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Aviation is plotting a sustainable course

In the climate world, aviation is referred to as a hard-to-abate sector, but it's pushing to do better.

Plane on runway

This article originally appeared in the State of Green Business 2021. You can download the entire report here.

Modern aviation had never seen a year like 2020. The COVID-19 pandemic led to a near-total halt in air travel, with airlines hemorrhaging billions of dollars and shedding hundreds of thousands of jobs. It wasn’t just that the economy was in a holding pattern. People also didn’t want to spend hours inside a closed container with scores of their fellow humans. Add to that the rise of virtual meetings and sales calls, and suddenly there were far fewer reasons to go to an airport.

That forced grounding provided airlines with a reckoning — and an opportunity for a reset. And it begs the question: Can sustainable aviation finally get off the ground?

The answer is yes. But like modern planes themselves, a lot of moving parts are involved. In the climate world, aviation is referred to as a hard-to-abate sector, alongside other heavy industries — shipping, aluminum, cement and concrete, among others — that aren’t easy to decarbonize through redesign or electrification. Regardless, pressure has been on aviation to join other sectors in dramatically cutting greenhouse gas emissions.

The industry has responded or at least has been pushed to do better. In 2016, the International Civil Aviation Organization (ICAO), a U.N. body, set a course for airlines to offset emissions of international flights above a 2019-20 baseline. In other words, aviation emissions wouldn’t grow beyond the baseline, even as air travel increased.

The pandemic led ICAO to scale back the program, CORSIA (for Carbon Offsetting and Reduction Scheme for International Aviation), to make it easier for airlines to comply.

The sooner that the costs of carbon control are included in the costs of doing business, the sooner new technologies will be developed.

That may have been shortsighted. Research has found that robust implementation of CORSIA could significantly reduce aviation’s climate impact, and that aviation’s contribution to future warming could be cut by roughly 90 percent if the sector aggressively pursued decarbonization.

"As airlines scramble to recover from the COVID-19 crisis, they can’t afford to ignore the looming global crisis of climate change," said Annie Petsonk, an aviation expert at the Environmental Defense Fund. "Real leadership means setting the aviation sector on a path toward net-zero climate impacts as swiftly as possible. The sooner that the costs of carbon control are included in the costs of doing business, the sooner new technologies will be developed." 

Three things can be done to reduce aviation’s climate impact. Some measures, such as fuel efficiency, go straight to airlines’ bottom line. Fuel costs account for about 24 percent of operating expenses, according to the International Air Transport Association. Anything airlines can do to cut that — through improved taxiing or takeoff and landing practices, for example — saves both costs and emissions.

The heavier lift comes from sustainable aviation fuel — SAF, for short — which can be made from a variety of substances, including used fats and oil as well as agricultural waste. A so-called "drop-in fuel," it can directly substitute for Jet A-1, the fuel most commonly used globally in jet engines, although most jets can accommodate mixes that include no more than about 50 percent SAF. To date, SAF is expensive — several times the price of Jet A-1 — and its availability is extremely limited.

Still, airlines are fueling up where they can — notably, at California airports, thanks to a Low-Carbon Fuel Standard designed to decrease the carbon intensity of the Golden State’s transportation, and in Europe, where governments are poised this year to mandate the growth of SAF. At airports in San Francisco and Frankfurt, for example, some planes already fuel up with a blend that includes a tiny amount of SAF — less than 1 percent, almost literally a drop in the bucket.

That drop could grow considerably. A bill introduced in the U.S. Congress in November aims to set a national goal for SAF to enable the U.S. aviation sector to achieve a 35 percent reduction in carbon emissions by 2035 and net zero emissions by 2050.

Policy already is playing a key role elsewhere. Norway has mandated that 30 percent of aviation fuel in the country must be sustainable by 2030 and that all short-haul flights be 100 percent electric by 2040. Canada implemented a carbon tax on domestic flights, based on the amount of fuel used. Germany has raised taxes on intra-European flights and cut taxes on train travel.

Airlines, for their part, are getting on board. United Airlines began buying SAF in 2013, and in 2016 became the first airline to use SAF on a continuous basis. Last year, JetBlue agreed to purchase SAF from Finnish company Neste and began using SAF on flights from San Francisco. Delta has committed $1 billion to become the world’s first carbon-neutral airline, and signed SAF offtake agreements with two biofuel producers. Japan Airlines said it will start using biofuel made from household waste beginning in 2022. Neste is working with Lufthansa, Finnair and KLM on sustainable fuel programs.

It’s not just passenger carriers. Last year, Amazon Air, logistics arm of the online retailer, said it plans to buy 6 million gallons of SAF via a division of Shell and produced by World Energy. 

Another encouraging sign is the ability to push the envelope on SAF’s limitations. Late last year, for example, aircraft engine maker Rolls-Royce announced it is testing 100 percent SAF on next-gen engines.

Depending on who you ask, it could be between 10 and 30 years before electric and hydrogen planes are hurtling through the skies in significant numbers.

And fuel makers are getting pumped up about SAF. In September, for example, Shell Aviation and Neste agreed to collaborate to increase the production of SAF. That sort of partnership — Shell and Neste are also SAF competitors — will be needed to bring greener aviation fuels to scale. So, too, will the participation of airports, plane manufacturers, fuel blenders and other parts of the aviation value chain.

Notably, the flying public — especially corporate travel buyers — can send critical demand signals to help accelerate sustainable aviation’s growth. For example, Microsoft last year said it would purchase SAF credits from SkyNRG, with the SAF delivered to the airport fueling system used by Alaska Airlines for all flights between its global headquarters in Redmond, Washington, and California.

Given SAF’s limitations, airlines are turning to carbon offsets as the third strategy for making aviation sustainable. CORSIA — "carbon offset" is part of its name — requires operators to purchase carbon offsets to cover emissions. Shell is among the companies making significant bets on offsets, with trading operations on three continents. But offsetting is seen as transitional — and controversial: Some critics view it as greenwash.

Longer-term fixes, such as hydrogen technologies and batteries, stand to make air travel nearly emissions-free. Airplane electrification is gradually gaining altitude, at least for shorter-hop flights. Depending on who you ask, it could be between 10 and 30 years before electric and hydrogen planes are hurtling through the skies in significant numbers. 

And, of course, there’s the option of not flying at all, or at least not as much. Such movements as #flygskam ("flight shaming") and Fridays for Future are having an impact, particularly among younger travelers. And some airlines are feeling the heat. KLM’s Fly Responsibly campaign asks, "Could you take the train instead?"

After all, the most sustainable flight is the one you don’t take.

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