Most would say we must do all we can to prevent that bleak scenario by limiting the harmful impact of human activities. “There is no planet B,” environmentalists point out. 

Ask the billionaire Elon Musk, however, and you may get a very different reply. “We don’t want to be one of those single-planet species,” Musk said in 2021 at the launch of a SpaceX rocket into orbit. “We want to be a multi-planet species.” Musk added that he is “highly confident” that SpaceX will land humans on Mars in the near future.

It’s a mindset akin to that of the Krypton scientist Jor-El, father of DC Comics’ Superman: As your planet explodes, send your offspring away in a space pod to ensure the survival of your species elsewhere in the galaxy. And indeed, Musk doesn’t seem to have let go of his childhood fascination with dashing, planet-hopping superheroes. 

Growing up in Pretoria, South Africa, “I read all the comics I could find, or that they let me read in the bookstore before chasing me away,” Musk has said in a documentary. In those tales, superheroes vanquished evil on Earth and beyond, and humans and other species faced off in faraway galaxies. 

The Musk we know today—the bombastic entrepreneur, admired and abhorred around the world—has styled himself as the embodiment of these fictional characters: a man who believes in his ability to singlehandedly save humanity. His superhero philosophy puts him at odds with environmentalists, who believe in the power of the collective, rather than that of any individual “great man,” to solve humanity’s greatest challenges. 

And it’s one clue to unpacking a fundamental conundrum about Elon Musk. Why is a person whose technology for electric vehicles, solar energy, and energy storage has done so much to advance the green transition so reviled in the environmentalist community? Why do climate activists abandon his social media platform and mock him at their protests? How green is Elon Musk, really? The answer requires a journey across time and into space. 

The year of Musk’s birth, 1971, was a turning point for humanity. It was the first year humans lived beyond the planet’s biocapacity, scientists at the Global Footprint Network calculated decades later. In the U.S., awareness was rising about smog, acid rain, and the contamination of water supplies; in 1970 the first Earth Day was held, the Environmental Protection Agency was created, and the Clean Air Act was passed. 

But environmental concerns wouldn’t have ranked high on the young Musk’s radar. As a boy, as Walter Isaacson recounted in his recent biography, Musk was sent by his father to several “survival camps” where he had to literally fight to get food, once losing 10 pounds. On another occasion, he was beaten so badly by bullies at school that he was hospitalized. 

The boy Elon found an escape, and a source of inspiration, in the moral certainty of his favorite superheroes, he later said in an interview: “I mean, they’re always trying to save the world, with their underpants on the outside or these skintight iron suits.” He looked to science fiction for philosophical guidance as well. One of his favorite books growing up, he told Isaacson and others, was The Hitchhiker’s Guide to the Galaxy, published when he was eight. The satirical story follows the only man to survive the destruction of planet Earth and his travels in outer space. Among Musk’s takeaways from the book, he said in a CBS interview, is that “the universe is the answer.” (Emails to Tesla and to Musk seeking comment for this story were not returned.)

Confined for now to planet Earth, Musk was fascinated by the New World, and more specifically, the United States. It was the land his superheroes hailed from, and of the unbridled, free-spirited capitalism of President Ronald Reagan and the economist Milton Friedman. (Many years later, Musk would invoke Friedman in calling a Biden administration spending bill “trickery,” and echo Reagan, telling the telling the Wall Street Journal that “government should, I think, just try to get out of the way and not impede progress.”)

Musk ejected himself from the turmoil of apartheid-era South Africa at 17 to enroll at Queen’s University in Canada, where his mother’s relatives lived. He has said he made this decision in part to avoid compulsory service in the South African military. “Who wants to serve in a fascist army?” he said. As soon as he could, he transferred to the U.S. college system, pursuing degrees at the University of Pennsylvania and Wharton, and ending his academic career at Stanford, where he was admitted to a doctoral program but dropped out to pursue entrepreneurship. 

Musk never lost his superhero mindset. As Sam Altman, the CEO of OpenAI, told Ronan Farrow in a recent New Yorker profile: “Elon desperately wants the world to be saved. But only if he can be the one to save it.”

Looking at his track record of developing technology for electricity and renewable energy, there’s certainly a case to be made that Musk has not just proved himself to be green; he’s super-green. 

“Elon Musk will go down in the history books as having helped the transportation sector from fossil fuel to zero-emissions electrification,” said Margo Oge, a former director of the EPA’s Office of Transportation and Air Quality, who has at times been critical of Musk, in an interview with Fortune. “We would not find ourselves where we are today, with trillions of dollars invested in decarbonizing transport, if it wasn’t for him.” 

But before delving into those achievements, let’s consider what “green” even means when it comes to Elon Musk. 

In a literal sense, Musk seems to be no fan of green. From his first internet startup, Zip2, to the gigantic headquarters and factories of Tesla, Musk’s go-to color palette has been monochromatic: white for his sober, modernistic office interiors and factory exteriors; black for the highways and parking lots that surround them; and silver gray, deep red, or blue for the cars he makes. Not for him the tree-lined walkways, native grasses, and shrubberies that other tech campuses boast: Musk merely seeks order, efficiency, and predictability. 

Musk is also not about “leading by example” on being green. He is one of the world’s most polluting individuals, largely due to his commutes by private jet between Los Angeles, Austin, San Francisco’s Bay Area, and other corporate locations. The burnt-up fuel trail Musk’s jets leave behind is enormous, estimated at about 2,000 metric tons of CO2 last year, or about 130 times the average American’s total annual output, one recent study found. It’s worth noting, however, that Elon Musk is still a modest emitter among his billionaire peers. Bill Gates, the author of a book on climate technologies, does far worse. So do fellow tech founders such as Sergey Brin, Larry Ellison, or Larry Page. For several of them, yachts—an indulgence for which Musk has said he has no time—are the main culprit.

Nor is Musk aligned with most environmentalists when it comes to population growth. Last year, he tweeted that “population collapse due to low birth rates is a much bigger risk to civilization than global warming” (though he added, “I do think global warming is a major risk”). Musk is particularly irked, he told his biographer Ashlee Vance, when “really smart women have zero or one kid. You’re like, ‘Wow, that’s probably not good.’ ” It’s a logic that may raise some eyebrows, but Musk personally lives by it. He has reportedly had 11 children with three women. 

Musk’s claim to being green is stronger if framed in terms of efficiency: renewable and sustainable energy generated without the mess, fuss, and expense of fossil fuel extraction and consumption. His grand vision as laid out in his Tesla “Master Plan” steers clear of environmental anxiety, with no preamble on the imminent threat of climate change, or the need for action to reduce human impact. It is instead sober, pragmatic, and mathematical, and cuts right to the engineering logic, suggesting that the problem with fossil fuels isn’t just that they are harmful; it’s that they are inefficient and wasteful too. “A sustainable energy economy is technically feasible and requires less investment and less material extraction than continuing today’s unsustainable energy economy,” it reads. 

But it is really his companies’ tech innovations that give Musk green bragging rights—particularly what he has done with fully electric vehicles. It’s a sector that didn’t look particularly promising when Tesla was founded as a startup in 2003, or when Musk invested and became the company’s chairman in early 2004. Several companies had experimented with electric and hybrid cars in the 1990s, but the auto industry had since all but written off EVs as unrealistic. When Tesla launched its first fully electric car, the Roadster, in 2008, Detroit shrugged, and Silicon Valley media smirked. In 2007, even before its launch, the tech industry gossip site Valleywag wrote off Tesla’s long-awaited Roadster as its top “fail” of the year. 

Things started to change when Tesla launched its first mass-market EV, the luxe Model S sports car, which could go more than 200 miles on a single charge, in 2012. Suddenly, the abstract promise of mass-produced EVs had become a reality—sci-fi that came true. 

In the years that followed, Tesla added several more EVs to its lineup, pumped up its production globally, and—in a stunning turnaround—became the most valuable car company in the world, making Musk (at times, depending on Tesla’s stock price) the richest man in the world. After Musk’s electro-shock, many of the world’s largest car companies, including GM, Volkswagen, Volvo, and Mercedes, followed Tesla on the path to building only EVs, though it will take them many years to make that transition. 

Then there’s Tesla Energy, founded as SolarCity in 2006 by two of Musk’s cousins. That company revolutionized solar energy in America for hundreds of thousands of customers, and helped mainstream renewable energy. It did so by offering solar panels for lease (instead of for sale) to everyone from individual homeowners to large businesses, and by financing these massive purchases by repackaging the leases as bonds to investors. While Musk didn’t found the company, he emerged as its biggest investor, and is credited with coming up with the business model. In 2016, he acquired the company, and merged it with Tesla as Tesla Energy. 

By making green tech a commercially viable reality, Musk became a beacon for others to follow, in the auto industry and beyond. Musk’s spectacular success inspired a generation of entrepreneurs. “Elon is the reason I got into this business,” Arcady Sosinov, the CEO and founder of electric charging company FreeWire, told me. 

Chris Raymond, the chief sustainability officer of Boeing, says aviation is waiting for its own Elon Musk moment. “It’s an exciting time,” he told me. “More people now are drawn to the industry, like Elon was.” 

Whether or not one subscribes to a “great man” reading of history, Elon Musk offers a powerful illustration of what a single human can do to alter the direction of our species’ course. Even as Musk has frequently run afoul of government rules (such as safety regulations governing his SpaceX launches), Farrow suggests in the New Yorker that he has become a kind of quasi-governmental figure himself—providing (and withholding at times) battlefield internet services for Ukraine’s army via his Starlink network, and transporting U.S. astronauts to the International Space Station.

It is for this reason that it’s worth examining Musk’s mindset, the beliefs that have always fueled him. If Elon Musk has shifted our society’s direction, where are we headed? 

We are not headed toward traveling less or taking public transport more. Global car sales are expected to rebound in 2023 to pre-COVID levels, and in the U.S., the percentage of people commuting by public transport remained stuck at a measly 5% in 2019, the latest year for which Census data is available, with 85% commuting by car, truck, or van. For Musk and Tesla, the mobility ideal remains that very American paradigm of a personal, motorized vehicle, albeit with an electric drivetrain.

And while Tesla’s EVs are green insofar as a car can currently be—they emit a lot less CO2 than their thermic counterparts over their lifetime—they are not greener than walking, biking, or taking public transportation. Environmentalists have also pointed out that the extraction of materials used to make EVs itself causes substantial damage and human misery, and that an electric car is only as green as the energy sources of the grid it pulls electricity from.   

A decade ago, Musk seemed to consider getting into public transportation with his tunnel construction firm the Boring Company when he mused about creating a “hyperloop”—an underground, levitating supersonic train that would take hundreds of passengers from city to city at 600 miles per hour. Over the years, though, the idea seems to have fizzled out. Now, instead of high-speed passenger trains that stop at stations, Musk’s Boring Company has shifted its focus to superfast individual vehicle travel. The Loop project, nicknamed internally Teslas in Tunnels, would be “an express public transportation system that resembles an underground highway more than a subway system,” explains the Boring Company website. 

If your vision for a green future is walkable cities with fewer cars and parking spaces, Tesla is not leading the way to that end. Individual electric cars may not emit as much CO2 as their thermic counterparts, but they are still bulky, dangerous, and inefficient, and their proliferation distracts from the need for a more radical transformation of urban landscapes and mobility. 

Even if EVs could be the silver bullet for clean transportation, Musk is no fan of the current incentives to get them on the road faster. He opposed President Joe Biden’s 2021 Inflation Reduction Act and other laws injecting billions of dollars in tax credits and subsidies into EV development, despite the fact that his companies have received billions in taxpayer loans, subsidies, and government contracts.

This resistance to government investment baffles ex–EPA director Oge, who ran the agency’s Office of Transportation and Air Quality from 1994 to 2012. “In 2018, I would say ‘Elon Musk has done so much for the environment, and he is really green, he believes in green investments,’ ” she told me. “But now I don’t know any more what he believes. I don’t know if we’re talking about the same man that I remember from the Obama years.” Perhaps, she posited, Musk has become a “free marketeer now that he’s the market leader.” 

Then there’s Musk’s ambition to make humanity a multi-planetary species via his rocket company, SpaceX. There is a “planet B” in Musk’s mind: Musk has said that he truly does want to move to Mars. “Especially if I’m getting old, I’ll do it. Why not?” he told the Financial Times last year. He’s not the only billionaire with such comic-book-like aspirations, but SpaceX was the first private company to successfully launch a spacecraft into orbit and return it to Earth, and the first to launch a crewed spacecraft to dock with the International Space Station. 

Of course, Musk’s interstellar ambitions are doing plenty of environmental damage here on Earth: Launching a rocket may be the single worst action anyone could take to pollute Earth’s atmosphere—though their limited number has so far shielded them from regulatory constraints that apply to other modes of transport. (In less than 3 minutes, the SpaceX’s Falcon 9 emits more CO2 than a typical car does in 25 years.)   

“Just in terms of environmental impact, it’s hard to think of a more environmentally unfriendly, irresponsible way to act than having a space hobby,” Mike Berners-Lee, author of the book There Is No Planet B, told Fortune. 

Berners-Lee also scoffed at the idea of decamping to Mars. “You’re better off to live on the bottom of a uranium mine,” he said. “It’s a hideous way of spending time.”

As for finding another livable planet in a galaxy far away, Berners-Lee pointed to research showing that the most likely candidate is at least four light years away. Even in the most optimistic scenario, that would mean about 40 years of space travel, with no guarantee of success. 

“Any billionaire that squanders their spare billions on this kind of ridiculous self-indulgent hobby is just incredibly selfish,” Berners-Lee said. “It spells out how little they care about humanity.” 

Where does this leave us? How green is Elon Musk, all things considered? I would offer this: In a world that remained stuck for too long in 20th-century technologies, Musk’s arrival has been like a bolt of green lightning. He altered the energy and mobility status quo, and proved that a greener future is possible, with fewer compromises than anyone previously imagined. 

But whether Musk will be seen as a force for environmental good by those living in the 22nd century or beyond remains an open question.

It’s tempting to imagine the comic-book-reading child Musk regarding the adult he grew into. In one sense, he is living proof of how much an individual entrepreneur can accomplish in a capitalist economy, and how few barriers persist in the face of sheer willpower. Whether launching rockets or mass-producing affordable electric cars, Musk the genius engineer made the impossible possible. Musk the heroic entrepreneur stood at the brink of bankruptcy several times, and almost as many times bailed himself out, either through his unearthly work ethic, or by pumping his last millions into improbable-seeming moonshot projects, many of which paid off handsomely. 

But let’s be clear: Musk hasn’t saved the world. His accomplishments in green technology thus far still have made only a small dent, given the sheer magnitude of the challenge of transforming the energy economy. Despite Musk’s contributions, CO2 emissions globally are still rising at alarming rates. The exploitation and burning of fossil fuels continues apace. Temperatures have already risen about one degree Celsius above 20th-century averages and continue to rise. Unprecedented storms wreak havoc, and forests around the world burn.

Sure, Musk has boldly gone where no one has gone before, and several times he has snatched victory from the jaws of defeat. But that’s where the comparisons to Superman and Iron Man end. Superheroes can bend reality, time-travel, and use magic to transcend what’s physically possible. Elon Musk can’t.

Perhaps it is us, as a society, who need to let go of the fantasy of any one superhero or technological innovation changing the status quo on climate change. To address the crisis humanity faces, technological innovations are necessary, but not sufficient. Individual and collective choices, government policies, and international agreements make up the other pieces of the puzzle. 

Individual humans have flaws, no matter how innovative or visionary they are. Musk is no exception to that rule. And even if he were a flawless superhero, we would need many more than one Superman to make a green transition happen. We’d need a superhero universe. 

Or better still, an entire species, committed to that goal. 

This article appears in the October/November 2023 issue of Fortune with the headline, “How green is Elon Musk, really?”