On December 1, 2021, United Airlines made history by flying the first commercial flight with passengers that used 100% sustainable aviation fuel (SAF) for one of the two engines. SAF — which reduces emissions by 80% over conventional fuel — is just one of the technologies the airline has become an industry leader in under the direction of Lauren Riley ’95, chief sustainability officer and managing director of global environmental affairs. Ms. Riley, whose passion for sustainability extends back to her days at Hun, is positioning United at the forefront of aviation’s efforts to reduce emissions and using its power to inspire others — airlines and government leaders alike — to do the same, domestically and globally.

Ms. Riley, who holds bachelor’s degrees in environmental science and art history and an M.B.A., was leading sustainability at Hitachi Consulting in 2019 when United approached her to become their chief sustainability officer, despite her lack of background in aviation.

“They were really looking for people to think outside the box,” she says. She notes that aviation is one of six or seven industries that are considered “hard to abate,” meaning that the solutions do not yet exist at scale to stop emissions altogether.

“Almost every other sector has a reasonable pathway to decarbonize. Aviation has some work to do,” Ms. Riley explains. She was excited to see how she could “impact the industry and, ultimately, emissions globally by stepping in and really trying to work the issue.”

And make an impact she has. Ms. Riley shares that the disruptions to aviation caused by the COVID-19 pandemic forced United “to think about not who we were, but what we wanted to become as we emerged.” In 2020, United made a commitment to reach net zero emissions by 2050 — with a 50% reduction from 2019 emissions by 2035 — all without using carbon offsets, which are widely used by the rest of the industry. 

“We need to make different decisions and support different behaviors so that we can draw down emissions permanently,” says Ms. Riley. “That is going to require investment in technology and new alternative fuels.”

She describes multiple ways that United is working toward its goal, including bringing 900 new aircraft online in the next 10 years, each of which reduces emissions by 20% to 25%. Another alternative that holds promise is electric aircraft for short-distance flights. Then there’s the “golden goose” of SAF — jet fuel derived from renewable or waste products. However, SAF is two to four times more expensive than conventional fuel, so United negotiated tax credits for it in the recent Inflation Reduction Act.

“It sends a signal that the government is backing a transition to SAF, and it helps address some of the economics of SAF,” Ms. Riley says.

United is also funding projects that remove CO₂ directly from the air — direct air capture — using renewable power. The CO₂ can be pumped underground and stored safely or converted into a type of SAF. The technology is still in its early stages, she says, but she sees it becoming a larger part of the conversation in the next few years.

As a sustainability leader in aviation, Ms. Riley is also trying to make change on a global scale. In November, she participated in the Conference of the Parties of the United Nations Framework Convention on Climate Change (COP27) in Egypt to talk about climate change with U.S. Special Presidential Envoy for Climate John Kerry, National Economic Council Director Brian Deese, and other leaders from around the world.

“We are a global industry — we need coordinated policies across the world,” she says, noting that she was there to help streamline and talk “about how important it is to build upon what is now the foundation in the United States.”

As for how consumers can help, Ms. Riley says that they should buy tickets on airlines that are moving toward sustainability. She’s also a big proponent of getting involved, “whether it’s supporting sustainable aviation fuels or reaching out to your member of Congress and saying, ‘I care about sustainable flying.’”

“I can't sit still right now, knowing that a climate crisis is on our hands,” says Ms. Riley. “It’s really a matter of timing. Can we transition fast enough? If we can do that, I’m really excited to see what the future holds.”