“Absolute Zero” report by UK academics: the only way to hit net zero by 2050 is to stop flying

In probably the best, more sensible (and most radical) comments on the future of aviation to date, Professor Julian Allwood (Cambridge University) and a group of academics from 6 UK universities, say there is no alternative but to cut aviation drastically. It is futile for the industry to hope for electric planes (which just might be a possibility by 2050, but only IF there is spare low-carbon electricity available). It is futile for airlines to pretend they can use low-carbon fuels, (these could only be made IF there is spare low-carbon electricity available). And it is unacceptable to pretend CO2 emitted is going to be captured, removed from the atmosphere, and stored. Not without vast use of energy. Tree planting only goes so far: we must increase the total area of forest in perpetuity to produce a one-off reduction in atmospheric CO2.  The academics suggest closing most UK airports by around 2030, and closing just about all by 2050, to genuinely have no carbon emissions (offsets do not count). Only if there is spare low-carbon electricity available after 2050, could flying re-commence using electric planes or genuinely low carbon fuels. They say: “Bold announcements of “net-zero” targets by sunset industries such as fossil-fuel aviation cause confusion and delay the policies required to phase them out.” 


The only way to hit net zero by 2050 is to stop flying

Dreaming of electric planes and planting trees will not save our planet

(Financial Times)

By Professor Julian Allwood (Cambridge University)

The writer is professor of engineering and the environment at Cambridge university

The UK aviation industry this week promised to bring its net carbon emissions down to zero by 2050 while growing by 70 per cent, and Prime Minister Boris Johnson boldly predicted that “viable electric planes” would be available in just a few years.

But past experience with innovation in aviation suggests that such ambitious targets are unrealistic and distracting. The only way the UK can get to net zero emission aviation by 2050 is by having a substantial period of no aviation at all. Let’s stop placing impossible hopes on breakthrough technologies, and try to hit emissions targets with today’s technologies.

Our recent report “Absolute Zero” draws on work at six British universities to explain how.

There are three ways to deliver net-zero aviation: invent new electric aircraft, change the fuels of existing aircraft or take the emissions out of the atmosphere.

Electric planes already fly. Solar Impulse 2, powered by solar cells flew one person round the world in 2016, but slow progress in photovoltaics mean this is unlikely to scale up. Demonstrations of short battery-powered flights with a few passengers will soon begin. However, the technology is in its infancy and aerospace is, rightly, a highly regulated industry. Commercial long-haul electric flights will not be operating at any significant scale by 2050.

Alternative fuels, such as hydrogen or synthetic kerosene, only deliver zero emissions flight if their production is powered by renewable electricity. Right now, green sources supply about 15 per cent of the world’s primary energy consumption. Over the next 30 years, while road vehicles, heating and industry are being electrified, there is unlikely to be spare clean power to make aviation fuel.

Finally, there are currently no meaningful negative emissions technologies. It requires more energy to recapture carbon dioxide from the atmosphere than was generated when it was released. Using renewable electricity to power carbon capture rather than to displace fossil fuels does not create a net reduction. And tree planting only goes so far: we must increase the total area of forest in perpetuity to produce a one-off reduction in atmospheric carbon dioxide.

So the commitment to net zero aviation by 2050 is really a commitment to zero aviation. Rather than hope new technology will magically rescue us, we should stop planning to increase fossil-fuel flights and commit to halving them within 10 years with an eye toward phasing them out entirely by 2050.

Taxing aircraft fuel at the level of the UK’s current road fuel tax would be a useful first step: I estimate that it would make flights up to four times more expensive.

Climate policy announcements so far have failed to account for the limited rate at which new technologies can reach significant scale. Fifty years after the Danes began developing wind turbines, they contribute just 2 per cent of world primary energy. Regardless of prices or incentives, new energy generation, transport and industrial processes require public consultation on regulations, land use, funding, environmental impacts and more. This all slows down their adoption.

We should embrace this reality and focus on innovations that are compatible with a zero-emissions future. Video-conferencing software cuts the need for travel but is undeveloped. Average car weight has risen steadily since 1990 and could be halved. Scrap steel is collected with little sorting and recycled into low-grade products, but it could be upcycled in renewable powered furnaces.

Bold announcements of “net-zero” targets by sunset industries such as fossil-fuel aviation cause confusion and delay the policies required to phase them out. They also distract us from innovations that can be implemented rapidly and buy us the time we need to develop real zero-emissions options.



See also

The report is by a group of academics in universities of Cambridge, Oxford, Nottingham, Bath, Strathclyde and Imperial College.  Their comments on aviation are interesting … and extremely ambitious …

Blurb at https://www.repository.cam.ac.uk/handle/1810/299414

Report at
Lead author is Julian Allwood, at Cambridge. https://www.caths.cam.ac.uk/directory/professor-julian-allwood  (author of article above)
They say between 2020 and 2029 :
“All airports except Heathrow, Glasgow and Belfast close with transfers by rail”
Then between 2030 and 2049
“All remaining airports close.”
Then we reach Absolute Zero by 2050
Then after 2050
“Electric planes may fly with synthetic fuel once there are excess non-emitting electricity supplies,”

By contrast, this is the UK government position:


Photo of Nusrat GhaniNusrat Ghani Parliamentary Under-Secretary (Department for Transport), Government Whip

[….bit about ports first ….]

The Airports National Policy Statement was designated as government policy in June 2018 following a vote in the House of Commons. It sets out that there is a need to increase airport capacity in the South East of England by 2030 by constructing one new runway and that this need is best met by the Northwest runway scheme at Heathrow Airport. It requires that at least 740,000 air transport movements are delivered at Heathrow per annum.

The Northwest runway scheme would enable Heathrow to nearly double its current freight capacity, it would also lead to better domestic connectivity by securing at least 14 domestic routes.

The Government is also supportive of airports making best use of their existing capacity, subject to the assessment of the merits of individual applications, including consideration of their environmental impacts. The Government set out its policy position for the South East of England in Beyond the Horizon: The future of UK aviation: Making best use of existing runways.

These policies make clear that the government considers that potential airport growth applications should be considered under the appropriate planning regime and should take careful account of all relevant considerations, particularly economic and environmental impacts and proposed mitigations.