Near-Zero Aviation Is Possible, But Do We Have the Will?

It requires a level of political will that’s rarely been seen thus far.

airplane on a runway
Jaromir Chalabala / EyeEm.

I confess I got quite excited when Norway started talking about supporting electric planes, not to mention when DHL bought some to start moving cargo around. After all, as a self-confessed climate hypocrite with family all over the world, I have a vested interest in the pathway toward low-carbon aviation. So my ears pricked up when I heard the International Council for Clean Transportation (ICCT) was releasing a report called "Vision 2050: Aligning Aviation with the Paris Agreement."  

And the report makes for interesting reading. Covering scenarios that range from a baseline business-as-usual to a "breakthrough" option that’s marked by aggressive and early government action, it clearly shows that "near-zero" emissions are possible by 2050. Here’s a basic breakdown of the various scenarios presented—ranging from inaction to modest efforts to a truly aggressive push.

Graph of global aviation CO2 emissions
WTW global aviation CO2 emissions by scenario and traffic forecast from 2020 to 2050.


Interestingly, given the sheer amount of lip service paid to electric aircraft and hydrogen in the blogosphere, in all three of the scenarios not represented by business-as-usual, by far the biggest piece of emissions reductions is attributed to sustainable aviation fuels (SAFs). The main difference, then, is how far and how fast governments are willing to push SAFs and impose a price on fossil fuels, to account for differences in price. (Zero carbon hydrogen and electric planes, as well as operating efficiency, do also put a dent in emissions in the two most aggressive scenarios.)

In order to have any hope of staying within a pathway that’s consistent with a 1.5 degree Celsius temperature rise, the report’s authors say immediate government action is required and emissions would need to peak this decade.  

Graph of Cumulative global aviation CO2 emissions by scenario and measure, 2020-2050
Cumulative global aviation CO2 emissions by scenario and measure from 2020 to 2050.


What’s also clear, however, is this transition is going to cost a lot of money. And that means ticket prices are likely to go up—especially in the more ambitious scenarios that would require government intervention to address the mismatch in prices between fossil-fueled flights and more sustainable alternatives. Here’s how the report’s authors describe that challenge in the executive summary: 

“Under all scenarios, fuel and ticket costs rise along with the introduction of SAFs. Under the Breakthrough scenario, fuel costs increase by 34% and 70% in 2030 and 2050, respectively, due to the adoption of these more expensive fuels. Thus, policies like a SAF mandate, low carbon fuel standard, carbon taxes, and/or a frequent flier levy will be needed to bridge the price gap between alternative and fossil jet fuels.”

For folks like me, who would quite like to feel less guilty as we fly home to see family and drink proper beer, the report’s findings do offer a glimmer of hope. They also, however, are a sobering reality check: Even though the most ambitious and optimistic scenario suggests near-zero aviation is possibly by 2050, it requires a level of political will that’s rarely been seen thus far. Not only that, but even if fully achieved, this scenario would still be inconsistent with a 1.5-degree temperature rise once cumulative emissions are taken into account. 

Graph of WTW global aviation CO2 emissions by scenario and traffic forecast, 2020-2050
The solid line depicts the central traffic forecast, while the shaded area depicts the range between the low and high forecasts.


So where that leaves is here: In order to stave off the worst impacts of climate change, without burdening other sectors like food and energy from having to go even faster in getting to zero, decarbonizing aviation is going to require either significant direct air capture to offset emissions or a far more robust effort at actually curbing demand. (The report does envision a slight dent in demand due to higher prices.)

When I interviewed one of the report’s co-authors, Dan Rutherford, about the future of aviation, he was pretty clear that flying less and flying more efficiently should not be viewed as an either/or choice. In fact, as the pandemic-related changes in air travel have shown us, it’s perfectly possible to achieve many of the societal functions of aviation through the smart use of alternatives. While I, personally, have failed to entirely give up flying, I have seen business-related travel slashed at my day job, and I’ve helped advise another company that’s aiming for a 50% reduction in travel now that conferences are back on the menu. 

Given that a tiny minority of travelers make up for the vast majority of travel, it seems feasible to me that a concerted effort in taxing frequent flying, investing in and incentivizing alternatives, and raising awareness about the impact of air travel could help move us forward. Now we just need political leadership that’s willing and able to face the inevitable conclusion: Continued growth in aviation is simply not compatible with stabilizing and drawing down emissions.