel.
- It looks to be as frugal, if not more so!
- Rolls-Royce haven’t said if this gas-turbine can run on aviation biofuel, but as many of Rolls-Royce’s large engines can, I would be very surprised if it couldn’t!
Rolls-Royce’s German subsidiary is a large producer of rail and maritime diesel engines, so the company has the expertise to customise the generator for rail applications.
Conclusion
I think it is possible, that the Class 43 power-cars can be re-engined to make them carbon-neutral.
ZEROe – Towards The World’s First Zero-Emission Commercial Aircraft
The title of this post, is the same as that of this Press Release from Airbus.
This is the introductory paragraph.
At Airbus, we have the ambition to develop the world’s first zero-emission commercial aircraft by 2035. Hydrogen propulsion will help us to deliver on this ambition. Our ZEROe concept aircraft enable us to explore a variety of configurations and hydrogen technologies that will shape the development of our future zero-emission aircraft.
Overall, the Press Release discloses a lot and gives details of three different aircraft, which are shown in this Airbus infographic.
Discover the three zero-emission concept aircraft known as ZEROe in this infographic. These turbofan, turboprop, and blended-wing-body configurations are all hydrogen hybrid aircraft.
I have some thoughts that apply to all three concepts.
Hydrogen Hybrid Power
The Press Release says this about the propulsion systems for the three aircraft.
All three ZEROe concepts are hydrogen hybrid aircraft. They are powered by hydrogen combustion through modified gas-turbine engines. Liquid hydrogen is used as fuel for combustion with oxygen.
In addition, hydrogen fuel cells create electrical power that complements the gas turbine, resulting in a highly efficient hybrid-electric propulsion system. All of these technologies are complementary, and the benefits are additive.
There is a Wikipedia entry which is entitled Hydrogen Fuel, where this is said.
Once produced, hydrogen can be used in much the same way as natural gas – it can be delivered to fuel cells to generate electricity and heat, used in a combined cycle gas turbine to produce larger quantities of centrally produced electricity or burned to run a combustion engine; all methods producing no carbon or methane emissions.
It looks like the aircraft will be powered by engines that are not too different to the current engines in today’s aircraft.
This must be a big advantage, in that much of the research done to improve the current gas-turbine powered by aviation fuel will apply.
Liquid Hydrogen
It appears all three aircraft will use liquid hydrogen.
Liquid Hydrogen Storage
I believe the major uses for hydrogen will be aircraft, buses, cars, rail locomotives and multiple units and heavy trucks.
All will need efficient storage of the hydrogen.
Some applications, will use it in liquid form, as it is a more dense form, but it will need to be kept cold.
As aviation will probably be the most demanding application, will it drive the storage technology?
Oxygen
This will be atmospheric oxygen, which is used by any combustion engine.
Fuel Cells
Will the fuel cells be used to provide power for the plane’s systems, rather than to power the aircraft?
Most airlines do this with an auxiliary power unit or APU, which is just a small gas-turbine engine with a generator. The A 320 family use one made by Pratt & Whitney, which is described on this page of their web site. It is the third one on the page and is called a APS3200. This is said about its function.
Pratt & Whitney APS3200 is the Airbus baseline APU of choice for the Airbus A320 family of aircraft. It is designed to meet performance and environmental requirements for modern day, single-aisle aircraft. The APU comprises a single-shaft, fixedspeed, high-pressure ratio core driving a load compressor that provides bleed air for cabin conditioning and main engine starting, concurrent with 90kVA of electrical power.
The APU is usually located in the tail.
In the ZEROe family will there be a fuel-cell powered compressor to provide bleed air for cabin airconditioning and main engine starting?
Slippery Aerodynamics
Airbus seem to be the masters of slippery aerodynamics, which will help make the planes very fuel efficient.
Lightweight Composite Structures
Like the latest Airbus airliners, these planes will be made from lightweight composite structures and I wouldn’t be surprised to see weight saving in other parts of the aircraft.
Carbon Emissions And Pollution
There will be no carbon dioxide produced, as where’s the carbon in the fuel?
But there could be small amounts of the oxides of nitrogen produced, by the combustion, as nitrogen will be present from the air.
Noise
As the aircraft are powered by gas-turbine engines, there will be some noise.
The Mathematics Of Hydrogen-Powered Aviation
The mathematics for these three aircraft must say, that the designs are feasible.
Otherwise Airbus wouldn’t have published a detailed Press Release, only for it to be torn to pieces.
Pressures Driving Aviation In The Next Ten Years
Aviation will change in the text ten years and it will be driven by various competing forces.
Environmental Issues
Pollution, Carbon Emissions and Noise will be the big environmental issues.
Hydrogen will go a long way to reducing the first two issues, but progress with noise will generally be made by better engineering.
COVID-19 And Future Pandemics
These could have a bigger effect, as to make flying safe in these troubled times, passengers will need to be given more space.
But I do wonder, if there is an administrative solution, backed up, by innovative engineering.
Could a very quick test for COVID-19, that would stop infected passengers boarding, coupled with high quality automatic cleaning and air purification, ensure that passengers didn’t get infected?
Entry Into Service
Airbus are quoting 2035 in the Press Release and this YouTube video.
Is that ambitious?
Thoughts On The Three Designs
My thoughts on the three designs, follow in the next three sections.
The ZEROe Turboprop
This is Airbus’s summary of the design for the ZEROe Turboprop.
Two hybrid hydrogen turboprop engines, which drive the six bladed propellers, provide thrust. The liquid hydrogen storage and distribution system is located behind the rear pressure bulkhead.
This screen capture taken from the video, shows the plane.
It certainly is a layout that has been used successfully, by many conventionally-powered aircraft in the past. The De Havilland Canada Dash 8 and ATR 72 are still in production.
The Turboprop Engines
If you look at the Lockheed-Martin C 130J Super Hercules, you will see it is powered by four Rolls-Royce AE 2100D3 turboprop engines, that drive 6-bladed Dowty R391 composite constant-speed fully-feathering reversible-pitch propellers.
These Rolls-Royce engines are a development of an Allison design, but they also form the heart of Rolls-Royce’s 2.5 MW Generator, that I wrote about in Our Sustainability Journey. The generator was developed for use in Airbus’s electric flight research program.
I wouldn’t be surprised to find the following.
- , The propulsion system for this aircraft is under test with hydrogen at Derby and Toulouse.
- Dowty are testing propellers suitable for the aircraft.
- Serious research is ongoing to store enough liquid hydrogen in a small tank that fits the design.
Why develop something new, when Rolls-Royce, Dowty and Lockheed have done all the basic design and testing?
The Fuselage
This screen capture taken from the video, shows the front view of the plane.
From clues in the picture, I estimate that the fuselage diameter is around four metres. Which is not surprising, as the Airbus A320 has a height of 4.14 metres and a with of 3.95 metres.
So is the ZEROe Turboprop based on a shortened Airbus A 320 fuselage?
As the aircraft has a capacity of less than a hundred passengers and an Airbus A320 has six-abreast seating, could the aircraft have sixteen rows of seats.
With the seat pitch of an Airbus A 320, which is 81 centimetres, this means just under thirteen metres for the passengers.
The Technical Challenge
I don’t feel there are any great technical challenges in building this aircraft.
- The engines appear to be conventional and could even have been more-or-less fully developed.
- The fuselage could be a development of an existing design.
- The wings and tail-plane are not large and given the company’s experience with large composite structures, they shouldn’t be too challenging.
- The hydrogen storage and distributing system will have to be designed, but as hydrogen is being used in increasing numbers of applications, I doubt the expertise will be difficult to find.
- The avionics and other important systems could probably be borrowed from other Airbus products.
Given that the much larger and more complicated Airbus A380 was launched in 2000 and first flew in 2005, I think that a prototype of this aircraft could fly around the middle of this decade.
The Market Segment
It may seem small at less than a hundred seats, but it does have a range of greater than a 1000 nautical miles or 1150 miles.
Consider.
- It compares closely in passenger capacity, speed and range, with the De Havilland Canada Dash 8/400 and the ATR 72/600.
- The ATR 72 is part produced by Airbus.
- The aircraft is forty percent slower than an Airbus A 320.
- It is a genuine zero-carbon aircraft.
- It looks like it could be designed to have a Short-Takeoff-And Landing (STOL) capability.
On the other hand, a lot of busy routes, like London and Edinburgh and Berlin and Munich are less than or around 400 miles.
These short routes are being challenged aggressively by the rail industry, as over this sort of distance, which typically takes four hours by train, rail has enough advantages, that passengers may choose not to fly.
Examples of cities with a range of between 400 and 1000 miles from London include.
- Berlin – 571 miles
- Cork – 354 miles
- Inverness – 445 miles
- Lisbon – 991 miles
- Madrid – 781 miles
- Palma – 835 miles
- Rome – 893 miles
- Stockholm – 892 miles
- Warsaw – 900 miles
This aircraft would appear to be sized as an aircraft, that can fly further than passengers are happy to travel by train. But because of its cruising speed, the routes, where it will be viable would probably be limited in duration.
But important routes to, from and between secondary locations, like those that used to be flown by FlyBe, would surely be naturals for this aircraft.
It looks to be an aircraft that could have a big future.
The ZEROe Turbofan
This is Airbus’s summary of the design.
Two hybrid hydrogen turbofan engines provide thrust. The liquid hydrogen storage and distribution system is located behind the rear pressure bulkhead.
This screen capture taken from the video, shows the plane.
This screen capture taken from the video, shows the front view of the plane.
The aircraft doesn’t look very different different to an Airbus A320 and appears to be fairly conventional. It does appear to have the characteristic tall winglets of the A 320 neo.
The Turbofan Engines
These would be standard turbofan engines modified to run on hydrogen, fuelled from a liquid hydrogen tank behind the rear pressure bulkhead of the fuselage.
If you want to learn more about gas turbine engines and hydrogen, read this article on the General Electric web site, which is entitled The Hydrogen Generation: These Gas Turbines Can Run On The Most Abundant Element In the Universe,
Range And Performance
I will compare range, performance and capacity with the latest Airbus A 320.
ZEROe Turbofan
- Range – 2300 miles
- Cruising Speed – Mach 0.78
- Capacity – < 200 passengers
Airbus A 320
- Range – 3800 miles
- Cruising Speed – Mach 0.82
- Capacity – 190 passengers
There is not too much difference, except that the A 320 has a longer range.
The Cockpits Of The ZEROe Turboprop And The ZEROe Turbofan
This gallery puts the two cockpit images together.
Are they by any chance related?
Could the controls and avionics in both aircraft be the same?
A quick look says that like the Boeing 757 and 767, the two planes have a lot in common, which may enable a pilot trained on one aircraft to fly the other, with only minimal extra instruction.
And would it be a simple process to upgrade a pilot from an A 320 to a ZEROe Turbofan?
The Fuselages Of The ZEROe Turboprop And The ZEROe Turbofan
I estimated earlier that the fuselage of the Turboprop was based on the cross-section of the A320.
Looking at the pair of front views, I wouldn’t be surprised to find, that both aircraft are based on an updated A 320 fuselage design.
Passengers and flightcrew would certainly feel at home in the ZEROe Turbofan, if internally, it was the same size, layout and equipment as a standard A 320 or more likely an A 320 neo.
The Market Segment
These are my thoughts of the marketing objectives of the ZEROe Turbofan.
- The cruising speed and the number of passengers are surprisingly close, so has this aircraft been designed as an A 320 or Boeing 737 replacement?
- I suspect too, that it has been designed to be used at any airport, that could handle an Airbus A 320 or Boeing 737.
- It would be able to fly point-to-point flights between most pairs of European or North American cities.
It would certainly fit the zero-carbon shorter range airliner market!
In fact it would more than fit the market, it would define it!
The ZEROe Blended-Wing Body
This is Airbus’s summary of the design.
The exceptionally wide interior opens up multiple options for hydrogen storage and distribution. Here, the liquid hydrogen storage tanks are stored underneath the wings. Two hybrid hydrogen turbofan engines provide thrust.
This screen capture taken from the video, shows the plane.
This aircraft is proposed to have the same performance and capacity as the ZEROe Turbofan, which includes a 2000 nautical mile plus range.
The only other aircraft with a similar shape is the Northrop Grumman B-2 Spirit or Stealth Bomber. This is not a fast aircraft, but it is able to fly at an altitude of 50,000 ft, which compares to the 60,000 ft of Concorde and the 43,000 ft of an Airbus A 380.
I wonder, if the blended-wing body is designed to fly very high at around the 60,000 ft, which was Concorde territory.
It would only be doing 515 mph and would be well below the speed of sound.
So what is the point on going so high?
The air is very thin and there is a lot less drag.
It is also worth reading Wikipedia on the design of flying wings.
It might be possible to fly much further than 2000 nautical miles. After all Airbus did put in a plus sign!
Is this aircraft the long-distance aircraft of the three?
Extending The Range
I do wonder, if the engines in these aircraft could be capable of running on both hydrogen and aviation biofuel.
As the ZEROe Turboprop and the ZEROe Turbofan planes have empty wings, which in a conventional aircraft would hold fuel, could the space be used to hold aviation biofuel to extend the range?
Certification Of The Planes
The ZEROe Turboprop and ZEROe Turbofan are aircraft, where a lot of the design will already have been proven in previous aircraft, so will probably be much less onerous to approve, than the blended-wing body design.
Conclusion
It looks to me, that Airbus have designed three aircraft to cover the airline market.
I also feel that as the ZEROe Turboprop and ZEROe Turbofan, appear to have conventional airframes, that they could be delivered before 2035.
If I’m right, that the blended-wing body is a high flyer, it will be a ride to experience, travelling at that height all the way to New York.
The Anonymous Widower 