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IISA study proposes using airships for efficient cargo or hydrogen transportation

Reintroducing airships into the world’s transportation mix could contribute to lowering the transport sector’s carbon emissions and can play a role in establishing a sustainable hydrogen based economy, according to a new IIASA-led study. The open-access paper is published in the journal Energy Conversion and Management: X.

Airships were introduced in the first half of the 20th century before conventional aircraft were used for the long-range transport of cargo and passengers. Their use in cargo and passenger transport was however quickly discontinued for a number of reasons, including the risk of a hydrogen explosion (for which the Hindenburg disaster of 1937 served as a stark case in point); their lower speed compared to that of airplanes; and the lack of reliable weather forecasts.

Since then, considerable advances in material sciences; the ability to forecast the weather; and the need to reduce energy consumption and CO2 emissions, have steadily been bringing airships back into political, business, and scientific conversations as a possible transportation alternative.

The transport sector is responsible for around 25% of global CO2 emissions caused by humans. Of these emissions, 3% come from cargo ships, but this figure is expected to increase by between 50% and 250% until 2050. These projections necessitate finding new approaches to transporting cargo with a lower demand for energy and lower CO2 emissions.

In the study, researchers from IIASA, Brazil, Germany, and Malaysia looked into how an airship-based industry could be developed using the jet stream as the energy medium to transport cargo around the world.

The jet stream is a core of strong winds that flows from west to east, around 8 to 12 kilometers above the Earth’s surface. According to the researchers, airships flying in the jet stream could reduce CO2 emissions and fuel consumption, as the jet stream itself would contribute most of the energy required to move the airship between destinations, resulting in a round trip of 16 days in the northern hemisphere, and 14 days in the southern hemisphere. This is considerably less time compared to current maritime shipping routes, particularly in the southern hemisphere.

The researchers postulate that the reintroduction of airships into the transport sector could also offer an alternative for the transport of hydrogen. Hydrogen is a good energy carrier and a valuable energy storage alternative. Given that renewable electricity, for example, excess wind power, can be transformed into hydrogen, there is some optimism that the hydrogen economy will form a fundamental part of a clean and sustainable future.

One of the challenges to implementing a hydrogen-based economy is cooling the hydrogen to below -253°C to liquefy it. The process consumes almost 30% of the embodied energy, with further energy of around 3% required to transport the liquefied hydrogen. In their study, the authors however propose that instead of using energy in liquefaction, hydrogen in gaseous form could be carried inside the airship or balloon and transported by the jet stream with a lower fuel requirement. Once the airship or balloon reaches its destination, the cargo can be unloaded removing around 60% or 80% of the hydrogen used for lift, and leaving 40% or 20%, of the hydrogen inside the airship or balloon to provide enough buoyancy for the return trip without cargo.

To address the risk of combustion of the hydrogen in the airship, the authors suggest automating the operation, loading, and unloading of hydrogen airships and designing flightpaths that avoid cities to reduce the risk of fatalities in the event of an accident.

According to study lead-author Julian Hunt, an IIASA post-doctoral fellow, a further interesting aspect unveiled in this study is the possibility that airships and balloons can also be used to improve the efficiency of liquefying hydrogen. As the temperature of the stratosphere (where the airships will be flying to utilize the jet stream) varies between -50°C to -80°C, it means that less energy will be required to meet the -253°C mark if the process happens onboard the airship. The energy required for the additional cooling needed can be generated using the hydrogen in the airship.

Hunt says that this process also presents a number of additional possibilities: The process of generating energy from hydrogen produces water—one ton of hydrogen produces nine tons of water. This water could be used to increase the weight of the airship and further save energy in its descending trajectory.

Another possible application for the water produced is rainmaking, which involves releasing the water produced from the stratosphere at a height where it will freeze before entering the troposphere where it would then melt again. This reduces the temperature and increases the relative humidity of the troposphere until it saturates and starts raining. The rain will in turn initiate a convection rain pattern, thus feeding even more humidity and rain into the system. This process could be used to alleviate water stress in regions suffering from shortages.


  • Hunt J, Byers E, Balogun A-L, Filho W, Colling A, Nascimento A, & Wada Y (2019). “Using the jet stream for sustainable airship and balloon transportation of cargo and hydrogen” Energy Conversion and Management: X. doi: 10.1016/j.ecmx.2019.100016



The idea that we can now consider using airships because we can predict the wind is interesting - a combination of the Hindenburg and Google's project Loon.
It still doesn't sound right to me.
You'll have to wait for the wind to be blowing in the right directions and it is difficult to get an airship up to the stratosphere.

Also transporting H2 by airship is a bit steampunk.
Would we not be better using high voltage cables and moving the electricity directly ?
Or build sea ships to do the job.

However, if you are interested in airships, I can recommend: "Dr. Eckener's Dream Machine" as excellent (amazon).


Put sails on hybrid ocean freighters.


However, it does pose the question - how should we transport large amounts of renewable energy over long distances?
For instance, moving solar electricity from North Africa to Europe, or moving electricity from the east to the west of North Africa.
Should we simply use HVDC lines or is there a better way ?
Should we convert it to some liquid fuel (Methanol ?) and move that in tankers ?
What do the group think...


For increased competition, the energy market is large enough for both technologies. Personally, I would prefer underground/underwater very high voltage DC/AC power lines without having to convert to liquid fuel.

Link to discussion paper PDF

How longs a price of string?
Seriously that is an important question for discussion but the specific situation o example will decided the answer. I think this will be a while away for many locations but could occur rapidly in some others.

Airships may not be as silly as it sounds but while compression may be avoided in a trade off for density, the receiving end will have to deal with it in some way.

Roger Pham

H2 can be far easily transported via pipelines, similar to the pipeline transportation of Natural gas.
Cargo transportation is most efficiently done by train on land, or by ships at sea. Period.


Ridiculous? H2 is the smallest known molecule; it'll diffuse through anything / everything. It is the "escape artist" among the elements. The higher the storage pressure, the higher and faster the losses will be.
The current- and highly polluting method of generating H2 is accomplished by cracking NG. CO2 is emitted to the atmosphere and is not cleaner than emitting CO2 via a combustion process.
H2 generation via electrolysis is emissions neutral but has an efficiency of 70% or 30% losses.
I suspect that overall system-losses of H2 via pipeline will be far higher than system losses of high voltage DC transmissions.

Roger Pham

Hydrogen has been transported via piping for over a century without problem. Before natural gas was discovered, cities used "town gas" which contains high proportion of Hydrogen. Town gas was made from coal gasification and was transported to each house via soft-steel piping system. When natural gas was discovered, then natural gas was used in the same piping system, instead of "town gas". Losses of Hydrogen in pipeline system has been negligible.

"cracking" of natural gas releases CO2 at high pressures and at high concentration that is ready for injection into depleting oil and gas wells, at almost NO further cost.
By contrast, CO2 sequestration from power plants is very expensive due to the high cost of separating the CO2 from the flue gas and compression of this CO2 at atmospheric pressure.
So, the best way to eliminate CO2 emission now is to make H2 from fossil fuel, and immediately sequester this CO2, while transport the H2 to the end users.

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