Next Big Trip

From alternative fuels to rationing trips: A guide to more sustainable flying

Julia Buckley, CNN • Updated 25th May 2022
(CNN) — As pandemic-related restrictions start to lift, and we emerge from the lockdown shadows, one thing is returning to the minds and spending of many people: travel.
If the current travel chaos is anything to go by, we're all dreaming of a vacation right now. There's just one problem. The climate crisis hasn't gone anywhere. Two years of hunkering down has been good for our carbon footprints, but returning to ambitious travel is a step in the wrong environmental direction.
Of course, we know the answer: stop traveling. Or, at least, stop flying.
But while the flight shame movement is growing, it's not for everyone. And just because you aren't prepared to make that sacrifice, doesn't mean you can't make smaller changes to ensure your travel is more sustainable.

What's the big deal about flying?

The aviation industry is growing at an unsustainable rate for the environment.
The aviation industry is growing at an unsustainable rate for the environment.
Stefani Reynolds/AFP/Getty Images
After all, aviation accounts for just 2.1% of manmade carbon emissions worldwide, according to the Air Transport Action Group, and 3.5% of planet-warming emissions in total. It doesn't sound so bad when you put it like that.
But it's not so simple, explained Matteo Mirolo, aviation policy officer at Transport & Environment, a European campaign group for cleaner transportation.
"You have to look at the growth of the sector. It's quite significant, despite Covid," Mirolo said. "Even after 9/11 or the 1970s oil crisis, aviation grows back stronger. Now it's growing again, and it's a largely unregulated sector."
"If we don't do anything now, in a few years aviation will be one of the most significant contributing factors. We shouldn't look at the snapshot now," he said, "we should look at the forecast."

Good news and bad

The problem is, so many of us want to fly.
The problem is, so many of us want to fly.
Evert Elzinga/EPA/Shutterstock
The good news? "Lots of solutions" are in the pipeline, Mirolo said.
The bad? They're not ready yet. Expect real results in "decades."
Sustainable aviation fuel, or SAF, is a future gamechanger, Mirolo said. But not all SAFs are created equal. What he calls "true waste residue" -- like the used cooking oil with which Airbus recently powered an A380 -- is "a real step in the right direction." Synthetic kerosene also works. However, some SAFs contain palm oil, which is linked to deforestation. In October 2021, Indonesia conducted a test flight powered by biofuel containing palm oil, as government officials spoke of the need to increase production of palm oil-heavy biofuels.
Neste, a biofuels company which sells SAF to the likes of American Airlines, KLM, Lufthansa and Delta, uses palm oil in its non-SAF biofuels, though a company spokesperson says that it is sustainably sourced and will be phased out by the end of 2023. Using palm oil as fuel said Mirolo, is "a cure worse than the disease."
And although flying a plane fueled by used cooking oil is in the testing stages, we're decades from it happening commercially. The UK government, for example, has proposed mandating that all planes filling up in the country must fuel with up to 10% SAF by 2030 and up to 75% by 2050. The EU is mulling a mandate of 2% SAF by 2025 for planes departing from European Union airports, while Japan is aiming for 10% SAF by 2030.
That's all unconfirmed, as yet. The only SAF mandates currently in place are Norway, Sweden and France, each of which oblige carriers leaving the country to use 1% SAF.
Meanwhile, we're looking at around 2030-35 for the introduction of hydrogen-powered planes, if we're being optimistic, said Mirolo. Even when they're introduced, they'll only be capable of flying under 2,000 miles -- meaning they won't be viable for long-haul flights.
As for battery-powered planes, again, 2030 would be optimistic, said Mirolo, and they are likewise unsuitable for long journeys. An hour's flight is currently the limit for a 100-seater plane. Plus, he said, we'll have to work out the climate impact of building and changing batteries -- they may not be as great as we think. Hydrogen and electric planes could cover around 20% of the projected passenger demand by 2050, he says -- which is why he thinks SAF is a better bet.
Mirolo said that airlines that trumpet their carbon offsetting schemes are ones to avoid. "Carbon offsetting was in fashion a few years ago but we know it's not the solution -- the solution is SAF," he said.
Mike Childs, head of science, policy and research at environmental organization Friends of the Earth, previously described carbon offsetting as a "massive con" to CNN, partly because any effect from offsetting is years off (and might never occur) and partly because efforts to reforest are already being made. Today, "nothing has fundamentally changed" with the schemes, he said.

Bottom line: Fly less

Try returning to seeing flying as a treat, rather than your go-to.
Try returning to seeing flying as a treat, rather than your go-to.
iStockphoto/Getty Images
Experts are realistic and acknowledge that most people will feel the need to fly sometime. As Childs put it: "None of us are angels."
"This isn't a discussion about whether we should fly or not, but about reducing the amount of carbon emissions from flying," said Justin Francis, CEO of Responsible Travel, which sells sustainable vacations around the world.
Francis believes travel broadens minds and helps local communities, but says many are doing too much of it. Instead of jumping on every cheap flight we get an alert for, Francis suggests we roll back to a time when getting on a plane was a treat.
We need to get out of the mindset that we need to fly so much, these experts say. Childs said that boarding a plane should be our last option. "The best thing to do is rail, or, mile for mile, even driving is going to be better," he said.
Mirolo said that each time we plan a trip, we should "think twice about flying." Can you go by another method of transport? If it's a business trip, is an in-person meeting essential or can you do it remotely? "You have to decide whether you're going to take that plane. It's not about stopping flying altogether, but being reasonable."
"Our position is to encourage people to take longer holidays, which will mean fewer flights total," said Francis. "A longer trip is more relaxing and enjoyable, and carbon does need to be top of our minds. We need to choose big trips more consciously and use other forms of transport to travel closer to home.
"For me, instead of two long-haul flights a year I might still go to Vietnam, but for one of my longer trips I might do a slow travel train trip to Italy."

Trains and buses

Traveling on the surface of the Earth will always be better than flying.
Traveling on the surface of the Earth will always be better than flying.
Amtrak
Of course, it helps that Francis is based in Europe, where high-speed train travel is the norm. But even if you're somewhere with limited public transportation, like the US, it's still better to avoid flying, said Childs.
He reckons that a long cross-country US road trip, say, from Washington, DC to Yellowstone National Park, will be less harmful to the environment than a quick flight to the Caribbean.
"If you've no option to go by train or public transport, and you've got a choice between driving and flying somewhere, then driving will always be the better option," he said. "It's easier to shift a body in a big lump of metal by road than by sending it up into the air and keeping it there... One day there may well be greener forms of flying a short distance, but right now go on the surface where you can."
And the more often that surface transport is public (i.e. trains, buses) the better.

How to fly

Last year Airbus revealed a trio of hydrogen-powered zero-emission airliner concepts, under the banner ZEROe, which could enter service by 2035.
Last year Airbus revealed a trio of hydrogen-powered zero-emission airliner concepts, under the banner ZEROe, which could enter service by 2035.
Airbus
For those of us who've been lucky enough to fly business class, going back to economy is hard. But economy is the greenest way to fly -- and budget airlines that cram as many seats in as possible are the most efficient planes in the sky.
Premium seats made up just 5% of international traffic in February 2022, according to the International Air Transport Association, yet premium seats take up far more room on a plane. For instance, all-economy Wizz Air has 239 seats on its A321neo aircraft, whereas its European rival Lufthansa, which has a shorthaul business class, operates the same plane configured for just 215 passengers. Both fly the A320-200, too -- Lufthansa's version has 168 seats, while Wizz's crams in up to 186 passengers.
On shorthaul routes the difference between business and economy class is likely to be a wider seat and maybe a bit more legroom, but long-haul configurations change the dynamics entirely, with space for lie-flat beds and even entire "suites" on the likes of Emirates and Singapore Airlines, each taking up the equivalent of several rows of economy class.
Both Singapore Airlines and Emirates fly the A380, for example, but the former puts economy and premium economy on the top deck; the latter reserves it for business and first class. The difference? Singapore Airlines fits a total of 399 passengers on its top deck; and Emirates, just 90, in the same space.
Business and first class components tend to be much heavier as well, with chairs sitting in fixed "shells," and sometimes closable doors for each seat.

Budget carriers are greener -- on paper at least

Looking at the expansion of budget airlines, they're less green than you imagine.
Looking at the expansion of budget airlines, they're less green than you imagine.
Jason Alden/Bloomberg/Getty Images
The European carrier Wizz Air calls itself the "greenest" airline on the continent, thanks to its young, modern fleet, pile-'em-high, all-economy seating philosophy, and its undertaking to only fly direct. They also don't offer any routes for which there's a rail alternative in under four hours. Wizz claims the lowest CO2 emissions per passenger kilometer in Europe and tells passengers, "If you don't need to fly, please don't."
However, that's not the whole picture, said Mirolo. Low-cost carriers "are the ones growing very fast," he explained -- so while their metrics per passengers look good, they're a major part of aviation's problematic expansion.
When it comes to legacy carriers, he said that long-haul flights are the issue -- with 5% of flights representing 50% of emissions. The EU's proposed SAF mandate applies only to aircraft departing from EU airports -- which means that while flights within the bloc would be covered, the mandate would only apply to half of long-haul flights (those leaving the EU, but not coming in).
That's why Mirolo recommends concerned passengers put their money where their mouth is, booking flights with airlines who've been investing in, and already using, SAF in a "credible" way. Those include United, Alaska, Qantas and SAS, which even allows passengers to buy "blocks" of biofuel alongside their flights, and are rewarded with extra miles if they do so.
Air France-KLM is bound by the 1% SAF mandate for flights leaving France, but since January has committed to 0.5% SAF in every plane departing their Amsterdam Schiphol hub, too. A surcharge (€1-€10) is applied to tickets.
Mirolo also said concerned fliers should be using their vote to make the aviation industry more sustainable. "There's unprecedented political will to make [sustainable aviation] happen, and real movement, so vote with your ballot, and then vote with your feet."

Private jets are ruinous -- but could also help

New tech is most likely to happen on smaller planes first -- so the private jet market could help.
New tech is most likely to happen on smaller planes first -- so the private jet market could help.
Eviation Aircraft
For most of us, the closest we'll get to flying in a private jet is watching celebrities' social media posts. But just because it's a method of travel for the elite, doesn't mean it's not affecting all of us.
A 2021 study by the environmental nonprofit Transport & Environment, found that 1% of people were responsible for half of all global emissions from flying. The private jet industry is booming, expanding by 31% between 2005 and 2019. What's more, 40% of private flights are "ghost flights" -- empty of passengers as they reposition for their next pick-up.
Because private jets tend to make short hops, that makes them even less environmentally sustainable. The shorter the hop, the less necessary it is, too. "For 80% of the most popular (private jet) routes in Europe, there's an alternative by train," said Mirolo, adding that according to his tally, 10% of flights taken in France are now private.
The good news, however, is that, because of their smaller size, private jets can be at the forefront to adapt to new technology as it comes on the market. That, in turn, could help the market move forward, faster.
"The super rich can super charge the decarbonization of aviation by investing in these kind of planes," said Mirolo, referring to electric and hydrogen-fueled planes. And if they do that, the 1% will help the 99% fly more sustainably.