Refuel, airplane, Cepsa, Spain
An operator refuels an airplane. Photo credit: © Joaquin Corchero/Contacto via ZUMA Press

A hard-nosed look at the chance of achieving zero-emission aviation by 2050: new tech, alternative fuels, and diverse solutions, all amid uncertainty, rising costs, and limited access.

On this week’s WhoWhatWhy podcast, Jeff Schechtman talks with British journalist and historian Christopher de Bellaigue about his book, Flying Green: On the Frontiers of New Aviation. De Bellaigue lays out the almost unattainable goal of the aviation industry to achieve zero emissions by 2050 and examines the questionable sincerity of the industry’s commitment to reducing its significant carbon footprint.

While the industry claims dedication to greening aviation, de Bellaigue argues that considerable progress is still needed. He identifies sustainable aviation fuels (SAF) as a potential early solution, since they are compatible with existing airframes. Hydrogen emerges as another possible fuel source for the transition’s intermediate stage but conversion to hydrogen fuel requires massive investment and airport reconfiguration, which is very unlikely. Electric planes, considered the pinnacle of green aviation, face limitations due to inadequate battery technology for long-distance flights.

He underscores the importance of developing new engine technologies and redesigning airplanes for alternative fuels to meet the net-zero goal. Surprisingly, he notes that the greatest progress has come from cargo companies like DHL, FedEx, and Amazon. 

De Bellaigue also talks about cutting-edge emerging technologies, and while SAF and biofuels show promise in the US, Europe is advancing in electrofuels, which combine carbon dioxide extracted from the air with hydrogen. 

In the end, de Bellaigue emphasizes the need to adopt multiple technologies to tackle the immense challenge of aviation emissions — highlighting hydrogen, electrofuels, and electric battery technologies as the most promising solutions. He concludes that, regardless of the chosen solutions, the environmentally-conscious pursuit of net-zero emissions is likely to make air travel far more expensive. 

iTunes Apple PodcastsGoogle PodcastsGoogle PodcastsRSS RSS

Full Text Transcript:

(As a service to our readers, we provide transcripts with our podcasts. We try to ensure that these transcripts do not include errors. However, due to a constraint of resources, we are not always able to proofread them as closely as we would like and hope that you will excuse any errors that slipped through.)

Jeff Schechtman: Welcome to the WhoWhatWhy podcast. I’m your host, Jeff Schechtman. One of the great ironies of the world today is that while the problems we face, particularly with respect to climate, must, if they’re ever to be solved, bring the world closer together in seeking solutions. One of the ways that we can come together via travel or in person is also one of the supreme carbon-intensive things that we do to harm the planet.

And yet, the airline industry has committed to at least making the effort towards zero emissions by 2050. Like so much of what must save us from the ravages of climate change, technology lies at the heart of the solution. Along with it, the forces of the market, of innovators, investors, entrepreneurs, and scientists, must move with the same vision that the Wright brothers took to create the idea of flying itself.

Telling this modern story is my guest, renowned British journalist Christopher de Bellaigue. Christopher de Bellaigue is a historian, a journalist, known for his reporting and books on the Middle East and environmental and ethical issues. He’s a frequent contributor to The Economist, The New York Review of Books, and The Guardian, and a recipient of the British Foreign Press Award. And it is my pleasure to welcome Christopher de Bellaigue here to the WhoWhatWhy podcast to talk about his newest work, Flying Green: On the Frontiers of a New Aviation. Christopher, thanks so much for joining us.

Christopher de Bellaigue: Thanks for having me, Jeff.

Jeff: Well, it is a delight to have you here. I want to first talk about whether or not there really is the desire to do something about greening aviation. We hear the airline industry, and you read about this in the book, the airline industry talking about it. How much of it is sincere? How much of this is real effort in your view?

Christopher: I can’t get into the head of the industry executives. I can’t get into the head of the CEOs of United Airlines and British Airways and Airbus and Boeing. However, what I can tell you is that there is increasing pressure on the industry, both from consumers and also from governments to do something about this very hard-to-abate sector.

It’s hard to abate because of very strong scientific and technical reasons, but it’s become harder to abate because the sector has been so late and so tardy in developing the technologies that are needed in order to get to that target of net zero, which I would remind you and your listeners is only an aspirational goal. It’s not enshrined in any law or treaty. It is merely an aspiration. And what we need to do as consumers is to hold the industry to account and to make sure that it strains every sinew in order to achieve that goal.

Jeff: Is much that’s happening with respect to technology happening because technology and investors and entrepreneurs are doing this to a certain extent on their own, knowing that it will find a reception within the airline industry, or how much is being driven by the industry itself?

Christopher: That’s a very good point. And the industry will, of course, point to areas in which, for example, airlines have invested in synthetic or sustainable aviation fuels. They’ve invested in plants that will one day produce gallons and gallons of biofuels that will enter the tanks. In the case of Airbus, for example, they have a project. They have a plan by 2035 to run regional routes by combusting hydrogen.

All of these things are being done by the industry, but my sense is that this is happening late, and it’s happening without enormous enthusiasm. What we need to do is look beyond the advertised or ostensible goal for the industry, which is to get to net zero by 2050, and see how much actual money they’re committing to this. If you look at sustainable aviation fuels, which is basically a marketing ploy, it covers everything from fuels that you create out of thin air to something that you will create from maize or from sugar, so it’s a vast gamut.

But if you look at the amount of sustainable aviation fuel that was consumed in the United States last year or produced and therefore consumed, it was 60 million gallons. Whereas the amount of non-sustainable ordinary kerosene, Jet A as it’s otherwise called that was consumed in 2019, which was a banner year for the industry, was 18 billion gallons. So we have an idea of just the enormity of the shortfall that needs to be made up.

Jeff: When we look at where technology is going, do we see potential tiers in this, that there may be an early stage that has to do with these biofuels, and that other things will come later?

Christopher: I think you’re absolutely right there. And I think the thing to identify in the early stage is different forms of sustainable aviation fuels. They can go into an existing airframe. As you know, when airlines buy an airplane, they don’t want to throw it away after 20 or 25 years. They want to use it for as much as possible. If possible, they want to sell it on when it gets a bit old.

And the advantage of sustainable aviation fuels is that they can go in. It’s a replacement fuel. It’s a top-up fuel. And, eventually, you will be able to fill your tank with it 100 percent. If you’ve flown out of LAX at any time in recent years, you will have been the recipient. You will have been the beneficiary of a very small amount of sustainable aviation fuel. So it is, in fact, being used at present.

Problem is that some of these fuels are not so green. And they have, themselves, a problematic carbon intensity. That is to say that they are producing greenhouse gases. Others, for example, creating fuel out of thin air. By that, I mean you draw carbon dioxide out of the air using direct air capture. And then you fuse it with hydrogen that is being created using an electrolyzer. And that produces a fuel that is a carbon, but it has exactly the same properties as Jet A kerosene that’s made from oil.

But provided it’s done using renewable energy, it’s carbon-neutral. Whether you’re following either of those routes, the question is whether you can produce the fuel in sufficient quantities, sufficiently quickly. So I think that biofuels as you suggest will be an early runner. In Europe, there’s more fuel being produced from waste and fats. And then we will start getting into the middle period of our transition, which will involve hydrogen. And hydrogen can be useful in an airplane in two ways.

It can be combusted as Airbus is hoping to do, or it can be used to power a fuel cell, which is a kind of reverse electrolyzer. And, essentially, you’re creating electricity by using hydrogen. And that can get you really quite a long way. Again, there is a problem because hydrogen, in order to be useful, you need to have a lot of renewable energy in order to produce it. And then you need to reconfigure the airports and the whole infrastructure around aviation needs to be reconfigured, which is a massive investment.

It involves not only the airlines, not only the airports but also government intervention as well. And then, finally, this is kind of holy grail, which everyone loves to talk about. And it’s, by far, the most glamorous of all these different routes to net-zero aviation, and that’s full electric. And that has problems of its own because, at present, we don’t have the battery power. Batteries simply aren’t powerful enough to carry large numbers of people for long distances through the sky.

Jeff: Talk about the reconfiguring of airports and what exactly would be required, why it would be such a monumental undertaking.

Christopher: Well, at present, what you generally happen with airports is that you have large quantities of Jet A air fuel being trucked in on tankers and then being stored on-site and then simply being poured into the machine. All of the preparatory work is being done off-site. Hydrogen is complicated because if it’s in liquid form, it needs to be stored at -235 degrees Celsius. So that requires quite a lot of preparation in itself. It can also be potentially extremely hazardous. So you can bring it in in liquid form or you could potentially bring it in in gaseous form.

When it’s up in the sky, you’ve got to re-gasify it if it’s in liquid form in order then to use it, either to combust it or to put it to use powering a fuel cell. All of these elements require quite a lot. If you’re going to, for example, bring it in in gaseous form and then you’re going to liquefy it on-site, that would require an enormous amount of energy and it’s been computed. But if you were to try and do that at Heathrow, it would require for small modular nuclear reactors to be working all the time in order to make that happen.

So with all of these different technologies, you have an enormous requirement of energy. And that energy has to be green energy. It has to be renewable energy. And that not only is difficult to achieve but also there’s a huge amount of competition for that green energy. And there are other sectors that are also clamoring for that green energy. And it’s arguable that some of those sectors are more important than aviation because aviation is, for the most part, a leisure activity. And how much do we allocate resource to a leisure activity as opposed to an activity that might seem much more intrinsic to our everyday lives?

Jeff: Talk about it in an everyday sense today. What if anything is being done to simply make the current system more energy-efficient and a little bit more green based on what we have now?

Christopher: Based on what we have now, there are different things that one can do. And, essentially, what the airlines have been doing is it’s useful, but it isn’t enough. What they’ve been doing is they’ve been improving fuel efficiency by something in the region of 1 percent a year for the last decade or two, but we think now that they probably reached the end of the road in terms of improving fuel efficiency.

There’s a new Rolls-Royce engine, for example, and the same is true of Pratt & Whitney and other engine manufacturers that are trying to have an exponential or a much more significant saving in energy and to pack much more power for the fuel that is put in, but they are in development. Essentially, what you’re doing is you’re running down the lifespan of the existing fleet before you get around to the much more difficult question of clean sheet technology, which is to say redesigning the airplane. So it actually looks rather different.

If you were going to redesign an airplane to carry hydrogen, you would have to take into account the fact that it’s much more voluminous. It takes up a lot more space than Jet A. And probably what you would do is you would store the hydrogen in the interstices of the wing or indeed in the fuselage. So you might have a much longer fuselage on an airplane, and the airplane might look rather different to the way it looks today.

The problem with clean sheet technology is the regulators get very involved, and also the airlines find it very, very costly because every single change needs to be signed off by the regulator. And then, of course, there’s the great fear, which is that safety will rear its ugly head and that you might end up in a position where you have a crash early on, which would, of course, set back that technology hugely because then the public would themselves start saying, “Well, do we want to get in a plane whose safety hasn’t been verified to the extent that we would like it to be?”

Jeff: How much of the problem comes from the fact that there are at least three legs to this stool and that there’s the airline industry, there’s the airplane manufacturers, and then the engine manufacturers?

Christopher: I tend to look at it as the industry as working really towards the same goal. I think that the way that the airplane is put together is that you have an airframe and then you go to an engine manufacturer and you say, “I’d like this engine to go in it,” but the actual driving force as I’m starting to discover — and it should be remembered, Jeff, that I came to this subject as someone who was interested in it. But as someone who’s very much an outsider, one of the interesting things that I’ve discovered is that driving motivation towards the greening of aviation or one of the key factors is the demand of customers.

And so, for example, the cargo and the freight industry are very keen to lower their carbon footprint. And what they will do is they will go to an airframe manufacturer and they will say, “This is what we require.” And then they will start the negotiations with the engine manufacturer as well. And the airlines are one very important part of the industry, but also the cargo industry is also extremely important. So, for example, DHL, for example, FedEx, Amazon are very much leading this effort to decarbonize the industry because they require that for their own carbon savings.

Jeff: Why is that? Why is the cargo industry more aggressive in this regard?

Christopher: It’s a very good question, and I’m not sure that I have a completely pre-prepared answer for you. I would imagine that the cargo industry is beholden to its customers and would like to present a much more green image. It may be that the cargo industry has intrinsically, within itself, a kind of green agenda that it wants to promote with greater sincerity than the airlines.

No one would accuse the airlines of being aggressively pro-green or pro-environmental in any shape or form. They’re being dragged picking and screaming into this process. That’s not to say that within the airlines, there aren’t extremely sincere reformers and reformists who will do all they can in order to advance this agenda, but the airlines, I wouldn’t say, are leading this. It’s more the cargo customers.

Jeff: Are there any individual leaders within the airline industry that have emerged in this quest?

Christopher: I’m very impressed by someone called Glenn Llewellyn, who is at Airbus, and he’s in charge of their green effort there. But it’s difficult for me as an outsider to ascertain how much power and how much investment the airlines are actually putting into their flagship green initiatives. Boeing, so far as I know, is not going towards hydrogen. Boeing, so far as I know, is much more interested in using SAF, sustainable aviation fuels, but I do think that the situation is evolving.

And I think that the position adopted by the airlines and by ICAO, which is the governing body of the aviation industry, has evolved significantly over the last five years from really not having a goal to then committing to at least an aspirational goal of going net zero by 2050. And then we will have to start to see whether there are measures that governments now need to implement in order to hold the industry’s feet to the fire and say, “You need to get there and, actually, you need to get there quicker.”

Because the industry built into the industry’s projections is the idea that they have until 2035 in order to get the different technologies lined up and developed, and then they will start cutting emissions. In fact, emissions need to stop. They need to be cut now. They need to be cut much, much quicker. And there’s one obvious route to cutting emissions, and that is to raise prices and to make people think much, much harder about whether they’re going to fly and to fly only when it really matters to them and when it’s much more important to them. That’s not something that the airlines would like to hear.

Jeff: One of the things that the airlines always has, you touched on this a few moments ago, that the airlines can always use to push back on is the issue of safety. That’s their ace card. Talk about that.

Christopher: Well, I think that’s right. And I’m not, again, within the airline industry, so I can’t say too much about the way that the airlines approach the question of safety other than, as you say, to double down on it as a reason for being much more cautious than they might otherwise be. I don’t necessarily blame the airlines entirely for that because I think that the consumer public is also very concerned about safety.

And in the US, the FAA, and the equivalent regulatory bodies in Europe and the UK, and elsewhere have the final say on any new design technologies that are going to get off the ground. So I wouldn’t necessarily ascribe cynical motives to this. I do think that, actually, in the past, we’ve seen occasions where safety lapses have happened and there have been appalling crashes. And I think that the paying public is also interested in safety. The paying public is also interested in price and has got used to the idea of flying incredibly cheaply. We are going to fly more expensively.

It is going to become more expensive to fly because of supply chain issues, because there’s less than an abundance of the workforce, the labor force that existed before the pandemic, and also fluctuations in the oil price. What we need to do is increase incentives and also increase taxes so that from both sides of the fiscal equation, the industry realizes that it’s in its best interest to invest more heavily both in time, but also in money in these technologies that would allow them, as you put it, to return to the spirit of the Wright brothers and to become really a force for good again in the world.

Jeff: There is a sense though that the entire industry and airports around the world and the infrastructure of those airports have really evolved and grown to the point where it is based on this idea of extensive and cheap travel. People basically taking planes as they might have taken buses years ago.

Christopher: I agree. This stems back to liberalization, which started in the US in the 1970s, then spread to Europe. And as emerging industrializing powers like India and China and Brazil and elsewhere, Indonesia have started flying in greater, greater numbers. Consumers there too are getting used to the idea of flying. They’re getting used to the idea of flying cheaply. It should be borne in mind that probably 80 percent of the world’s population have never been in an airplane.

And where aviation to develop into the mass activity that the industry would like it to develop into, then we’re going to have an even more serious problem on our hands. What we all need to be doing as individuals is flying less often. Of course, we need to be allowing those who haven’t flown before to enjoy the same privileges that we who do fly often enjoy. But at the same time, this isn’t an issue that we can fudge.

If you fly a transatlantic flight, for example, from Berlin to San Francisco and back again, you are producing more greenhouse gases than the average non-airborne citizen of Nigeria or India is doing in a year. And so there’s a massive imbalance here. There’s a massive climate injustice being perpetrated here. And we need to bear that in mind and we need to conduct ourselves and limit our flying accordingly.

Jeff: Talk about where in the world some of this cutting-edge technology is taking place with respect to some of the things you’ve touched on.

Christopher: Well, I think electric is very strong in where you are on the West Coast of the United States. EV tolls, electric vertical takeoff, and landing vehicles, that’s really one of the cradles of this emerging technology, which isn’t going to help the climate crisis very much unless it has an impetus towards further improvements in battery technology. So batteries can take you further and take more people further. But, actually, when you’re looking at electric, it really matters where your electricity is generated from.

Is it renewable? Is it green electricity or not? So that’s one of the things that one needs to consider. SAF or biofuels, again, the US is a world leader in that largely because so much of your ground transportation is run on biofuels. And I think what the aviation industry would like to do is as the ground transportation in the US and elsewhere switches over definitively and irrevocably to electric, then all of those enormous fields that are currently growing maize and other crops that get poured into the tank of automobiles in the US will be turned over and be used for airplanes.

Again, there’s a green credential problem here because you’ve got to farm those crops in a much more environmentally-friendly fashion in order for that to be a truly green solution. Then you’ve got something called electro fuels, which involves sucking carbon dioxide out of the air and then fusing it with hydrogen, which is being created using an electrolyzer. And that is much stronger in Europe.

There’s technologies that I’ve visited in Dresden and also in Switzerland, which are going to combine using thermal energy created in Norway, that a plant is now being built that will produce electro fuels. Hydrogen, that is also happening. For example, I visited a company called ZeroAvia in the UK, which is repurposing existing small airplanes, Cessnas and Dorniers, and that kind of thing. And that will be powering a fuel cell.

They think that they can get to 70 seaters within five years’ time. And that would be extremely interesting and that would make them pretty much an industry leader if they manage to do that. And then as I mentioned earlier, Airbus are also doing hydrogen, only this time through the combustion route. And there are other technologies that are much earlier in development.

Some people are talking about, how would you power an airplane using nuclear fuel and all sorts of other biofuels that are still in development? So one of the interesting things about this subject is that one doesn’t really know exactly who’s going to win the race. And to an extent it, it is a race. And yet from my perspective, they’ve all got to win because there is such a large amount of aviation. And none of these technologies on its own is going to be able to carry the burden.

Jeff: To what extent is nuclear a realistic possibility?

Christopher: I don’t know because I didn’t look closely into nuclear because I was told that we are a very, very long way from being able to square that with any kind of safety concerns, let alone the technological challenges that that would pose. So I didn’t actually look very closely into nuclear. I don’t think it’ll happen for a long time. And I think that essential question of safety will loom very large. There are entrepreneurs who are looking into the question, who are trying to develop it. In fact, people have been talking about nuclear-powered airplanes way back since the beginning of the Cold War. But whether that’ll happen on a commercial scale, I don’t know.

Jeff: Of all of the things that you saw that were being worked on, which ones did you think were the most exciting but also the most practical, the ones that really had a chance to make an immediate difference?

Christopher: I would say that hydrogen has a good chance in the medium term. It’s abundant. Its green credentials are pretty good. If you put it into a fuel cell, all you’re doing is producing contrails. That’s the only kind of noxious emission that takes place. If you burn it, then you do get nitrous oxide. But at the same time, you’re drawing it from water. So its production shouldn’t involve any emissions.

It does need a lot of energy. And I think this is where all of the technologies have really questions to answer is how you assure yourself of renewable energy that isn’t more badly needed by other more vital sectors of the economy. I do think hydrogen has a very positive future. I like to think that electro fuels have a positive future because they are incredibly exciting.

The idea that you can create a fuel literally out of thin air and water is remarkable to me. Again, a lot of renewable energy required. And then in the next 50, 60, 70 years, if you can develop battery technology to the extent that you can carry large numbers of people over long distances, then, obviously, full electric is amazing because then you’re not emitting anything at all.

Jeff: And, finally, do you sense that there is any kind of clamoring for this among the flying public? To what extent is the flying public aware of this and sensitive to this? Do you have a sense of that?

Christopher: I think the flying public is starting to become more sensitive to this. I think they’re starting to realize that each time they get into an airplane; they’re contributing enormously to the climate problem. Having said that, it’s a microcosm of the choice that everyone, all of us, we all make every day of our lives. Whatever we do on this planet is that it’s the immediate needs and it’s the moral conundrum that we all face every day.

So I’m definitely not in a position where I sit in judgment on anyone at all, but I do think that people are starting to become more aware of it. And I hope that in time, that will drive a change in behavior, a change in conduct, but also a much more critical view on the part of the paying public with respect to the airline industry, with respect to the aviation industry in general. The aviation industry has been cosseted and it has been privileged for a very long time.

It pays negligible taxes. The airlines do not pay tax on jet fuel. There’s no tax levied on international air tickets. If you look at the number of years in the past 20 when the airlines have paid corporation tax, you’ll be surprised by how few they’ve paid corporation tax. It’s a largely untaxed industry that has got away with being very late to the party or the decarbonization party and is now arriving late in the day. And it needs to perform, needs to up its game.

Jeff: Christopher de Bellaigue. The book is Flying Green: On the Frontiers of New Aviation, just out from Columbia Global Reports. Christopher, I thank you so much for spending time with us today here on the WhoWhatWhy podcast.

Christopher: Thanks a lot, Jeff.

Jeff: Thank you. And thank you for listening and joining us here on the WhoWhatWhy podcast. I hope you join us next week for another radio WhoWhatWhy podcast. I’m Jeff Schechtman. If you liked this podcast, please feel free to share and help others find it by rating and reviewing it on iTunes. You can also support this podcast and all the work we do by going to


  • Jeff Schechtman

    Jeff Schechtman’s career spans movies, radio stations and podcasts. After spending twenty-five years in the motion picture industry as a producer and executive, he immersed himself in journalism, radio, and more recently the world of podcasts. To date he has conducted over ten-thousand interviews with authors, journalists, and thought leaders. Since March of 2015, he has conducted over 315 podcasts for

    View all posts

Comments are closed.