IT IS a bad time to be working in aviation. The past year has seen Greta Thunberg travel the world while shunning planes, climate protesters occupying airports and the Flygskam (flight shame) movement on the rise.
The aviation industry has been under pressure to cut its climate change impact for some time, but the pressure is growing. At a meeting near Geneva airport in Switzerland last month, the International Air Transport Association (IATA) warned that, without faster action on emissions, the industry faces a shift in public attitudes and countries unilaterally imposing environmental taxes.
France has already put a modest on outward-bound flights beginning this month, and Sweden imposed one last April. Even the UK, the , saw election battle. Environment pressures don’t yet pose an existential threat to the industry, but it is anxious.
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The problem isn’t so much current aviation emissions, even though at between 2 and 3 per cent of the global figure they account for more emissions than the whole of Germany. The real issue is the rate of growth. China and India’s flight numbers are increasing 10 per cent a year. Global aviation CO2 emissions have climbed 27 per cent in the past five years, to (see “Aviation emissions marched upwards again in 2019”).
There are signs that Greta and Flygskam are having an impact. Emissions from flights in Sweden – a proxy for flight numbers – fell in the first half of 2019. Alexandre de Juniac, CEO of the IATA, rejects the idea that Flygskam is solely to blame, arguing that it isn’t possible to tease out its effects from those of Sweden’s aviation tax and weak economic growth.
However, figures from the Netherlands show the same trend, and recent numbers reveal that , while rail trips were up.
Faced with these headwinds, aviation is turning to technology and carbon offsetting (see “No silver bullet”) to clean up its act – and ward off more regulation.
The industry thinks biofuels will be a big part of the answer. The IATA prefers the term sustainable aviation fuel: biofuels that don’t compete with food production. Such fuels can cut emissions by 70 or 80 per cent when raw versus fossil fuel-based kerosene, with which they are blended.
Some of these fuels are made from waste animal fat and used cooking oil but others contain controversial materials, such as palm oil, which is linked to deforestation. Henrik Erämetsä at Neste, which makes biofuel for European and US airlines, says they don’t use palm oil because customers don’t want it. But attitudes differ globally. The chief executive of AirAsia recently said the airline is a ” big supporter for palm oil”.
“Without faster action on emissions, the aviation industry faces a shift in public attitude”
Even if greener fuels can avoid environmental side effects, they still face two big problems. The first is scale. About 220,000 flights have used the fuels since 2008, which sounds like a lot until you consider that there were 39 million flights in 2019. Biofuel accounts for just 0.01 per cent of all aviation fuel used today. The IATA says the share could rise to 2 per cent by 2025, but only if governments provide incentives.
Price is the other hurdle. Biofuels typically cost three times the price of fossil fuels. Asked when greener alternatives will reach price parity with kerosene-based jet fuel, Erämetsä is blunt. “The short answer is never. We just have to appreciate the fact the renewable fuels are more expensive.”
What about embracing electrification instead, as car manufacturers are rapidly doing? The only electric planes in development today are a long way from commercial jumbo jets. Models such as the Alice by Israeli start-up Eviation will carry nine passengers. Rolls Royce hopes its ACCEL model will set the speed record for an all-electric plane in the first half of the year; it has a single seat. The firm is one of a group working to certify an electrified version of a nine-seater Britten-Norman plane by 2022.
The reason companies are starting small is simple: weight. The kerosene jet fuel powering the gas turbine engines on today’s planes is much more energy dense than batteries, says Duncan Walker at Loughborough University, UK. Kerosene holds around 42 megajoules per kilogram compared with at most 1 megajoule per kilogram for a lithium-ion battery. And unlike batteries, as fuel is burned during the flight, the weight decreases, boosting efficiency.
Electrifying small planes will do little to reduce aviation’s CO2 emissions, says Walker, but he thinks they are a legitimate stepping stone for testing the technology. Richard Goodhead at Rolls Royce sees promise in electrification at all scales, but says it will be difficult. “The bigger the aircraft is, and the longer it flies, the more challenging it is to use a purely electric solution,” he says.
A key test for electrified planes will take place in 2021, when Airbus hopes to fly the E-Fan X, a plane the size of a regional airliner, with one of the engines swapped out for an electric motor, albeit powered by a gas turbine in the plane’s fuselage. It will allow the firm to test voltages much higher than normal in planes, to keep electricity losses to a minimum. The low pressure and high altitude environment of a plane mean high voltages pose technical challenges, including higher temperatures and electric discharge.
With today’s technology, a pure electric plane would have no space for passengers, says Sandra Bour Schaeffer at Airbus, because the batteries would take up the entire structure. But she says the firm will have a fully “decarbonised plane” ready by about 2035, which could involve other technologies, potentially even hydrogen.
Realistically, hybrid electric and fully electric planes are about 40 years away, says Walker. This is partly because the safety-focused production cycles of the big plane makers mean it takes some 20 years for the likes of Airbus and Boeing to produce a new model.
There are other ways aviation can cut emissions. But they are either incremental – more efficient engines, better management of air traffic and ways to cut fuel during take-off – or unlikely to happen for reasons of cost, such as advanced planes that look radically different from today’s fixed wing designs.
The industry may want to get less heat for its climate change impact but the technology just isn’t mature enough to fix its footprint any time soon. Quick, deep cuts in carbon emissions only look likely to come from people following Greta’s example and the industry accepting slower growth. During three and half hours of debate in Geneva, that idea was never aired.
No silver bullet
Starting this month, airlines will have to offset any growth in their carbon emissions, although not their existing, sizeable emissions. It is part of a . The industry says airlines will fund reforestation and clean energy projects worth about $40 billion over the next decade.
Kai Landwehr at Swiss offsetting group MyClimate says carbon offsetting isn’t a silver bullet for the aviation industry. “But it is a proven and impactful and measurable system. It buys us time before we are ready to decarbonise.”
Some airlines are also choosing to offset passengers’ flights for them. British Airways has started offsetting all domestic flights this year. Easyjet recently began offsetting all its flights.
Landwehr calls Easyjet’s move bold, saying its cheap offsets, which cost just £3 per tonne of carbon dioxide, may not guarantee the money goes to new projects, which is crucial for real offsetting.
“We have a rigorous process to select the schemes we buy credits from,” says an Easyjet spokesperson. “These accreditors check projects to ensure the carbon reductions they are claiming would not have happened without the offsets.”
