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This week I fell down a bit of a rabbit hole and developed a mild obsession with flying cars—or the version of them that’s hot right now in Silicon Valley, at least.
Some companies think it’s time the aviation industry got a makeover, and many are betting it’ll come in the form of eVTOLs: electric vertical take-off and landing vehicles. It’s a horrible acronym for small aircraft that take off and land like a helicopter and fly like a plane. (Typically, it’s pronounced ee-vee-toll, in case you were wondering.)
If eVTOLs can get off the ground and gain regulatory approval, they could change how we think about flight. But that’s a big “if,” and there are other questions for the industry to answer before these new flying vehicles become a reality. So let’s take a look at eVTOLs: what they are, how close they are to taking off, and whether any of this is a good idea for the climate.
What are eVTOLs, and why are so many companies building them?
There’s a range of possibilities for new electric aircraft, but the eVTOL category basically includes anything that takes off and lands vertically. Most of them look like robotic bugs to me, or something a villain might fly in a James Bond movie.
Trying to compare eVTOLs to existing aircraft is tricky. Some call them flying cars, though they typically aren’t really designed to move around on the ground. They’re probably closest to an electric version of helicopters, though they fly using different mechanics.
Whatever you call them, there are literally hundreds of companies working to bring eVTOLs to the skies.
A lot of the excitement centers on the fact that the vehicles could open up new uses for flight: completing last-mile delivery to rural places, transporting people or organs to hospitals, or avoiding the traffic in big metropolitan areas.
I will say that some of these needs could probably be filled by a robust public transit system. (We shouldn’t have to fly to get easily from Newark Airport to downtown Manhattan, a service one eVTOL company plans to offer.) But given the current state of our infrastructure, especially in the US, eVTOL companies see an opening to get people around faster.
What’s the status of these things?
There are some really well-funded eVTOL startups working to build the next big thing in flight. Two of the biggest, Joby Aviation and Archer Aviation, are based in the US. There are also some late-stage startups based in Europe, including Lilium in Germany.
So far, no eVTOLs have launched commercially, though several companies have announced plans to enter commercial service in 2025.
Right now, companies are testing prototypes and showing off what they can do—a company called Autoflight broke the world record for the longest eVTOL flight just last month. The aircraft covered just over 155 miles (250 kilometers)—about a mile longer than the previous record, held by Joby.
But despite impressive test flights, questions remain about how close we really are to seeing commercial eVTOLs hit the skies.
Getting regulatory approval could be a sticking point. Agencies in the US and EU both plan to classify eVTOLs as a special class of aircraft, meaning they’ll be subject to a different set of requirements from conventional aircraft. There’s still some uncertainty about how that whole process will go down, especially in the US.
Still, some companies are charging ahead. Archer began construction on a manufacturing facility in Georgia earlier this year, which could begin production as soon as 2024 and make up to 650 aircraft per year.
What would eVTOLs mean for climate?
Swapping out fossil-fuel-powered aircraft for electric ones could be a climate win.
When it comes to more conventional aircraft, an electric plane charged using an average grid could cut emissions by about 50% compared with a fossil-fuel-powered plane. If electric planes are instead charged using all renewables, emissions cuts jump to a maximum of 88%. Most of those remaining emissions come from battery production—because they’ll probably be flying and charging a lot, batteries might need replacing every year or so.
But when it comes to eVTOLs’ impact on climate, it’s important to consider that the vehicles might not be replacing fossil-fuel-powered airplanes. The idea is to expand flight, so eVTOLs might need to be compared with ground-based vehicles like trains or cars.
There’s not a ton of analysis out there yet, but one study found that an eVTOL traveling 60 miles (100 kilometers) would produce about 30% less in emissions than a gas-powered car. But the eVTOL would be about 30% worse than an electric vehicle.
For more on eVTOLs, including a look at one company that’s decided to start out with a more conventional plane, check out this story.
I also wrote about the barriers to electric flight in a story last year.
Hydrogen-powered planes were voted our 11th Breakthrough Technology this year. Learn more about them here.
Daylight saving time is trash, and I’m not afraid to say it. (Okay, the time change might be impacting my mood a little bit.)
Setting the clocks back an hour in the fall and forward an hour in the spring started as an energy-saving measure. But in addition to being bad for our health, it doesn’t even really work very well.
Artificially changing the time doesn’t seem to affect behavior all that much. And most analyses tracking electricity have found a minimal effect on electricity use. One 2017 analysis found about a 0.34% reduction, and a 2008 Department of Energy report to Congress put the effect at about 0.5%.
We all need to just agree on an alternative and stop this madness. All right, I’ll get off my soapbox now.
Keeping up with climate
New policies could drive a boom in US mining and mineral processing. My colleague James Temple sat down with David Turk, deputy secretary of the Department of Energy, to talk about what the future of critical minerals looks like for the US. (MIT Technology Review)
The Biden administration approved a major new oil drilling project in Alaska. Activists point out that increasing fossil-fuel production doesn’t align with climate goals. (Associated Press)
Silicon Valley Bank melted down on Friday, raising concerns for many tech startups. Sunday night, the government said insurance would cover all deposits, so everyone’s getting their money back. Crisis averted … for now. (Axios)
The US Department of Energy announced a $6 billion program to cut emissions from heavy industry. The funding could offer key help for an industry that accounts for about a quarter of the US’s emissions. (Canary Media)
→ Last year, I wrote about a startup trying to reinvent steel production with electricity. (MIT Technology Review)
Mmmmm … microbe milk. Some companies hope products made by engineered yeasts or fungi can compete with cow and plant milks. (Washington Post)
The Great Salt Lake in Utah is in trouble, with climate change and increased water demand threatening to turn it into a “toxic dust bomb.” But a lake in California could provide a blueprint to avoiding catastrophe. (Grid News)
I loved these photos of floatovoltaics, or solar panels that float on bodies of water. That’s one way to solve possible concerns about land use. (Bloomberg)
Apple added a new setting on iPhones to align charging with availability of renewable energy. The feature is a small but interesting case of demand response, which could be useful for bigger energy consumers like electric vehicles. (Washington Post)