Aviation’s climate pledges contradicted by huge growth forecasts

The aviation industry is aiming for “carbon neutrality by 2050” while continuing to expand. While it hopes to make small reductions in carbon per passenger kilometre travelled, by efficiency gains and novel energy sources, most of the “carbon neutrality” would have to be from offsets, or carbon storage.  There are currently no viable means of propelling commercial airlines large distances, without causing the emission of a lot of carbon. That situation is unlikely to change for at least another 40 years. In the meantime, it is imperative that global carbon emissions reduce fast, year by year, from now onwards.  Not from 2050.  Transport & Environment says relying on ICAO and its CORSIA (ineffective) scheme to achieve net-zero in the long-term will be just another distraction from real measures to clean up flying in the near term. Relying on rapid deployment of yet-to-be-deployed Sustainable Aviation Fuels (SAF) and zero-emissions technology is harmful, as large-scale deployment is many years away. Assuming solutions are just around the corner would unjustifiably, and damagingly, allow high levels of air travel to continue.  Flying less is the most effective way to reduce aviation emissions.


Aviation’s climate pledges contradicted by huge growth forecasts

NOVEMBER 26, 2021

By Transport & Environment (T&E)

Can the aviation sector honour its pledge of carbon neutrality by 2050 while continuing to expand?

In the the next two decades, Airbus sees the need for some 39,000 new passenger and cargo aircraft. Yet the company claims that continued improvements in fleet efficiency, sustainable fuels, and propulsion technologies will make the sector’s 2050 net zero objective possible.

Progress on these measures so far is slow, which, T&E says, casts doubt on the industry’s ability to reach its mid-decade zero-emission targets.

Recent pledges made at COP offer no reassurancesRelying on ICAO and its carbon offsetting scheme to achieve net-zero in the long-term will be just another distraction from real measures to clean up flying in the near term, warns T&E.

Relying too heavily on yet to be deployed Sustainable Aviation Fuels (SAF) and zero-emissions technology could also prove harmful, given that their large-scale deployment is many years away. 

Andrew Murphy, aviation director at T&E, said: “It will take years to ramp up SAF production and even longer to develop zero-emissions propulsion technology. Right now, flying less is the most effective way to reduce aviation emissions.”

Back in 2010 IATA, a trade association of the world’s airlines, committed to using 10% sustainable aviation fuels (SAF) by 2017. Twelve years later, the sector’s emissions are still expected to triple by 2050 and the current use of SAFs in the EU is estimated to be just 0.05% of total jet fuel consumption.

Similarly, plans for zero-emissions technology offer no immediate solution to reduce aviation’s emissions, with at least 10 years needed to scale it up. T&E makes it clear that the sector does not have 10 years to find a solution. 

“Flying is a great way to connect Europe and the world. But because industry and regulators have dragged their feet in decarbonising the sector, flying less is the most effective measure to reduce emissions until new technologies are deployed at scale,” says Andrew Murphy.

Unsurprisingly, flying less is not part of the airline industry’s net zero vision. IATA estimates that air traffic will grow by 3 per cent a year between 2019 and 2050. This, despite research demonstrating that growth in aviation is incompatible with a net-zero goal by the mid-decade.  

“IATA’s goal is unrealistic. Not because SAFs are unrealistic, or because of the numbers, but because nowhere in their forecasting are they accepting that aviation shouldn’t grow as much as is predicted,” concludes Murphy.



See also

Stop greenwashing of aviation: 5. E-fuels


Producing e-fuels would require huge quantities of renewable electricity that would deprive all other sectors that need to decarbonise

E-fuels could be part of a new economy of hydrogen aiming at replacing fossil fuels where electricity is not a possible alternative. But their production would require huge quantities of renewable electricity: not only must hydrogen be produced from electricity with significant energy loss, but making synthetic fuels from hydrogen requires further process steps with even higher energy losses. Hydrogen needs to be combined with CO2 and the resulting fuel must be processed and purified to make it usable by aircraft engines. CO2 must be extracted from the atmosphere using “Direct Air Capture” (DAC) at high energy cost due to its dilution. No more than about 10% of the electricity spent would be converted into thrust to move an aircraft.

Using renewable electricity to make e-fuel therefore looks like a crazy idea because energy requirements would be huge, whereas renewable electricity is crucially needed to decarbonise the global economy and can be used with a far higher efficiency in most other applications. For example, electricity powering a battery-electric coach results in an approximate 77% power-to-motion efficiency, which is 8x better than if used for an e-fuel powered flight in an aircraft! For the decades to come, the production capacity of renewable electricity will still not be enough to:

  • Replace fossil fuel in power plants that supply the electricity grid
  • Help satisfy new demand for electricity (cars, heating/cooling, data, etc.)
  • Replace today’s grey hydrogen (produced from fossil fuels) used for industrial processes e.g. fertiliser production
  • Satisfy new demand for hydrogen for trucks, ships, aviation…


Se also

House of Commons Library briefing.

Aviation, decarbonisation and climate change

The government is NOT keen on measures that limit demand for flying.



The Climate Change Committee says:

The CCC has said that “[in] the absence of a true zero-carbon plane, demand cannot continue to grow unfettered over the long-term”. Their scenarios reflect a 25% growth in demand by 2050 compared to 2018 levels.25 This is significantly lower than Government projections (published in 2017) for up to a 49% increase in demand over the same period.26 Both of these projections are significantly lower again than the UK aviation industry’s claim that there are sufficient measures to support a 70% growth in passenger numbers by 2050 and still meet the a zero target.27 In May 2021, Aviation Minister Robert Courts said The Department would “look to publish new long-term aviation forecasts in due course” once the Covid-19 recovery has settled down.28


But the report continues:

Demand management and taxation

In September 2019 the Chair of the CCC, Lord Deben, highlighted to the Secretary of State for Transport, Grant Shapps, the opportunity for further emissions savings from additional demand constraint, i.e. limiting passenger growth to less than 25% above current levels by 2050. The CCC argued that this could be driven by future changes in consumer preferences and social norms, or by more ambitious policy.191 In a report on behavioural change and aviation for the CCC, Dr Richard Carmichael of Imperial College London argued that it is vital to constrain rising demand, despite the political challenges of this:

Sensitivity about pricing annual holidaymakers out of the sky has discouraged greater taxation on flights and policy has not addressed rising aviation demand. However, well-designed fiscal measures could offer effective, fair and publicly acceptable means to confront the risk of unrestrained growth in demand in the absence of alternative low-carbon aviation technologies. Fairness and how impacts are distributed are of key importance to public acceptability of policy in general…and will be especially important for aviation.192

However, the aviation industry and its supporters say that there are compelling economic arguments in favour of continued growth (see section 1.3). The Government, moreover, in its Jet Zero Strategy says it “is committed to tackling the CO2 emissions from flights, whilst preserving the ability for people to fly.” It says its own analysis shows that, “there are scenarios that can achieve similar or greater CO2 reductions to those in the CCC’s Balanced Pathway […] focussing on new fuels and technology, with the knock-on economic and social benefit, rather than capping demand.”193