Flights of fancy?

A Virgin Atlantic Boeing 787-9 Dreamliner. On 28th November 2023 one such aircraft became the first to complete a long-haul flight powered exclusively by sustainable aviation fuel

A Virgin Atlantic Boeing 787-9 Dreamliner. On 28th November 2023 one such aircraft became the first to complete a long-haul flight powered exclusively by sustainable aviation fuel

In the tinderbox summer of 1984, the notorious Battle of Orgreave saw 8,000 pickets and 5,000 police converge at a coking plant on the eastern fringes of Sheffield. The miners were protesting prime minister Margaret Thatcher’s plan to modernise and deregulate the coal industry, fearful that it would lead to mass closures. The violence that ensued was the bloody dénouement to the miners’ strike, and the housing estate that now sits on the former battlefield is a brutally anodyne reminder of which side ultimately prevailed.

Forty years on, and just a few hundred yards away, another high-stakes battle is being waged, with fossil fuels once again at the centre: the decarbonisation of global aviation. This is the site of Sheffield University’s Energy Institute, where organisation head Professor Mohamed Pourkashanian and his team are at the vanguard of the embryonic Sustainable Aviation Fuel (SAF) sector.

The broadest of umbrella terms, SAF encompasses all types of alternative aviation fuel made from non-fossil ‘feedstocks’ (raw materials). These might include cooking oils, plant sugars, forestry residue, even human excrement. Chemically similar to, and visually indistinguishable from, conventional jet fuel, they create a fraction of the carbon footprint.

There isn’t enough cooking oil in the world to power more than one day’s aviation” – Michael O’Leary, CEO of Ryanair

The Energy Institute’s mission is as daunting as it is critical: to develop, test, regulate and enable the rapid upscaling of SAFs in the hope that they can break traditional jet fuel’s environmentally destructive hegemony and drive the trillion-dollar aviation industry towards its target of net zero by 2050. The quest received a significant PR boost on 28th November 2023 when Virgin Atlantic’s #Flight100 – the first long-haul flight to be 100 percent powered by sustainable fuel – travelled from London to New York. “It was fantastic,” says Pourkashanian, who was one of the small number of scientists, politicians and journalists invited on board. “It felt like any other flight, only the fuel it used would have produced 70 percent lower CO2 emissions over its life cycle. But I believe we can go much further than that.”

Professor Mohamed Pourkashanian, head of the University of Sheffield’s Energy Institute, was awarded an OBE in 2023 for his pioneering work around aviation decarbonisation

It was a great proof of concept, he says, demonstrating that a plane can be safely flown entirely on sustainable fuel. Efficiently, too; one of the big selling points of SAF is that it is “drop-in”, meaning it can be blended in any concentration with traditional jet kerosene and doesn’t require modifications to aircraft or refuelling infrastructure.

Shai Weiss, chief executive of Virgin Atlantic, described #Flight100 as “momentous”. Michael O’Leary, CEO of Europe’s biggest low-cost airline Ryanair, wasn’t so sure. The pioneering fight was powered by so-called biofuels, the most developed branch of SAF, in this case derived largely from waste fats. This feedstock, argued O’Leary, is vanishingly scarce when measured against the insatiable thirst of global aviation.

“I don’t see where we will get the supply in the volumes we need,” he railed, in a characteristically forthright interview with the Guardian. “You want everybody running around collecting fucking cooking oil? There isn’t enough cooking oil in the world to power more than one day’s aviation.” Pourkashanian – calm, analytical, with the measured, reassuring tone of an airline captain – smiles when I put this to him. “The thing is, he’s not wrong,” he says. “But it’s a red herring because that is only one way of producing sustainable aviation fuel.”

The branch of SAF most likely to deliver aviation into the elusive embrace of net zero, says Pourkashanian, is Power to Liquid (PtL). So great is its potential that it could meet the needs of the entire UK aviation industry by 2030, he believes – far exceeding the incremental SAF targets that are being adopted across the industry.

PtL sees hydrogen, extracted from water using renewable energy, blended with carbon taken from industry or the atmosphere. A chemical process known as the Fischer-Tropsch reaction (FT) combines the feedstocks to produce a synthetic kerosene that delivers a minimum of 90 percent less CO2 in lifecycle terms. The carbon double win – both vastly reducing emissions and hoovering them up – is what has got everyone excited; loosely analogous to an electric car that draws its power directly from the exhaust of your chugging family diesel.

During a hard-hat tour of the Energy Institute’s shinily inscrutable buildings I get to see each step of this remarkable alchemy in isolation. Pourkashanian and his team are based in the Lego-block Translational Energy Research Centre (TERC), officially opened in January 2024. Next door is the larger Sustainable Aviation Fuels Innovation Centre (SAF-IC), the UK’s first clearing house for the testing and certifying of new SAFs. Out front, workers in high-vis are battling heavy winds as they lay the foundations for the £80m, Boeing-partnered Composites at Speed and Scale (COMPASS) facility. Clearly, you’re nothing in sustainable aviation without a snappy acronym.

Guided by Ihab Ahmed, a research associate at TERC, I’m shown the site’s two electrolysers, powered by solar panels on the roof, which decouple the hydrogen from the water. In the yard outside are a variety of carbon-capture units: one as tall as a three-storey building with pipes and tubes aligned vertically like a cathedral organ; another stouter with a “rotating packbed” like an oversized tumble drier. And, finally, the “FT plant”, whose waxy liquid product is refined into PtL.

The process is nothing short of miraculous – but little more than hobby vineyard in scale. “This is a new market with no supply chain so it means everything is built unit by unit currently which is expensive,” says Ahmed. “We need to give confidence to investors to show ‘look, this works’. Then investment will follow.” Such awareness is key to unlocking SAF’s economies of scale – and it’s undoubtedly growing.

Pourkashanian tells me a story of chatting to a septuagenarian in his home just before Christmas 2023. The man had recently returned from a trip to Kenya and while he was encouraged that his airline was using 50 percent sustainable fuel on the outbound flight, it required conventional jet fuel for the return leg because there was no commensurate production in east Africa. “He was very informed and enthusiastic about the potential of these fuels,” the professor tells me.

The home was Buckingham Palace and the man – dispensing an OBE to Pourkashanian for services to net zero research and innovation – was the king.

Commercial aviation has become so entrenched in our daily lives that it’s easy to forget just how fledgling an industry it is. A century ago, it was little more than an elitist pursuit. This year, a record 40.1 million flights are expected to operate, or 4,566 every hour, according to the International Air Transport Association – double the figure at the turn of the millennium. On this nosebleed-steep trajectory, the tumbleweed skies of the pandemic register as just an anomalous blip.

The exponential increase has seen a concomitant rise in CO2 emissions: 32.6 billion tonnes since the dawn of commercial aviation, according to a study in 2018 – approximately half of which has been emitted in the last 20 years. And that, in more than one sense, is just the warm-up: international airline body IATA is projecting a fivefold increase in annual passengers, from just over two billion a year in 2021 to ten billion by 2050.

Unchecked, such meteoric growth would see aviation become one of the largest emitting sectors in the coming decades – with devastating consequences for attempts to keep global temperature rises within 1.5-2°C of pre-industrial levels, as defined by the Paris Agreement set at the COP21 UN climate change conference in 2015.

There are levers to pull. Analysis by global consultancy firm McKinsey estimates that through improved engines, materials and aerodynamics, each new generation of aircraft is up to 20 percent more fuel efficient than the last. Realigning flight paths and better use of airspace to cut down on holding patterns and enable aircraft to burn less fuel is another – in relative terms – easy win.

Meanwhile alternative propulsion technology such as electric and hydrogen is advancing all the time, powered by innovative pilot projects. But all these options – as well as the sticking-plaster solution of carbon offsetting – collectively constitute a mere tinkering around the edges. View any pathway-to-decarbonisation pie chart and the largest slice – two-thirds in the case of IATA’s Fly Net Zero strategy – is marked with those three speculative initials: SAF.

The result has been a raft of sustainable fuel commitments. The UK government, via its Jet Zero campaign, is targeting ten percent of all jet fuel supply to be produced from SAF by 2030. IAG, parent company of British Airways, has set the same benchmark, along with Air France-KLM. Notwithstanding O’Leary’s cooking oil rant, Ryanair has opted for a target of 12.5 percent green fuel by 2030. The EU, meanwhile, favours a staggered approach: two percent usage by next year; rising in increments to 70 percent in 2050. The mandate, voted for in the European Parliament in September 2023, is awaiting ratification by EU member states. Across the Atlantic, the US is focusing on accelerating production rather than setting goals for consumption, with the Biden administration offering generous incentives to green-fuel producers.

The opportunities are enormous… I like to think of it as excremental growth” – James Hygate, Founder, Firefly Green Fuels

No country is under any illusions: the challenge of scaling up SAF is little less than stupefying. IATA estimates that 450 billion litres a year will be needed by 2050 if sustainable fuel is to supplant traditional kerosene. Best-case projections for global output this year are 1.875 billion litres. Then there’s the increased cost. “At today’s prices, SAF is on average three to five times more expensive than traditional fossil fuels,” bemoaned Julia Simpson, president and CEO of the World Travel & Tourism Council (WTTC) at a conference in Abu Dhabi in May 2023. Without significant financial support and incentives from government, she said, decarbonisation of the sector would be impossible.

Finally, perhaps most problematically, there’s the feedstock availability issue. Echoing the sentiment if not the colourful language of O’Leary, the Royal Society published a report in early 2023 warning that to meet even existing UK aviation demand through biofuels would require commandeering half of the country’s agricultural land. As for Pourkashanian’s white knight, PtL, producing sufficient green hydrogen for zero-carbon aviation would take 3.4 times the UK’s 2020 wind and solar energy output – and at a time of increasing competition for renewable energy from other sectors also pursuing net zero targets.

What’s needed, clearly, is a feedstock that’s ubiquitous, inexhaustible and dirt cheap. Too much to ask? At a green energy start-up a three-hour drive from Sheffield’s blustery eastern fringes, they certainly don’t think so.

It’s a drizzly January morning in the West Country and James Hygate is feeling under the weather. The 47-year-old, a former zoology student and one of the UK’s foremost experts in biofuels, is battling through, nonetheless. Rest is for wimps. He has, in every sense, got shit to do.

Crude oil created from human waste is poured into a cylinder at the Firefly Green Fuels facility in Gloucestershire. The liquid can be processed into aviation fuel which has a 90 percent lower carbon footprint than fossil fuels

Hygate’s company, Firefly Green Fuels, has pioneered a process for turning one of the most unloved and prevalent products in the world into sustainable aviation fuel: sewage. The process Firefly has developed in its laboratories on the banks of the Severn in south Gloucestershire begins with so-called biosolids, the end product of the waste-water treatment system. “It’s actually relatively inoffensive,” says Hygate when I speak to him at head office, in a red-brick former parcel-sorting depot beside Bristol’s Temple Meads station. “It looks like manure and is very nutrient rich.”

Using hydrothermal liquefaction (HTL) – a combination of high pressure and heat – a thick, gloopy crude oil, rich in hydrocarbons, is harvested from the sewage sludge and then processed into sustainable fuel. Independent aviation regulators and specialists from Cranfield University, in Bedfordshire, found the product was chemically nearly identical to standard fossil jet fuel and had a 90 percent lower carbon footprint.

Hygate, who started out on a farm in  rural Gloucestershire 20 years ago turning rapeseed oil into biodiesel and says he is motivated by a desire for his children not to grow up in the midst of a climate emergency, believes his sewage-to-SAF could revolutionise aviation.

None has yet been tested in flight – it must first pass through Sheffield University’s clearing house. But some airlines have already seen enough. Wizz Air, one of Europe’s fastest-growing low-cost carriers, has signed an ‘off-take agreement’ (a binding pledge) to take 525,000 tonnes from Firefly over 15 years from 2028 once its first plant comes on stream. “That’s nearly a billion dollars worth of fuel,” says Hygate, enthusiastically. It’s the abundance of feedstock and resulting global scalability that excites him most. “The opportunities in big cities particularly are enormous,” he says, adding with a smile: “I like to think of it as excremental growth.”

Also ubiquitous, and slightly easier on the nose, is sunlight. Swiss, part of the Lufthansa Group – the biggest player in Europe’s aviation industry – has teamed up with compatriot clean-tech company Synhelion to develop a form of sustainable aviation fuel called Sun to Liquid (StL). The process involves light from the sun being concentrated through a field of mirrors to reach temperatures of up to 1,500C. This in turn drives a thermochemical reaction that converts water – alongside carbon taken from industrial sources or removed from the air – into a synthetic liquid kerosene.

According to calculations made by public research university ETH Zürich, a solar-power production facility a third the size of California’s Mojave Desert could cater for the entire global aviation sector’s kerosene requirements. “Solar heat is the most cost-effective renewable energy source, it’s available in vast quantities and it’s usable in many locations all over the world,” says Melanie Heiniger, head of corporate responsibility at Swiss, which plans to be the first airline to trial solar fuel.

The wider Lufthansa Group offers passengers the option of offsetting emissions by purchasing SAF to be used on one of its future flights. And if that sounds like paying for a taxi and then being invited to pick up part of the tab at the petrol station en route, that’s because, well, it is. Take-up is currently around three percent of customers.

Is this the future, then: passengers paying for airlines to clean up their act? “The transformation of our industry into a provider of more sustainable air travel entails substantial costs and investments,” accepts Heiniger. “We’re pretty firmly convinced that, ultimately, we’ll have to pass on at least part of these costs to the customer.”

Quite right, says David Lee, a professor of atmospheric science at Manchester Metropolitan University who has spent 25 years studying the effects of aviation on climate change. “Personally I think flying is too cheap for the environmental cost.” He laments the catastrophic prevarication over the past three decades in addressing aviation pollution. Lee recalls penning IPCC [Intergovernmental Panel on Climate Change] reports back in the late 1990s warning of the devastating effects of both aviation’s CO2, and non-CO2, emissions – the latter comprising nitrogen oxide, aerosol gases and contrail cirrus clouds that linger at high altitude and serve to trap escaping heat.

“The irony about the growth of aviation is that half of the cumulative emissions have happened since 1999. We knew how serious it was then and, since, we’ve seen astonishing growth. It’s like we’ve been sleepwalking.”

More sustainable air travel entails substantial costs. We’ll have to pass on at least part of these to the customer” – Melanie Heiniger, Swiss Air Lines

The one thing that could massively reduce aviation emissions at a stroke, of course, is the only thing not on the table: dampening demand. The projected five-fold increase in passenger numbers is being treated as a fait accompli – in some ways akin to an alcoholic deciding that, instead of seeking help, they’re going to pack their home with all the booze they can find and simply devote their energy to removing the trip hazards.

One reason for this, says Dr Doug Parr, policy director for Greenpeace UK, is industry lobbying. He says that comments made by Labour minister Chris Mullin 20 years ago ring just as true today. “During my 18 months as a minister whose responsibilities included aviation, I learned two things,” Mullin wrote at the time. “First, that the demands of the aviation industry are insatiable. Second, that successive governments have usually given way to them.”

For Parr, it’s the blind faith being put in sustainable fuels that are unproven at scale that makes him most uneasy. He paints a picture of a Ponzi scheme of pledges, projections and press releases, with scant firm evidence that SAFs can actually meet the burden they’re being asked to shoulder.

The only tangible thing, he says, are the torrents of emissions being pumped into our atmosphere by aviation on a minute by minute basis. In the seven hours it took Virgin’s Boeing 787-9 Dreamliner to make its smooth, cooking oil-lubricated progress from London to New York City in November, more than 30,000 other flights would have taken to the skies – only a fraction of them running on a tiny proportion of sustainable fuel.

“Sustainable aviation fuels can be low carbon, potentially even zero carbon, but they barely exist and we don’t know at what cost or to what extent they will be able to fulfil what the aviation industry is seeking,” says Parr. “To my mind it’s a highly risky strategy to imply, or embed in policy as we are doing in the UK, that we can expand aviation based on something that’s untried, untested and unverified.” Without measures to actively constrain demand, he says, pursuing such a strategy is nothing short of “reckless”.

Demand constraint will never happen, says Guy Gratton, associate professor of aviation and the environment at Cranfield University. Two reasons: the tens of millions of emerging middle class people in countries such as China and India understandably eager to enjoy the same travel privileges their western contemporaries have been savouring for decades. And the global economy’s unhealthy economic dependence on an ever-increasing number of us taking to the skies. This year alone, the sector is expected to generate nearly a trillion dollars in revenue, according to the International Air Transport Association.

Virgin Atlantic crew members flank Sir Richard Branson, UK transport secretary Mark Harper and the airline’s CEO, Shai Weiss, after the arrival of #Flight100 into New York

“Whole industries and millions of people, probably billions – many of whom will never actively fly themselves – are doing things that rely upon aviation,” says Gratton. “So if you follow the fly-less, heavy demand-control narrative you are essentially promoting a massive downgrading of the world’s economy. I can’t see any government supporting that.”

Perhaps the biggest obstacle to the smooth acceleration to decarbonisation is one the EU could find itself up against as it moves to ratify its ambitious pledges: good old-fashioned politics. If the 28 COP climate change conferences thus far have proved one thing, it’s the difficulty of plucking the fruit of unanimously-agreed and binding resolutions from the thickets of self-interest.

Just a few days before the #Virgin100 flight took off last year, more than 100 countries came together in Dubai under the guise of the International Civil Aviation Organisation (ICAO) to agree interim goals for emissions from global aviation by 2030. After five days of talks, a target of five percent lower carbon emissions emerged. An earlier draft had a goal of five to eight percent. China, which has only consented to targeting carbon neutrality by 2060 rather than 2050, said the ambition would “enormously increase” airline operating costs and discriminate against developing countries. Saudi Arabia and Iraq, two significant oil producers, voiced dissent at both the target and the date.

Then there’s the issue of how to ensure a level playing field among competing airlines: some, subject to pricey SAF mandates; others (likely in the developing world), with a healthy antipathy to the idea of footing the environmental bill for decades of unfettered aviation among developed nations.

Back in Sheffield, Professor Pourkashanian’s optimism remains undimmed. Over coffee in TERC’s expansive boardroom following my site tour, he talks of companies and investors banging down his door for information on the so-called ‘fuels of the future’; the rapid recent scaling up of SAF production globally (a projected 300 percent rise, year on year, in 2024); and the supplementary prize of greater energy security.

The economic bounty provided by the switch to green fuels should also not be overlooked, he says: a silver lining, if you will, to all those contrail cirrus clouds scarring the troposphere. In December 2023 Reuters reported that as much as $3.2 trillion of SAF capital development may be needed to achieve the sector’s net zero emissions goal, with 14 million jobs created or sustained by the transformation. And whereas the vast majority of fossil-derived kerosene comes from just 22 countries today, SAF could create opportunities in almost every country.

But if passenger numbers do go on ballooning and sustainable aviation fuel doesn’t prove to be the saviour that everyone’s betting the farm on, that’s going to be ecologically calamitous, I say – because by then it’ll be too late to alter course. “I don’t think governments and international organisations like COP will allow that to happen,” Pourkashanian responds, evenly. “Every day we’re seeing the impact on the environment more and more. At some point everybody has to take it seriously. Real decisions have to be made and implemented.”

One doesn’t have to search far to find those who don’t share his optimism. From a marketing and profile perspective, Carbon Independent is the antithesis of Virgin Atlantic and its slick #Virgin100 PR campaign.

Net zero 2050is laughable… It’s ludicrous. The figures don’t add up” – Dr Ian Campbell, Founder, Carbon Independent

The basic, not-for-profit website is buried multiple pages deep on Google and is devoid of images or design flourishes. It’s source and data heavy. And it’s objectively, dispassionately terrifying. In meticulous detail, the site sets out the remaining carbon budget, country by country, if global warming is to be kept within a 1.5C rise by 2050. The UK’s share, calculated by population size, runs out in two years. At current emission levels, the global CO2 budget will be exhausted in just seven. By which time the UK, for all its pledges and enthusiastic espousing of SAF, will still be permitting its aviation sector to be 90 percent powered by fossil fuels.

I track down and call Carbon Independent’s creator and editor, Dr Ian Campbell, a former medical statistician who felt compelled to set up the site in 2007 to give unbiased and transparent information about the looming climate emergency. I apologise for catching him at the weekend. “No problem. This subject is far more important than my social life,” he responds, flatly.

Campbell is scathing about what he sees as the belated, tokenistic moves towards aviation decarbonisation. “Immediate and radical” action is needed, not experimental and incremental, he says. And he’s worried that ventures such as #Flight100 will merely convince the travelling public that we’re on a smooth cruise towards guilt-free, emissions-free air travel and that behaviour therefore doesn’t need to be moderated.  “[Net zero] 2050 is laughable,” says Campbell. “It’s ludicrous. The figures don’t add up. If they [the aviation industry] were pressed to explain the pathway and the emissions in detail, it would be fascinating to see what they come up with. The biggest problems are groupthink and denial. That and the fact that we should have started this at least 30 years ago.”

Posted on Friday, June 21st, 2024 - Categories: #53 - Oct-Dec 2023, App Issues.