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ZeroAvia plane -

In the late summer of 2020, a commercial-scale hydrogen plane took off from Cranfield airport in the UK. To everyone’s relief, the flight was uneventful.

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ZeroAvia plane -

The six-seater Piper M-Class plane was developed by the California-based start-up ZeroAvia, in conjunction with its partners in the UK and elsewhere around the world.

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Step in the right direction -

The successful first flight of the hydrogen plane represented a significant step forward in the move towards zero-carbon aviation.

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The problem -

Before the COVID-19 pandemic put a stop to the majority of flights, commercial aviation was responsible for around 2.5% of global carbon dioxide emissions.

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The problem -

This may not sound like much, but in fact it is more than the total emissions of the country of Germany, which is responsible for 2.2% of emissions globally.

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Reason for hope -

Unsurprisingly, then, there is a lot of interest in improving efficiency in the aviation sector. Thankfully there is reason to hope that a lot can be achieved.

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Reason for hope -

Since 1990, carbon dioxide emissions per passenger flight have dropped more than 50%, thanks to significant improvements in both engines and operations.

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Increase in air traffic -

However, this has been countered by an increase in air traffic, which has increased by at least 20% over the past five years.

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Hydrogen as a fuel -

Hydrogen appears to be a good option when it comes to powering planes that don’t destroy the planet. It can be used as a fuel in one of two ways.

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Very clean -

Hydrogen can be used as a fuel cell to generate electricity or it can be combusted directly for motive power. Either way, the only waste product is clean water.

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Investment opportunity -

Both governments and companies are investing in hydrogen-powered planes. The 2020 ZeroAvia plane was supported by the UK government, for example.

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Investment opportunity -

The UK government, in conjunction with private investors and commercial partners, is currently supporting ZeroAvia in the development of larger hydrogen-electric aircraft.

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ZeroAvia of the future -

This plane will be able to carry up to 20 passengers for 350 nautical miles (648 km). ZeroAvia’s founder and CEO Val Miftakhov has high hopes for this model.

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ZeroAvia of the future -

He says that the company expects to offer commercial flights using this aircraft by 2023, and by 2026 it will have an aircraft that can carry 80 passengers around 500 nautical miles (926 km).

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Airbus project ZeroE -

There is also interest in Europe. In September 2020, Airbus, the world’s biggest aircraft manufacturer, announced ZeroE, a project that has hydrogen-fueled propulsion systems at its core.

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The three planes -

ZeroE currently consists of three concept planes, which according to Airbus could be ready for deployment by 2035. All three designs are hydrogen hybrids.

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The three planes -

This means that they will be powered by combusting liquid hydrogen as a fuel, as well as by the electricity generated via hydrogen fuel cells.

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Planes 1 and 2 -

The first ZeroE plane will be able to carry around 100 passengers for about 1,000 nautical miles (1,850 km), and the second around 200 passengers for about 2,000 nautical miles (3,700km).

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Plane 3 -

The third plane, which will look decidedly different from the aircraft of today, may be able to carry more passengers over a longer distance, but more details have not yet been released.

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Challenges -

However, the move towards hydrogen planes does not come without its challenges. Firstly, hydrogen has lower energy by volume than jet fuel because it is typically in gas form.

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Low energy by volume -

This means that it must either be compressed or turned into a liquid and then stored in tanks that are complex and heavy.

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Low energy density -

Secondly, the energy density of liquid hydrogen is much less than that of jet fuel. For the same amount of energy, it needs to be stored in a tank four times the size.

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Low energy density -

This means that hydrogen planes will need to carry fewer passengers, or be made considerably larger. There is also the issue of storing hydrogen at airports.

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The problem of production -

Furthermore, it is difficult to produce hydrogen competitively and at scale without generating a large carbon footprint. Currently most hydrogen is produced using fossil fuel methane.

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Doubts -

It is due to these factors that some major players in the industry have doubts as to whether hydrogen is the best option in the move towards zero-carbon aviation.

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Doubts -

According to David Joffe of the Climate Change Committee, which is an advisory body to the UK government, "Switching to direct hydrogen adds decades into the transition."

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Other options -

According to the Geneva-based Air Transport Action Group, more important in the move towards zero-carbon aviation will be so-called “sustainable aviation fuels” or “SAFs.”

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Sustainable aviation fuels -

The term “SAFs” is a cover term to catch all products that result in low net emissions of CO2 and other pollutants that are associated with jet fuel.

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Sustainable aviation fuels -

According to the advocates of SAF, they have a number of advantages over hydrogen, including the fact that they are chemically identical to jet fuel and can be “dropped in” to current systems.

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Conclusion -

Whichever path the aviation industry chooses to take, it is clear that for now the role of hydrogen is limited due to the fact it is considerably more expensive than jet fuel.

Sources: (BBC)

See also: Iconic flight and aviation movies

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