American Airlines plane parked at New York's LaGuardia International Airport.

In 1928, a person crossed the Atlantic; in 2018, 4.3 billion passenger trips were recorded. Although some people managed to avoid it even before covid (according to a Gallup poll, about half of Americans don't fly at all), the rest of the US population flies enough to raise the average to about two flights by year.

It takes a lot of energy to get people up in the air, and since energy production comes at an environmental cost, air travel is a major carbon emitter, with a unique challenge compared to other modes of transportation in terms of regards climate change. . Unlike innovations in electric cars, ships, and trains, where the extra mass required to go electric isn't an insurmountable engineering problem, and extension cords aren't 30,000 feet long, fuel fuel is still largely the only way to fly, at least for longer flights. Eighty percent of emissions come from flights of approximately 1,000 miles or more, and for which there is no current viable alternative to fuel.

Every individual has a role to play in reducing emissions. The average American is responsible for around 15 metric tons of CO2 per year, and more than a third of Americans say they are now likely to pay a little more in their airfare for carbon offsets. The rich and famous have an even bigger carbon footprint. Taylor Swift's much-criticized private jet produces about 8,000 metric tons of CO2 a year. But Taylor has nothing to do with the airline industry, whose annual CO2 emissions total a billion metric tons. If the combined airline industry were a country, in addition to having a killer peanut region, it would also have a higher CO2 emission than Germany.

However, the industry emphasizes its small carbon footprint relative to other industries.

U.S. carriers, specifically, carry more than 2 million passengers and 68,000 tons of cargo per day while contributing "just" 2 percent of the nation's greenhouse gas emissions, according to industry trade group Airlines. forAmerica. The aviation industry has become more efficient in recent decades, with US airlines improving their fuel efficiency (based on revenue per ton-mile) by more than 135% between 1978 and 2021. But a focus on how low it seems that 2% figure is part of a growing problem, according to climate analysts who study the aviation sector.

Covid slowed air travel, but it's still expected to triple

Video conferencing may replace a portion of business travel, but as the aviation sector recovers, climate analysts say tripling global air travel in the coming decades, though forecast before Covid, remains a gamble. safe. Passenger travel will increase more slowly, but analysts note that aviation is also used for cargo, which is not affected by business class. That is a major concern for aviation's carbon reduction plans. The industry needs to focus on keeping its share of emissions low, rather than viewing its current share as a reason to move more deliberately, according to climate analysts.

Compared to automobiles, where there is already a decade of progress in electric vehicles, and in the power generation sector, where there have already been significant investments in renewable energy sources that are cost-competitive with traditional sources, the aviation is still in the days of experimentation. of new fuel technology. Electric batteries, at best, have a role to play in shorter regional routes and urban travel, and airlines are making these investments.

Some critics say the aviation industry has been too slow to pursue climate solutions, but admit aviation is a difficult sector when it comes to net-zero targets due to its unique safety and regulatory requirements. Aviation has not been helped by the pandemic, and even its critics say that expecting the last few years to have seen a tidal wave of investment in startup technologies would have been unrealistic given the more pressing financial challenges. Airlines have completed test flights with sustainable aviation fuels and deals with producers of sustainable aviation fuels have started to pile up.

Travelers go through security at San Francisco International Airport during the start of the long Fourth of July holiday weekend in San Francisco, California, on June 30, 2022.

American Airlines finalized an agreement over the summer with biofuel company Gevo to purchase 500 million gallons of sustainable airline fuel (SAF) over five years, part of American's net-zero carbon policy. It describes its climate goals as “aggressive,” including achieving net-zero greenhouse gas (GHG) emissions by 2050. American is the first airline globally to receive validation from the Science Based Targets initiative for its interim climate goals. reduced GHG emissions and the only US airline to report the use of more than 1 million gallons of sustainable aviation fuel in 2021.

Gevo's process for producing low or zero carbon SAF begins on the farm where the raw material is grown. The company partners with farms that use regenerative farming techniques that sequester carbon in the soil. These farms also use precision application of chemicals and fertilizers to reduce the carbon footprint in that process.

The plants Gevo is designing will take those feedstocks (ie field corn) and turn them into ethanol. From ethanol, Gevo transforms it into a product that is chemically identical to standard aviation fuel. The difference between standard aviation fuel and Gevo's SAF is the elimination of any fossil fuel that is used in that production process for heat, electricity, or whatever power is needed.

Instead, Gevo integrates wind, solar, hydrogen, biogas and other renewable energy sources to remove fossil fuels from the process. This will provide a replacement fuel for aviation needs that is net zero, or even net negative, in terms of carbon intensity if carbon capture, utilization and storage (CCUS) is also integrated, according to John Richardson, director of Gevo investor relations. .

VistaJet boss: Electric planes are decades away

SAFs are chemically indistinguishable from standard airline fuel, but their production process is significantly different (and greener) than traditional fuels, although unlike electric vehicles in the automotive sector, there is much debate about which SAF approaches will be the final winners and what compensations they need. that will be done today to support current technologies in development.

Gevo's focus on raw materials is a good example.

Today, the raw materials used in sustainable aviation fuels are not produced on a scale approaching global jet fuel, and that scale issue will remain for years to come as the aviation industry tests approaches competing technologies. The use of raw materials from food production, specifically, may become a bigger problem from an optical perspective in the future.

Several climate analysts told CNBC they are too concerned to focus on scaling up sustainable, feedstock-based jet fuels at a time of growing concern about global food security in a world facing major climate change impacts on agriculture. Gevo emphasizes that he uses residual starches from “inedible field corn” as raw material, which are plentiful in supply and low in nutritional value.

Airbus CEO Guillaume Faury aired the issue on a panel at Britain's Farnborough International Airshow, a five-day exhibition where executives and key figures gather to discuss the future of air travel: "Probably in the long run, in many decades, we will find a very optimized form of sustainable energy, but in the transition, the quick way is to use SAF, and they are already available”, he said.

Judging by its own industry standards, American continues to be a leader in carbon reduction efforts. American received a climate change score of “A-” from CDP in 2021, the highest score among North American airlines and one of only two airlines globally to earn that score.

"We recognize that climate change is urgent and imminent," said Jill Blickstein, vice president of sustainability for American Airlines. "As the world's largest airline, American is committed to developing the tools necessary to decarbonize our operations."

In addition to Gevo, it has invested in Bill Gates' Breakthrough Energy Catalyst, "all aimed at developing the technologies that will help achieve our ambitious sustainability goals," Blickstein said.

Plane decarbonization gets boost from Biden

There are multiple technological approaches to sustainable aviation fuels that can decarbonize aircraft without prolonging the use and reliance on current fossil fuels and green hydrogen technology just got a big boost from the Reduce Inflation Act.

More investor money is expected to flow into green hydrogen as a result of the IRA, with climate analysts describing tax credits as a big driver of sustainable aviation fuels because, apart from science, the biggest challenge in scaling these operations and production of SAF has been the economic incentive. Green hydrogen approaches aim to remove CO2 from the air and mix it with green hydrogen in a form of kerosene that can be cost-competitive with conventional jet fuel. In February 2021, KLM flew for the first time a Boeing 737 airliner from Amsterdam to Madrid powered by 500 liters of synthetic kerosene, from energy giant Shell, mixed with traditional jet fuel.

Recently announced deals with startups in the space were already in the works with major airlines even before the IRA, including Twelve, which recently signed a deal with Alaska Airlines and Microsoft for its approach to creating sustainable fuels using carbon captured from the air, water and renewable energy. Alaska, which has used SAF blends since 2011 on specific routes, noted that there is still a long way to go: currently, less than 1% of the total fuel available is SAF, and its cost is three to five times higher than the fuel for conventional aircraft.

Delta Air Lines recently signed the largest U.S. aviation deal for green hydrogen fuels with Louisiana-based DG Fuels, which uses residual CO2 as a feedstock, and in its announcement gauged the scope of the challenge by stating that the existing global supply SAF could operate a fleet the size of Delta for a day.

At the moment, electric vehicles are far ahead of the innovation curve, with many more years of testing and government policy to support the transformational growth of the transportation sector.

But not everyone sees SAF as the solution, particularly given the growth trends in the industry. At the recent Farnborough International Airshow, activists and climate activists rejected the industry's emphasis on SAFs, urging them to "get real" and offer more meaningful climate solutions. Instead of SAF, slow growth and less travel and fewer flights are proposed as a way to address the problem, perhaps by reducing domestic flights and encouraging and improving rail travel.

Analysts warn that all the effort going into aviation's carbon-free future shouldn't eliminate even more important replacements for air travel, such as high-speed rail. But for aviation, the goal must be the same as in other sectors, with its emissions peaking as soon as possible. And the choice that seems clear today is that aviation stays on the path of fuels, unlike cars, where electricity is the future. Whichever form of fuel production produces the fewest emissions with the most profit and profitability will win, and that is what no player in aviation knows for sure today.