Tag Archive for: hydrogen propulsion

Green hydrogen ‘comes back to the future’

Green hydrogen as a source of fuel can be essential for decarbonizing the transport sector, especially for covering the limitations of electric solutions and other clean energies, since it is found easily and thanks to the increase of research projects worldwide, green H is getting cheaper.

Anthony-Rampersad_Unsplash_Green Hydrogen

What is ‘Green Hydrogen’?

Green Hydrogen is a source of energy that has no colour, no odour or taste, is abundant and it does not emit any carbon dioxide emissions when used to power fuel cells.

There are different types of hydrogen and every type has its characteristics; they’re essentially colour codes, used within the energy industry to mark each type of hydrogen.It can be grey, blue, green, brown and even yellow and pink, depending on the type of products used, different colours are assigned to the hydrogen.

As the iconic movie trilogy of the mid-’80s “Back to the future” predicted, we can say that hydrogen “comes back to the future”.

Many factors make this raw material so appealing as a great alternative in comparison to electric and carbon fuels. And especially, now is the time to incentivise green fuels as the need for decarbonising the planet is one of the goals that countries around the world have set for 2050, especially the European Union.

How does Green Hydrogen work?

As explained before, hydrogen has no colour, but the name of the colour is given by the type of waste in the production process. Grey and blue come from fossil fuels that generate CO2, and the resulting emissions are captured, stored and not released into the atmosphere. Pink hydrogen comes through electrolysis powered by nuclear energy, yellow is a relatively new phrase for hydrogen made through electrolysis using solar power. Brown hydrogen is made using black coal or lignite (brown coal), these black and brown hydrogen are the opposite of green hydrogen in the hydrogen spectrum and the most environmentally damaging – whereas green hydrogen does not generate any emission neither in the production process nor the combustion.

Green Hydrogen is produced with no harmful greenhouse gas emissions and is generated by using clean electricity from surplus renewable energy sources, such as solar or wind power, to electrolyse water. Electrolysers use an electrochemical reaction to split water into its components of hydrogen and oxygen, emitting zero-carbon dioxide in the process, according to National Grid information.

How can the transport sector make use of green hydrogen?

Since the transport sector represents the source of one-third of total CO2 emissions in Europe, it could benefit from the renewed attention on hydrogen to replace fossil fuels and meet the European Union decarbonisation goals. This way it could be a lead actor in the transport sector where batteries are an impracticable solution to substitute fossil fuels powering ferries, coasting trade or inland waterways and in rail applications.

Currently, the production of green hydrogen represents a small percentage of the overall, this is due to the elevated costs of production. Green hydrogen will come down in price as it becomes more common, providing an answer to one of the great challenges facing the energy sector. Developing systems to store surplus energy from renewables on a large scale, reduce Europe’s energy dependence, and cover gap areas since electric energy cannot be used in all transport systems as in maritime transport.

What are the obstacles to using green hydrogen?

So, can green hydrogen be implemented right away in the transportation sector? One of the biggest barriers to the adoption of this fuel for the transport sector comes from the low supply, since FC vehicles are expensive, although mass-production could reduce costs, as well as the difficulties of mass market diffusion in hydrogen storage. If applied in the current scenario of mass production vehicles for transport and fuels, hydrogen could reach areas where batteries and electric energy sources cannot cover.

Application in maritime transport

One of the major consumers of oil products and heavy fuels is the maritime sector, harming the quality of air, especially around ports. If applied to the engines of the maritime transport sector, green hydrogen could reduce not only emissions during sea navigation, but also those deriving from port operations.

In the last year, there have been some steps towards creating the world’s first hydrogen-powered cargo ship. Implementing this technology on ships, ferries and other coastal crafts could strongly reduce CO2 emissions.

Application in rail transport

Currently, it is difficult to electrify certain sections of railway lines on which fossil fuel-powered trains are used. Hydrogen trains are considered competitive for those railway sections that don’t depend on electric energy, with a low frequency of service and operate on long distances. These conditions are frequent in rail transport, making hydrogen rail mobility interesting from an economic point of view and an excellent opportunity to further decarbonise public transport, according to Enea, (Agenzia nazionale per le nuove tecnologie, l’energia e lo sviluppo economico sostenibile).


Certainly, we will see green hydrogen powering sectors that strongly depend on carbon fuels as companies and countries meet the goals for reducing carbon dioxide emissions, especially in the maritime and rail transport sectors. This is without a doubt a comeback to clean and essential sources of energy and as the famous DeLorean from the film, engines will be using clean hydrogen to keep up the pace.



The hydrogen colour spectrum | National Grid Group

 Hydrogen and “green transport” – EAI (enea.it)

Green Hydrogen: an essential element for decarbonization (cepsa.com)

Alternative Fuels Data Center: Hydrogen Benefits and Considerations (energy.gov)


From LNG to Hydrogen? Pitfalls and Possibilities

Liquid hydrogen could get a leg up from the industry’s experience with LNG propulsion,writes Stevie Knight.

Gerd-Michael Wuersig, DNV-GL’s business director for Alternative Fuels explains: “While hydrogen doesn’t come under the IGF code as yet, from my point of view I’d say the maritime industry’s hesitancy is more due to missing experience; most of the process technology and safety principles that relate to LNG will relate to hydrogen, and while there are different factors involved, in the end the risk level will not be very different. This is the good news.”

The bad news is that while your shipboard or bunkering design might look very similar, the components, like valves, hoses and piping are not necessarily interchangeable: “It’s a smaller molecule and it can escape through joints or seals that would retain LNG,” he adds. “You’d have to look to see if the current components would be suitable – but most likely I think you’ll have changes in your equipment,” says Dr Wuersig. And, he adds, it’ll work out quite a bit more pricey.

However, he also points out that the while it may be a novel application, the technology itself is not new.Joe Pratt underlines this point: “The equipment and expertise has been in existence for a long time. In North America, for example, LH2 production, handling, and distribution have been mature for over 50 years… So a lot of the components will come off the shelf.”

More, LNG developments can’t help much here as at this point the design deviates sharply. Two characteristics of LH2 are low density and low boiling temperature: together these demand an extremely low heat flux through the tank walls.

Dr Wuersig explains that the normal 40cm LNG insulation “just won’t work”. He says a moderately large LNG tank could lose 0.2% of its total volume a day but “store hydrogen in the same kind of tank and you would actually lose 5% of the contents every day to vaporisation”.

“Therefore to get down to roughly the same boil off rate the insulation of the hydrogen tank must be about 10 times more efficient than an LNG tank,” says Dr Wuersig. “In fact you need a system that is gas tight from the outside as well as the inside with no chance of the air finding its way into the insulation – if it does it will condense, and this will suck yet more air in.”

A multilayer approach with an evacuated space between the inner and outer shell is already being used to keep LH2 and liquid helium cold in the industrial sector, but there’s only one project so far – for a KHI-designed ship – that’s being scaled for the marine trading world, although the eventual development of larger vessels will have an advantage because higher capacity tanks exhibit a lower boil off rate.

There are other dissimilarities between LNG and LH2. Dr Pratt says when it comes to bunkering, “the biggest difference is the much colder temperature of LH2” and explains that unlike LNG, H2 is actually colder than oxygen or nitrogen. While LNG can hover at -163°C, liquid hydrogen needs to be kept at -253°C.

So, “even through vacuum insulation you will get very cold temperature on the outside of the pipe that can freeze or condense oxygen and nitrogen out of the air”.  For practical purposes, not only do you need a very high grade of insulation, “there will be some drip pans and possibly restrictions on fuelling over asphalt to prevent any fire possibility as a result of having pure oxygen forming around the pipes”, said Dr Pratt.


Hydrogen is already the chosen option for a number of smaller vessels with an environmental agenda: “Norway is working on constructing hydrogen fuelled vessels, mostly battery hybrids, as it is aiming for zero emissions in the fjords,” says Dr Wuersig. The autonomous Energy Observer, which electrolyses seawater for fuel, has recently set off on a six year missionand Dr Pratt is himself pursuing the build of a small, multipurpose freight carrier for California through GGZEM.

But, the most obvious question is: would hydrogen be a useful alternative for big ships?

First of all, bigger ships will need to bunker liquefied, not compressed, hydrogen. Dr Pratt says: “In general, it’s always better to go to LH2 if you can get it and afford the cost difference – it gives you more range or longer times between refuelling than gas, no matter what the size of the vessel.” This obviously needs the development of infrastructure – and here again, the industry experience with LNG will be invaluable – but on which kinds of vessels could it find a home?

Sandia’s research Practical Application Limits of Fuel Cells and Batteries for Zero Emission Vessels* (at the time lead by Dr Pratt), has dug deep into the nitty-gritty, with a look at no less than 14 possible ships and their associated routes.

This takes a detailed look not just at the power required, but whether the ship could actually accommodate the necessary architecture – helped of course by the fact that fuel cells, unlike a shaft drive engine, can be positioned in a variety of areas.

One of the 14 studies was the 397m Emma Maersk. Despite the large power and energy requirements, the research showed that the ship is able to hold a fuel cell powerplant using liquid hydrogen, scaled for a single voyage from Tanjung Pelepas, Malaysia to Port Said, Egypt with a total voyage time of 256hr at an average speed of 19.6 knots and average shaft power of 36.1MW. This would require bunkering with 616t of LH2.

Likewise, a detailed look at Colombo Express (335m) showed that it could carry out three of its typical, single trips between Singapore and Colombo, Sri Lanka, fuelled with 183t of LH2.

The devil is in the detail. Dr Wuersig points out that hydrogen has a low energy density by volume (though not by weight) which is only around 40% of that LNG. As already pointed out, LH2 isn’t heavy, but one tonne of it takes up over 14,128 litres by volume: this means 8,500m3 of LH2 for that Emma Maersk journey on LH2.

Could it be done? Yes, but it’s tricky as deep sea routes aren’t made up of single journeys. Taking the kind of operational profile that’s used onboard the latest LNG-fuelled CMA CGM ships which require an 18,000m3 tank installed underneath the wheelhouse, “you’d need 50,000m3 instead” he says. Further, he estimates the Asia-Europe string is 40 days: therefore the Emma Maersk would need around 72,000m3 to transit this on LH2 alone.

However, the case is different for shorter runs: according to the Sandia study, Colombo Express fairs better: 833m3 for that Singapore-Colombo single trip (2,500m3 for three journeys).

More, both agree that when it gets to ropax crossings like those between the east coast of the UK and Rotterdam, there’s obviously an advantage as it’s a short, regular, point-to-point journey “and you do need the infrastructure to deliver the hydrogen, something that’s caused other viable projects to fail” says Dr Pratt. Certainly Sandia’s investigation showed that Pride of Hull has room for a fuel cell and LH2 tank scaled for 15.8t of fuel, yielding no less than five crossings on just one fill up.

Dr Wuersig adds there are many other areas that might see hydrogen as a viable alternative for slightly larger ships on a regular run: “Baltic carriers for example, could benefit because they could be filling up every few days; then there’s the US-Hawaii traffic on the Jones Act ships.” More, he adds that Chinese river traffic is presently looking LNG, but there could soon be a lot of renewable energy capacity in China that might not all be easily absorbed by the grid “which might change the maths when it comes to the generation of sustainable fuels”.

It’s not just China, some of the windfarms and renewable arrays around offshore Europe are presently considering generating hydrogen in their off-peak periods.

More, Sandia’s study on the offshore supply vessel Maersk Frontier showed it could take on no less than 28 single trips (14 round trips) on the 166nm journey between home port in Aberdeen UK and the Janice offshore facility at an average 9.7 knots, so LH2 could be worthwhile for wider ranging applications. Even closer to realisation is Zero-V, a coastal research vessel concept by Glosten, Sandia and the Scripps Institution of Oceanography that’s just been given AIP by DNV GL. Supported by bunkering of its 11,000kg capacity tanks at four ports along the US West Coast, it will have a 10kn range of 2,400 nautical miles.

However, another niggling detail presents itself: LH2 is also expensive to create: “At present production costs alone come to around $2.00 per litre, that’s without the base feed,” says Dr Wuersig. And no, it probably won’t get a lot cheaper – it’s down to the physics. The amount of energy required for liquefying hydrogen takes a huge 30% slice out of the total, compared to about 5% for LNG.

This is one of the main reasons that hydrogen hasn’t already found a niche: however, we’ve not experienced this regulatory landscape before, points out Dr Wuersig. “If we keep to our carbon ambitions, then yes, there will be reason to employ hydrogen as one of a number of multiple fuel options.”

* Practical Application Limits of Fuel Cells and Batteries for Zero Emission Vessels (http://energy.sandia.gov/wp-content/uploads/2017/12/SAND2017-12665.pdf). 


The LH2 demonstrator is not the first long-range hydrogen supply chain project targeting Japan.

Last year, Chiyoda Corp started to work on transporting hydrogen extracted from natural gas at an LNG plant in Brunei and delivering it to the city of Kawasaki in Japan – but rather than chilling to -253°C, the hydrogen is bound to a carrier substance and carried in simple chemical tankers which slot neatly into the existing supply-chain technology. No need for expensive cryogenics.

Transforming hydrogen into an ambient liquid means binding it with a carrier substance, such as toluene, converting it to methyl cyclohexane (MCH) by hydrogenation: three H2 molecules attach to every molecule of toluene. At the other end it’s reconverted to hydrogen gas, the toluene being recovered for the next round.

Professor Kazuyuki Ouchi, University of Tokyo explains that the density, while not quite as high as LH2 (500 times that of hydrogen gas, as compared to 700 times) “it is of the same order” so yields a tolerably similar output.

Interestingly, the project, which is expected to start production in 2020 with an output of 210 tonnes (enough to fill up 40,000 fuel cell vehicles), has Mitsubishi Corporation, NYK and Mitsui onboard.

More, while it’s starting with a fossil fuel base, Chiyoda believes that production will eventually move to renewably-derived hydrogen.

Source: The Motorship

Toyota presents the first vessel propelled by hydrogen

The vessel, which travels around the world, has a reduced weight thanks to its production system, as it does not have to store all the energy in batteries.

Toyota has just presented the first energy-autonomous boat, which runs on hydrogen and does not emit greenhouse gases or particles. The Energy Observer, launched in 2017 in the French town of Saint-Malo, uses a combination of renewable energies and a system that produces hydrogen from seawater without emitting any carbon.

The vessel, which will sail around the world, uses technologies that will serve as the basis for tomorrow’s energy networks. It’s voyage of approximately six years constitutes a challenge from the human and technological point of view that will put the systems used in extreme circumstances to the test.

Hydrogen is the key to the Energy Observer project and the main reason for Toyota’s participation in the project. Thanks to its production system, the weight of the ship has been considerably reduced compared to the alternative of storing all the energy in batteries.

Its use as a means of storage is key to overcoming the problem of intermittent power supply both on land and at sea, because it allows to take advantage of the surplus and extend the autonomy of mobile facilities.

Source: Cadena de Suministro.