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Hello hello and welcome back to The Spark! 

This edition of the newsletter is coming to you with impeccable fall vibes from Boston. 

I’m in town for our first annual ClimateTech event, and one of the sessions that I’m especially excited to be moderating this week is called “Solving the Hard-to-Solve Sectors.” It’s a label that gets thrown around a lot in the climate technology space, and it lumps together a few industries that are crucial to our world but tend to be forgotten about when it comes to innovation. 

So let’s take a sneak peek into this ClimateTech session and untangle what these sectors are, what’s so hard about them, and what approaches companies are taking to clean them up. 

Why is heavy industry such a climate nightmare? 

Usually, when people talk about hard to solve sectors, they’re referring to heavy industry, including steel, cement, and chemical production—building blocks for our roads, buildings, and most of the products we use every day. 

Other sectors like transportation and food might get more attention, but this isn’t some small piece of the climate change pie—industry accounts for about 20% of global greenhouse gas emissions. 

There are a couple major reasons why emissions from heavy industry are so hard to cut. 

First, the processes tend to be wildly energy intensive. Producing steel, for example, requires temperatures of over 1600 °C (2900 °F). Getting furnaces this hot means burning a lot of fossil fuels, often coal. 

Different heat sources like hydrogen and biofuels can sometimes be swapped in to help cut emissions. But there’s a second problem: in some cases, carbon is tied up in the chemical process of making a product. 

Take cement production, for example—I won’t get too deep into the chemistry, but basically cement starts its life as limestone, which is mostly calcium carbonate, and it needs to be turned into lime, or calcium oxide. This process requires high heat, which sloughs off the carbon and oxygen in the limestone—releasing carbon dioxide, the famous greenhouse gas. 

So even if there’s an alternative fuel to heat up the kiln, cement production has emissions baked in. 

And for some industrial products oil and natural gas are the starting point. Plastics are a classic example—most single-use plastics are derived from fossil fuels. This is the case for other chemicals too, like the detergents in your hand soap or fragrances in your perfume.

The icing on the cake is that the sheer size of industrial facilities means that it can be difficult and very expensive to make changes. A major steel mill can cost upwards of a billion dollars to build, and they usually operate for decades—so companies looking to cut emissions in the future need to invest a lot of money in new technologies, and soon.

What can we do about it?

New, decarbonized ways to produce steel, cement, and chemicals are largely still in the research or pilot stage, and there isn’t a clear winner yet for any of these industries. But there are a few approaches that are gaining momentum. 

Using hydrogen as an alternative fuel could be one of the most straightforward ways to cut emissions from industries like steel. Some equipment would need to be adjusted, but burning hydrogen is closest to the approach used today, which mainly relies on coal or natural gas. At ClimateTech, I’ll be speaking with Maria Persson Gulda, CTO of H2 Green Steel, to discuss the role hydrogen can play in steel production. 

Green hydrogen was one of our 10 Breakthrough Technologies in 2021—you can read more about its potential, and possible challenges, here. 

Electrification is another route some startups are going after—Boston Metal is trying this in steel, and at our event this week I’ll be chatting with Leah Ellis, co-founder and CEO of Sublime Systems, a startup working to bring electrochemistry to the cement industry. Substituting electricity for heat will require coming up with enough renewable energy to run the process.

Leah Ellis was one of Technology Review’s 35 Innovators under 35 in 2021—read more about her and about Sublime systems here. 

Capturing carbon dioxide could also be an essential part of cutting emissions. The technology is still expensive today, and where the carbon dioxide goes after it’s captured can be a key detail in how much the process actually reduces emissions. 

Startup Twelve is working to transform carbon dioxide into usable products, from fuels to plastics. I’ll be chatting with Kendra Kuhl, co-founder and CTO of Twelve. Kendra Kuhl was also on our list of 35 under 35, in 2016. Dive deeper on Twelve and her story here. 

Keeping up with Climate

To mark the start of ClimateTech, James Temple, our senior editor for energy, wrote a timely essay about how the dangers of climate change are accelerating, what we can do about it, and how critical this moment is. If you want to feel charged up about climate change, you should definitely give it a read. 

The United Nations body that oversees international aviation finally set a net-zero goal for 2050, a decision years in the making. (New York Times) Some airlines and industry groups had already set 2050 as a target. For more on that goal and what it would take to reach it, check out my piece from earlier this year. 

In other aviation news, a frequent flier tax could help pay for expensive changes needed to cut emissions from flying. (Washington Post) 

Automakers are pouring money into US electric vehicle manufacturing. Incentives in the Inflation Reduction Act are accelerating progress. (Protocol)

A cobalt mine opened last week in Idaho—the only active one in the US. Cobalt is a key mineral used in most lithium-ion batteries in EVs and consumer electronics, and today it’s mostly mined in the Democratic Republic of Congo and processed in China. (NPR)

Electric truck and SUV maker Rivian issued a major recall last week that affects nearly all its vehicles. The issue could affect vehicles’ steering, and the recall comes as the startup works to ramp up production. (Wall Street Journal)

Just for Fun

The Guardian dove deep into pumpkin spice’s meteoric rise: 

“Ten years ago, more people searched Google for ‘candy corn’ than ‘pumpkin spice’ every fall. But now pumpkin spice is the more popular search term worldwide by a wide margin.’”

Did you know that pumpkin spice Spam exists? When are people going to come around and realize that salted caramel is the better fall flavor?

That’s all for this week! Thanks so much for reading, and if you have ideas or suggestions for this newsletter, drop me a line. Until next time!

Casey