This article is part of a special report on Climate Solutions, which looks at efforts around the world to make a difference.
LONDON — One day late in 2023 an almost-empty commercial airliner is expected to lift off on a trans-Atlantic flight between Britain and the United States that Prime Minister Boris Johnson casts as a once in a generation breakthrough for aviation and the battle against climate change.
With characteristic boosterism, Mr. Johnson has compared the event to the brave first nonstop flight across the Atlantic by a Vickers biplane in 1919, when British World War I veterans Jack Alcock and Arthur Brown struggled from St. John’s, Newfoundland, to Galway, Ireland.
Mr. Johnson’s transport secretary, Grant Shapps, says next year’s flight will be nothing less than the dawn of “an era of guilt-free flying” for passengers worried that the aviation industry has so far contributed little to the scramble to reach anything like a “Net-Zero” world.
Why all the excitement? And is it warranted?
The flight will be powered solely by sustainable aviation fuel or SAF, jet fuel that is made from greener processes and raw materials that range from cooking oil, solid waste and crop residue to synthetic kerosene made from hydrogen and recycled carbon.
Pollution will still spew from the jet’s engines but the fuel is considered “sustainable” because much of the carbon it emits — often up to 80 percent of the carbon emitted from normal fuel — has already been absorbed from the atmosphere by the raw material or would have been released anyway if it had not been turned into jet fuel.
The British government is labeling it a “net-zero” flight, although there will probably still need to be some purchases of carbon offset credits to make the numbers add up.
And for the flight to signal a true change in the impact of air travel on the environment, the production of sustainable aviation fuels would have to ramp up to levels that are extremely ambitious and distant, goals requiring an enormous investment in production and infrastructure by fuel manufacturers.
For this and other reasons, some critics dismiss the flight as a headline-chasing gimmick.
“To claim we can fly guilt-free any time soon is a misleading and dangerous message to give to the public,” said Tim Johnson, the director of the British campaign group the Aviation Environment Federation, who sits on the government’s “jet zero” advisory council.
Besides unrealistic projections of the availability of fuel, the government and industry both plan to continue expanding the number of passengers and miles flown without taxing aviation fuels or making other tough policy and technology changes to reduce emissions, he said.
Dan Rutherford, a program director at a Washington-based research body, the International Council on Clean Transportation, noted that the flight is not as nearly groundbreaking as being projected: United Airlines has already flown an airliner from Houston to Washington, D.C., using 100 percent sustainable fuel in one engine; Airbus has done the same thing in France; and the main hurdle for the trans-Atlantic venture will be securing a one-off exemption to fuel regulations that limit the total amount of sustainable fuel an aircraft can use to a 50 percent blend with normal jet fuel.
Indeed, when the British government announced in May that it would host a competition among airlines and other industry players to take part in the flight, it admitted that one of the goals was to “provide a positive news story about the transition to SAF to increase consumer confidence in the safety and environmental benefits of SAF.”
Just like the trans-Atlantic flight, the aviation industry’s broader promise that it will reach net-zero emissions by 2050 relies enormously on sustainable fuel, despite a significant shortage and few government initiatives to help it compete with the much cheaper traditional fuel, kerosene.
“I am baffled by the lack of attention that governments here and around the world are paying to the fact that we simply don’t have the capacity to make all the SAF everyone is relying on,” said one senior British fuel industry executive who did not wish to be named so he could protect his relationship with the government.
A transport association spokesman said last week that the group expected 125 million liters of sustainable fuel to be produced this year, up from 100 million liters last year, but still well under 1 percent of total consumption.
In October 2021, the association projected that its 2050 goal would require production of 7.9 billion liters of sustainable fuel by 2025, rising to 23 billion liters in 2030 and 449 billion liters in 2050.
The spokesman acknowledged last week that the 2025 output was now likely to fall short, reaching five billion liters, but insisted that the transport association still believed the 2050 target of more than 3,700 times this year’s output remained achievable “with appropriate government policy support.”
Even the reduced 2025 estimate of five billion liters still requires a 40-fold increase in output in just three years, and with each new refinery taking from three to 10 years to come online there is little sign of the required surge of investment, especially from the giant oil firms.
When Prime Minister Johnson was asked by reporters about his decision to take a private jet from London to Cornwall rather than a four-hour train ride to attend a climate-focused summit in June last year, he defended himself by claiming to be leading the world on sustainable fuel.
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“If you attack my arrival by plane,” he said, “I respectfully point out that the U.K. is actually in the lead in developing sustainable aviation fuel. One of the points in the 10-point plan of our green industrial revolution is to get to jet zero as well as net zero.”
Mr. Rutherford of the International Council on Clean Transportation called that “the most bizarre statement I have heard on this whole issue.”
“It was just completely wrong and it was amazing that he got away with saying that,” he said. “The U.K. produces almost zero commercial SAF. The U.S. has a large plant up and running at Paramount, outside Los Angeles, and there is production in Europe, but the U.K. is behind the curve.”
A small amount of sustainable fuel has been delivered to one airline, British Airways, by one plant, the Phillips 66 Humber refinery in northern England, since a first shipment in March this year.
Phillips 66, based in Texas, says its Humber plant can produce about 25 million liters a year, with plans to increase that to more than 66 million liters by 2025.
The British government has given 15 million pounds ($18.4 million) in funding to eight planned sustainable aviation fuel projects, and the aviation minister Robert Courts says it is now “ramping up our efforts to help companies break ground on trailblazing SAFs, supporting the U.K. industry with £180 million of funding over the next three years.”
Real progress remains slow. One of the firms that won some of the British government’s funding for sustainable aviation fuel, Velocys, announced in 2019 that it would start production in five years at the refinery in Immingham, near the Humber Estuary.
Now, construction at the site has still not begun and the firm continues to say that it is five years away from commercial production.
A new British policy to be announced during the Farnborough Airshow, July 18-22, is expected to include mandates forcing British-based airlines to use a minimum amount of sustainable aviation fuel, which is aimed at stimulating demand for a product that is still about three times more expensive than kerosene jet fuel.
The European Union is in the process of shaping similar mandates but Mark Corbett, the founder of Thrust Carbon, which builds software to help clients monitor their emissions, said the missing factor remained “serious investment by the industry and a sense of urgency and leadership by governments around the world.”