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The Future of Air Travel - 1 The story so far...

 Tesla of the Skies? NASA's Maxwell X-57 zero emission, two -seater electric plane is set to take off in February 2022

This Photo by Unknown Author is licensed under CC BY


I was hoping to bring you lots of good news about flying. I love flying. It was amazing being able to visit family or places I'd only seen in National Geographic or on the screen, and I’ll never forget my mother's tearful reunion with beloved people and landscapes she hadn’t been able to see for 25 years after she left for Australia. That wasn't possible before cheap flights came along in the 1970s.

For short haul flights, things are looking quite good. I see for example, where two Australian tourist operators have ordered 60 electric planes between them for flights around Sydney and the Barrier Reef, yet for those long flights which we need to get out of Australia, not so much. Here’s what I’ve learned so far.

 So what’s wrong with flying anyway?

Aviation accounts for 2.3% of global emissions which again doesn’t sound very much, but this is not only the equivalent of one million homes, but is expected to increase enormously over the next few years. Aviation alone could push emissions up above 1.5%, negating emissions in other sectors, unless emissions are reduced by 60%. Researchers at the Smithsonian have calculated that a fully laden 747 travelling around 5,000 KM produces less CO2 than the same number of people travelling the same distance by car, but  short haul flights produce more because take - off and landing use more fuel. This is why France has banned flights to places which can be reached by rail in under three hours (see the section on trains). Smaller planes, like smaller ships, also produce proportionately more CO2, as do only partially laden ones. However, CO2 is not the only problem.

According to scientists, the soot, nitrous oxides and particulates released in the upper atmosphere by the exhausts of planes contribute far more to global warming than CO2 does. They do this by encouraging the formation of clouds which, while they reduce some of the solar radiation reaching earth, also trap accumulated heat underneath and stop it escaping into space -a perfect example of the greenhouse effect.


In 2009 the International Airline Transport Association – possibly fearing external regulation, outlined strategic targets for the industry which included carbon neutral growth by 2020, net reduction of CO2 emissions by 50% compared to 2005 levels by 2050. In 2016, the UN established  CORSIA – a Carbon Off-setting Scheme for International Travel. This requires participating countries to offset increases in their carbon footprint from 2020 onwards. They can do this by investing in things such as renewable energy projects or tree planting. By 2019, 88 countries representing 77% of the industry and including the USA, had signed on. See more on this here.

Critics argue that while great in theory, this leaves untouched the CO2 which is already in the atmosphere and that offsetting, which was to be a measure of last resort, has now become the default position and is instead stalling action on real change.

Nevertheless, like shipping companies, many airlines and aircraft manufacturers are doing their best to reduce their emissions, though progress has not been as rapid as in other fields.

Electric, and Hybrid Planes

Companies such as Norway’s Avinor, Israel’s Eviation and even NASA, are experimenting with batteries and have succeeded in launching electric prototypes, but batteries are still too heavy to be considered for longer flights or larger planes. 

  • Easy Jet is partnering with Siemens and Rolls Royce to develop a plane capable of taking around 100 hundred passengers up to 500 Km, but these are unlikely to be in operation before 2030. In the medium-term hybrid models of various types are likely to hog the field, since they only require modification rather than complete redesign.
  • United Airlines through its offshoot, ZeroAvia has also managed to fly a six-seater hydroelectric plane in late December 2020 and is planning to retrofit 200 of its short distance commuter aircraft with emission free engines by 2028. In the meantime, it is focusing on having hydrogen fuel cell planes capable of taking 10 – 20 passengers by 2024, with 40 -80 seat aircraft coming on stream by 2028. ZeroAvia is not relying on offsets to reach its 2050 zero emissions target.
While possibly workable for regional flights, it would take trillions of $$$ to set up the necessary charging infrastructure and there would be intense competition from other sectors such as shipping. Much the same goes for the use of other fuels such as ammonia which would require redesign of planes and infrastructure. How much mitigation occurs also depends on the energy used to generate them. Unfortunately, revenue falls due to the pandemic have greatly slowed development and production,  


In the meantime, biofuels offer the best hope since they don't require modification of existing planes. At present at least 30 airlines are trialling or using biofuels as part of their fuel mix and they have shown great promise.

  •  Alaska Airlines was the first to use a 20% biofuel component in 75 of its commercial flights in 2011 and promised to use biofuels at least one airport by 2020.

  •   In 2019 United Airlines used a 30% mix to fly from Los Angeles to Chicago. Since then it has invested $US 40 million in further development and contracted to purchase $US 10 million worth of biofuel a year. Delta Airlines has likewise agreed to buy $10 million worth of the fuel and to invest $US 2 million in R and D.
  • Also in 2019, Sweden’s SAS airlines gave passengers the option of paying extra for flights using biofuel. It sells these in 10 blocks for each 20 minutes in flight and uses the money raised to buy more biofuel. SAS has set itself the target of reducing its emissions from aviation by 25% by 2030.To this end it has also reduced its emissions by eliminating the on – board duty free purchase option, thereby reducing weight and thus fuel needed to operate. 
  • Dutch KLM has also contracted with Neste to purchase 75,000 tonnes of biofuel beginning in 2022. It is also the only European airline carrier which regularly uses biofuel on intercontinental flights, particularly its Amsterdam to Los Angeles flight. It is now building a facility near Amsterdam's Schiphol Airport which will mainly use used cooking oils and the like. It also has a program for businesses to be able to ensure that at least some of their flights use biofuels.

However, there are a number of problems with biofuels too, the first being getting enough of it. There is already steep competition from other sectors such as shipping and road transport and it is 3-4 times as expensive as conventional fuels. For a pilot's take on this see below, though his reasons for wanting us to keep on flying, may not be entirely unbiased. 





As well as concerns about its origin  and processing -e.g. much is derived from palm oil leading to deforestation or encroachment on land needed for growing food, while how emission - free it is depends on the kind of energy used in its manufacture -renewable or non renewable. Nor is there at this stage any guarantee that it will produce less non – CO2 effects when flying at high altitude. 

The scariest thing is perhaps the projected increase in air traffic. Despite the drop because of the pandemic, biofuels would still add 2.5 Giga tonnes of CO2 to the atmosphere if the industry roars back to the levels predicted in 2019. Any gains from reducing emissions would quickly be taken up.

 Alas, for the moment it looks like the dream of guilt -free, affordable long -distance flight seems to be receding into the distance. Yet there are also some glimmers of hope. We’ll talk about those next time.
In the meantime, keep well and keep your fingers crossed.