4 sustainability experts on how they’d spend Elon Musk’s $100 million climate commitment

It’s not just carbon capture that needs the cash.

If you had $100 million to spend, what would you do with it? That’s the amount of money Elon Musk has stated he’ll be spending on combating climate change, though he’s set on one particular type of technology: carbon capture. Unlike renewable energy or energy efficiency projects, carbon capture aims to zap carbon dioxide out of the air, either passively from the air or at industrial sites with lots of emissions.

But is that the best way to use $100 million to fight climate change? Some experts agree that carbon capture is ideal, while others say we should focus more on changing policy and energy use habits to lower our giant carbon footprint before trying to remove it out of thin air. We asked four sustainability experts across the realms of policy, technology, and climate science what they would do if they could drop $100 million on any sustainability project of their choice, and what they said might surprise you.

Carbon capture is the way to go

For Natalie Mahowald, a professor of climate change engineering at Cornell University, it’s obvious that we have to do more than just move to renewable energy in order to stop the devastating effects of climate change. “When I think of the big issues of sustainability, I think of the eradication of poverty, biodiversity, as well as all the pollution problems,” she says. And while the world is going to have to tap into many buckets to keep the climate from rising above three degrees Celsius, carbon dioxide removal has to be a part of the recipe.

This is largely because there are things that simply won’t be able to operate without fossil fuels for a while—think air travel. If you’ve traveled on a flight recently, you may have noticed that airlines have been offering carbon offsets, often in the form of reforestation projects. It’s true that trees and forests act as an amazing natural carbon sink, but Mahowald says “there’s just not enough land to get enough carbon into.”

So, beyond just working to plant trees and take care of forests, she argues that Musk should take that $100 million and give out donations of a million or so dollars to many different groups to see what actually works.

“There are so many great ideas that need people to look at them and figure out what to do next and scale them up,” Mahowald says. The options range from converting atmospheric carbon dioxide to fuel to using it in mineralization, essentially turning the gas into a solid that can be used in things like construction. Then in a few years, we can circle back and see which technologies are scalable to handle the massive infrastructure in place now that emit billions of tons of carbon dioxide.

Fighting industrial carbon emissions

If Jason Smerdon, a professor of ocean and climate physics at Columbia, had $100 million to spare, he wouldn’t necessarily focus his efforts on carbon capture and sequestration. That doesn’t mean the sector doesn’t have plenty to work on. Right now, he says that the carbon capture technology today looks kind of like solar technology—we’ve got the tools in our hands, and now it’s a matter of figuring out how to scale that tech up so it can be cost-effective.

But, there are still some issues out there for which there are not really any plausible solutions right now—namely, alternative fuel options for the industrial sector.

“Just thinking through other areas where the technology doesn’t even exist, I’d say industrial sector emissions,” he says. “There are multiple industrial processes that don’t really have fossil fuel alternatives. Things like metallurgy which require high temperatures for things like steel, we really don’t have significant fossil fuel alternatives.”

For context, every ton of steel creates two tons of carbon dioxide exhaust, which all in all makes up around eight percent of global carbon dioxide emissions worldwide. Carbon capture could of course play a role, but Smerdon says that money should be prioritized for these unsolved issues that desperately need addressing over technology that we already have solid tools for.

Taking care of natural carbon sinks—forests

Some of the most incredible carbon capture and sequestration has been around literally forever: trees, soil, and forests. But planting trees all over the place isn’t a foolproof way to remove the carbon from our atmosphere, especially since climate change is putting forests in dire situations.

“You don’t have to look far to realize that forests and trees on this planet are increasingly in crisis,” says Jonathan Overpeck, an interdisciplinary climate scientist at the University of Michigan. A tree is only as good at capturing carbon as its surroundings allow it. So while a lush forest may be an excellent carbon sink, if that forest were to burn up in a wildfire, you can forget any carbon capture coming out of it. In fact, the opposite is true. “Those wildfires in Australia [in 2020] emitted more carbon than all the rest of [the country’s] emissions,” he says.

So instead of using millions of dollars to plant trees—or to essentially build a high-tech version of what trees do naturally—Overpeck says we need to dig deep into making sure that the trees we already have planted remain healthy and happy enough to do their carbon sinking job. Not to mention, trees do a whole lot more for the world than just capture carbon—they are home to great swaths of biodiversity, ensure clean water supply, and give us the oxygen we literally need to survive.

So while 100 million dollars for technology is great, Overpeck thinks it could be put to better use by protecting what we already have. “That’s a much bigger job,” he says. “We could use some money to figure out technological carbon capture, but we’ve got to protect the biological natural carbon capture first.”

Cutting carbon at its source

In a perfect world, we’d already have switched most, if not all, of our energy to more sustainable options than coal, natural gas, and oil. Unfortunately, we just aren’t there yet, and it’s not completely the fault of pricey technology. A sustainable future that relies less on carbon requires a whole lot of policy work, and that doesn’t come for free.

Juliette Rooney-Varga, a professor of environmental science at University of Massachusetts-Lowell, says that carbon capture tech is kind of like using a spoon to get water out of a bucket. When there’s not that much water, it might be a fine technique, but right now we aren’t only dealing with a bucket but a massive flood.

“We would be a lot better off stopping the flood at the source,” she says. “And whether we like it or not, the real solutions require policy.”

So instead of throwing millions of dollars at new technologies, Rooney-Varga argues we’ve got to start with those not-so-glamorous sustainability initiatives that we already know a lot about: bringing down the cost of renewable energy, boosting energy efficiency in homes, and building less gasoline-hungry transit systems. In the long run, these policies will save us a chunk of carbon in the future, she adds, but right now we need that upfront support.

Starting with these wonkier, less shiny actions can set a better stage for a cleaner world for everyone.

Sara Kiley Watson
Sara Kiley Watson

Sara Kiley Watson is an assistant editor at PopSci. Her work has also been featured in NPR and Business Insider. Contact the author here.