While automakers — led by Tesla (TSLA) — have turned out entire fleets of EVs in recent years, aircraft manufacturers are further away from electrifying the industry in the US.
That makes an industry goal to reach net zero emissions by 2050 all the more elusive, energy experts say.
"Aviation is really hard to decarbonize," Samantha Gross, director of energy security and climate initiative at the Brookings Institution, told Yahoo Finance. "You're never going to see a battery-powered 737 [plane] because batteries are heavy."
That’s why the industry is working on a number of green energy solutions like sustainable fuels for larger, long-distance aircraft. Meanwhile, electrifying small planes and helicopters is also on the horizon.
To date, a handful of North American startups have made strides toward the electrification of air travel. And their initiatives are attracting investments frommanufacturing, airlines, and auto giants.
United Airlines (UAL) has a $1 billion agreement with Archer Aviation (ACHR) signed several years ago to purchase up to 200 of the startup’s vertical takeoff and landing vehicles, or eVTOLs. Prior to the United deal, the California-based company partnered with European carmaker Stellantis (STLA).
On an earnings call earlier this year, Archer co-founder Adam Goldstein explained why the company took an investment from the automaker: "When I founded Archer, I knew from watching the EV industry that developing the capability to manufacture our aircraft at high volumes was perhaps the No. 1 enabler of our future success alongside the design and certification of the aircraft," he said.
Meanwhile, Toyota (TM) and Delta (DAL) Airlines have backed Santa Cruz, Calif.-based Joby Aviation (JOBY). The startup’s eVTOLs can travel up to 100 miles on a single charge, or two round trips between JFK Airport and downtown New York City. The company has already delivered one of its aircraft to the US Air Force for testing and training as part of a broader contract with the US Department of Defense.
French plane maker Airbus (AIR.PA) has an internal unit working on its own prototype of an electric air taxi, with a timeline for delivery by the end of this decade.
Last year, American plane manufacturer Boeing (BA) became the sole owner of Wisk Aero, a Mountain View, Calif.-based startup working on eVTOLs. Boeing invested $450 million in the company in 2022.
“What they [startups] are doing today — they’re gathering data on how you operate one of these aircraft in an all-electric environment,” said Dave Shilliday, vice president and general manager of advanced air mobility at Honeywell (HON). The company makes engines and other internal components for traditional and electric aircraft.
The Federal Aviation Administration has yet to fully certify the commercial use of electric planes in the United States, but Archer and Joby hope to commercially launch them in 2025.
Its worth noting, earlier this month China's aviation regulators granted mass production certification for eVTOLs manufactured by Chinese startup EHang (EH).
Autonomous air taxis
Wisk has been working on a fully autonomous air taxi since 2010. The startup's “Generation 6” has a 90-mile range and can carry four passengers and their carry-on luggage. There are no pilots on board, but flights are overseen by humans on the ground.
Wisk recently announced a deal with the City of Sugar Land, Texas, to develop an infrastructure that would eventually allow for Wisk’s autonomous air taxi operations in the Greater Houston region.
The company says its goal is to make the service affordable for all, from college students to professionals. “A trip in Wisk’s aircraft will be comparable to a basic ride-share service cost per mile,” a spokesperson said.
It’s unclear when Generation 6 will receive certification to fly commercially, but the company has already performed roughly 1,700 test flights across multiple generations of the aircraft.
Hybrid planes
Just as hybrid cars have become the interim step to going all electric for the auto industry, the aircraft industry is going electric in steps.
One example is Ontario, Canada-based Horizon Aircraft (HOVR), which is currently working on a 15-foot-long hybrid eVTOL, initially targeted toward municipality use and emergency situations like hospital transports.
"Think of it [the hybrid] as a very practical bridge to a future when all-electric aircraft actually make a lot more sense," said Brandon Robinson, co-founder and CEO of Horizon Aircraft.
The former Canadian fighter pilot envisions that cost-effectiveness will drive more hybrid solutions in the near term.
"When you burn less fuel per unit mile, you not only save yourself costs, but also, from a sustainable aviation perspective, you produce less hydrocarbons," he added.
Sustainable fuel
With battery weight as a main constraint for long-haul electric flights, the industry is currently turning to clean jet fuels for large aircraft.
Virgin Atlantic made history last year by testing out the first transatlantic flight from London to New York City using 100% sustainable aviation fuel (SAF) that is not derived from petroleum.
"The world will always assume something can’t be done … until you do it," read a blog post by founder Sir Richard Branson. "This flight today shows that sustainable jet fuel can be used as a drop-in replacement for jet fuel — and it is the only viable solution for decarbonising long-haul flights."
The UN's International Civil Aviation Organization wants the overall SAF pool to increase from today's levels of less than 1% to 5% by 2030.
"We think that's very achievable,” Gavin Towler, chief sustainability officer at Honeywell, told Yahoo Finance. The company licenses its SAF technologies for chemical plants to startups and oil companies.
There are numerous ways to produce sustainable aviation fuels, but three have emerged as industry forerunners. One of them uses feedstock. The other is linked to ethanol, which is also used in gasoline blends. A third involves converting carbon dioxide and hydrogen to make aviation fuel.
Having one standard for SAFs across the board would help speed up the road to sustainability, Ramanan Krishnamoorti, vice president for energy and innovation at the University of Houston, told Yahoo Finance.
“Price is the biggest challenge that we face today," he said. "The second is also having the same quality of the sustainable aviation fuel across the world."
Ines Ferre is a senior business reporter for Yahoo Finance. Follow her on Twitter at @ines_ferre. Yahoo Finance’s Madison Mills contributed to this report.