Why investors care about climate tech’s green premium

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

Talking about money can be difficult, but it’s a crucial piece of the puzzle when it comes to climate tech. 

I’ve been thinking more about the financial piece of climate innovation since my colleague James Temple sat down for a chat with Mike Schroepfer, former CTO of Meta and a current climate tech investor. They talked about Schroepfer’s philanthropic work as well as his climate-tech venture firm, Gigascale Capital. (I’d highly recommend reading the full Q&A here.) 

In their conversation, Schroepfer spoke about investing in companies not solely because of their climate promises, but because they can deliver a cheaper, better product that happens to have benefits for climate action too. 

This all got me thinking about what we can expect from new technologies financially. What do they need to do to compete, and how quickly can they do so? 

Look through the portfolio of a climate-focused venture capital firm or walk around a climate-tech conference, and you’ll be struck by the creativity and straight-up brilliance of some of the proposed technologies.

But in order to survive, they need a lot more than a good idea, as my colleague David Rotman pointed out in a story from December outlining six takeaways from this century’s first boom in climate tech. Countless companies rose to stardom with shiny new ideas starting around 2006 before crashing and failing by 2013.

As David put it, there are lessons in that rise and fall for today’s boom in climate technology: “The brilliance of many new climate technologies is evident, and we desperately need them. But none of that will ensure success. Venture-backed startups will need to survive on the basis of economics and financial advantages, not good intentions.”

Often, companies looking to help address climate change with new products are competing with an established industry. These newcomers must contend with what Bill Gates has called the “green premium.”

The green premium is the cost difference between a cheaper product that increases pollution and a more expensive alternative that offers climate benefits. In order to get people on board with new technologies, we need to close that gap. 

As Gates has outlined in his writings on this topic, there are basically two ways to do this: We need to find ways to either increase the cost of polluting products or cut the cost of the version that causes little to no climate pollution.

Some policies aim to go after the first of these options—the European Union has put a price on carbon, raising the cost of fossil-fuel-based products, for example. But relying on policy can leave companies at the whims of political winds in markets like the US. 

So that leaves the other option: New technology needs to get cheaper. 

As Schroepfer explained in his chat with James, one of the focuses at his venture firm, Gigascale Capital, is picking companies that can compete on economics or offer other benefits to customers. As he put it, a company should basically be saying: “Hey, this is a better product. [whispers] By the way, it’s better for the environment.”

It’s unrealistic to expect companies to have better, cheaper products right out of the gate, Schroepfer acknowledges. But he says that the team is looking for companies that can—over the course of a relatively short, roughly five-to-10-year period—grow to compete on cost, or even gain a cost advantage over the alternatives.

Schroepfer points to batteries and solar power as examples of technologies that are competitive today. When it’s available, electricity produced with solar panels is the cheapest on the planet. Batteries are 90% less expensive than they were just 15 years ago.

But these cases reveal the tricky thing about the green premium: Many new technologies can eventually make up the gap, but it can take much longer than businesses and investors are willing to wait. Solar panels and lithium-ion batteries were available commercially in the 1990s, but it’s taken until now to get to the point where they’re cheap and widespread.

Some technologies just getting started today could be the batteries and solar power of the 2040s, if we’re willing to invest the time and money to get them there. And I already see a few instances where people are willing to pay more for climate-friendly products today, in part because of hopes for their future.  

One example that comes to mind is low-emissions steel. H2 Green Steel, a Swedish company working to make steel without fossil fuels, says it has customers who have agreed to pay 20% to 30% more for its products than metal made with fossil fuels. But that’s just the price today: Some reports predict that these technologies will be able to compete on cost by 2040 or 2050

Most new technologies designed to address climate change will need to make a case for themselves in the market. The question for the rest of us: How much support and time are we willing to put in to give them the best shot of getting there?


Now read the rest of The Spark

Related reading

For more on what the former Meta CTO has been up to in climate, read the full Q&A here. There’s a whole lot more to unpack, including work on glacier stabilization, ocean-based carbon removal, and even solar geoengineering. 

For more on the lessons that companies can take away from the first cleantech boom, give this story from my colleague David Rotman a read.

Another thing

The US Department of Energy is putting $33 million into nine concentrating solar projects, as my colleague James Temple reported exclusively last week. 

Concentrating solar power uses mirrors to direct sunlight, which heats up some target material. It’s not a new technology, and the DOE has been funding efforts to get it going since the 1970s. But it could be useful in industries from food and beverages to low-carbon fuels. Read the full story here

Keeping up with climate  

Western battery startups could be in big trouble. While new chemistries and alternative architectures attracted a lot of investor attention a few years ago, the companies are now facing the reality of competing with massive existing manufacturers. (The Information)

California’s largest wildfire of the year has burned well over 300,000 acres so far. Climate change has helped create the conditions that supercharge blazes. (Inside Climate News)

The UAE has been trying to juice up rainfall with high-tech cloud seeding operations. But the whole thing may be more about the show than the science—check out this great deep dive for more. (Wired)

Congestion pricing plans—like the one recently proposed and then abandoned in New York City—can be unpopular with voters. Yet people generally come around once they start to see the benefits. Here’s an in-depth look at how attitudes toward these plans change over time. (Grist)

Air New Zealand backed down from a goal to cut its emissions nearly 30% by the end of the decade. The first major airline to walk back such a promise, the company points to a lack of supply for alternative fuels, as well as delays in new aircraft deliveries. (BBC)

Global methane emissions are climbing at the quickest pace in decades. The powerful greenhouse gas is responsible for over half the warming we’ve experienced so far. (The Guardian

Demand for air conditioning is swelling in Africa. But the industry isn’t well regulated, and some residents are struggling to get reliable systems and keep harmful refrigerant gases from leaking. (Associated Press)

Southeast Asia is home to a fleet of relatively new coal power plants. Pulling these facilities off the grid early could be a major step to cutting emissions from global electricity production. (Cipher News)

Correction: an earlier version of this story misstated the name of Mike Schroepfer’s firm. It is Gigascale Capital.

The race to clean up heavy-duty trucks

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

Truckers have to transport massive loads long distances, every single day, under intense time pressure—and they rely on the semi-trucks they drive to get the job done. Their diesel engines spew not only greenhouse gas emissions that cause climate change, but also nitrogen oxide, which can be extremely harmful for human health.

Cleaning up trucking, especially the biggest trucks, presents a massive challenge. That’s why some companies are trying to ease the industry into change. For my most recent story, I took a look at Range Energy, a startup that’s adding batteries to the trailers of semi-trucks. If the electrified trailers are attached to diesel trucks, they can improve the fuel economy. If they’re added to zero-emissions vehicles powered by batteries or hydrogen, they could boost range and efficiency. 

During my reporting, I learned more about what’s holding back progress in trucking and how experts are thinking about a few different technologies that could help.

The entire transportation sector is slowly shifting toward electrification: EVs are hitting the road in increasing numbers, making up 18% of sales of new passenger vehicles in 2023

Trucks may very well follow suit—nearly 350 models of zero-emissions medium- and heavy-duty trucks are already available worldwide, according to data from CALSTART. “I do see a lot of strength and demand in the battery electric space in particular,” says Stephanie Ly, senior manager for e-mobility strategy and manufacturing engagement at the World Resources Institute.

But battery-powered trucks will pose a few major challenges as they take to the roads. First, and perhaps most crucially, is their cost. Battery-powered trucks, especially big models like semi-trucks, will be significantly more expensive than diesel versions today.

There may be good news on this front: When you consider the cost of refueling and maintenance, it’s looking like electric trucks could soon compete with diesel. By 2030, the total cost of ownership of a battery electric long-haul truck will likely be lower than that of a diesel one in the US, according to a 2023 report from the International Council on Clean Transportation. The report looked at a number of states including California, Georgia, and New York, and found that the relatively high upfront cost for electric trucks are balanced out by lower operating expenses. 

Another significant challenge for battery-powered trucking is weight: The larger the vehicle, the bigger the battery. That could be a problem given current regulations, which typically limit the weight of a rig both for safety reasons and to prevent wear and tear on roads (in the US, it’s 80,000 pounds). Operators tend to want to maximize the amount of goods they can carry in each load, so the added weight of a battery might not be welcome.

Finally, there’s the question of how far trucks can go, and how often they’ll need to stop. Time is money for truck drivers and fleet operators. Batteries will need to pack more energy into a smaller space so that trucks can have a long enough range to run their routes. Charging is another huge piece here—if drivers do need to stop to charge their trucks, they’ll need much more powerful chargers to enable them to top off quickly. That could present challenges for the grid, and operators might need to upgrade infrastructure in certain places to allow the huge amounts of power that would be needed for fast charging of massive batteries. 

All these challenges for battery electric trucks add up. “What companies are really looking for is something they can swap out,” says Thomas Walker, transportation technology manager at the Clean Air Task Force. And right now, he says, we’re just not quite in a spot where batteries are a clean and obvious switch.

That’s why some experts say we should keep our options open when it comes to technologies for future heavy-duty trucks, and that includes hydrogen. 

Batteries are currently beating out hydrogen in the race to clean up transportation, as I covered in a story earlier this year. For most vehicles and most people, batteries simply make more sense than hydrogen, for reasons that include everything from available infrastructure to fueling cost. 

But heavy-duty trucks are a different beast: Heavier vehicles, bigger batteries, higher power charging, and longer distances might tip the balance in favor of hydrogen. (There are some big “ifs” here, including whether hydrogen prices will get low enough to make hydrogen-powered vehicles economical.) 

For a sector as tough to decarbonize as heavy-duty trucking, we need all the help we can get. As Walker puts it, “It’s key that you start off with a lot of options and then narrow it down, rather than trying to pick which one’s going to win, because we really don’t know.”


Now read the rest of The Spark

Related reading

To learn more about Range Energy and how its electrified trailers could help transform trucking in the near future, check out my latest story here

Hydrogen is losing the race to power cleaner cars, but heavy-duty trucks might represent a glimmer of hope for the technology. Dig into why in my story from earlier this year

Getting the grid ready for fleets of electric trucks is going to be a big challenge. But for some short-distance vehicles in certain areas, we may actually be good to go already, as I reported in 2021

Urban Sky Microballoon pictured shortly after deployment near Breckenridge, Colorado.
COURTESY URBAN SKY

Two more things

Spotting wildfires early and keeping track of them can be tough. Now one company wants to monitor blazes using high-altitude balloons. Next month in Colorado, Urban Sky is deploying balloons that are about as big as vans, and they’ll be keeping watch using much finer resolution than what’s possible with satellites without a human pilot. Read more about fire-tracking balloons in this story from Sarah Scoles

A new forecasting model attempts to marry conventional techniques with AI to better predict the weather. The model from Google uses physics to work out larger atmospheric forces, then tags in AI for the smaller stuff. Check out the details in the latest from my colleague James O’Donnell

Keeping up with climate  

Small rocky nodules in the deep sea might be a previously undiscovered source of oxygen. They contain metals such as lithium and are a potential target for deep-sea mining efforts. (Nature)

→ Polymetallic nodules are roughly the size and shape of potatoes, and they may be the future of mining for renewable energy. (MIT Technology Review)

A 350-foot-long blade from a wind turbine off the coast of Massachusetts broke off last week, and hunks of fiberglass have been washing up on local beaches. The incident is a setback for a struggling offshore wind industry, and we’re still not entirely sure what happened. (Heatmap News)

A new report shows that low-emissions steel- and iron-making processes are on the rise. But coal-powered operations are still growing too, threatening progress in the industry. (Canary Media)

Sunday, July 21, was likely the world’s hottest day in recorded history (so far). It edged out a record set just last year. (The Guardian)

Plastic forks, cups, and single-use packages are sometimes stamped with nice-sounding labels like “compostable,” “biodegradable,” or just “Earth-friendly.” But that doesn’t mean you can stick the items in your backyard compost pile—these marketing terms are basically the Wild West. (Washington Post)

While EVs are indisputably better than gas-powered cars in terms of climate emissions, they are heavier, meaning they wear through tires faster. The resulting particulate pollution presents a new challenge, one a startup company is trying to address with new tires designed for electric vehicles. (Canary Media)

Public fast chargers are popping up nearly everywhere in the US—at this pace, they’ll outnumber gas stations by 2030. And deployment is only expected to speed up. (Bloomberg)

Companies need to stop taking the easy way out on climate goals

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

Corporate climate claims can be confusing—and sometimes entirely unintuitive. 

Tech giants Amazon and Google both recently released news about their efforts to clean up their climate impact. Both were a mixed bag, but one bit of news in particular made me prick up my ears. Google’s emissions have gone up, and the company stopped claiming to be “net zero” (we’ll dig into this term more in a moment). Sounds bad, right? But in fact, one might argue that Google’s apparent backslide might actually represent progress for climate action

My colleague James Temple dug into this news, along with the recent Amazon announcement, for a story this week. Let’s take a sneak peek at what he found and untangle why corporate climate efforts can be so tricky to wrap your head around. 

To make sense of these recent announcements, the most important phrase to understand is “net-zero emissions.” 

Companies produce greenhouse-gas emissions by making products, transporting them around, or just using electricity. Some corporate leaders may want to reduce those emissions so they can be a smaller part of the climate-change problem (or brag about their progress). Net-zero emissions refers to the point at which the emissions a company produces are canceled out by those it eliminates. But very different paths can all lead to that point. 

One way to get rid of emissions is to take actions to reduce them in your operations. Imagine, for example, Amazon replacing its delivery trucks with EVs or building solar panels on warehouses. 

This sort of direct action tends to be hard and expensive, and it’s probably impossible for any company to totally wipe out all its emissions right now, given that so much of our economy still relies on fossil fuels. So to reach net zero, many companies choose to disappear their emissions with math instead. 

A company might buy carbon credits or renewable-energy credits, essentially paying someone to make up for its own climate impact. That might mean giving a nonprofit money to plant some trees, which suck up and store carbon, or funneling funds to developers and claiming that more renewables projects will get built as a result. 

Not all credits are all bad—but often, carbon offsets and renewable-energy credits reflect big claims with little to back them up. And if companies are going after a net-zero label for their business, they may be incentivized to buy cheap credits, even if they don’t actually deliver on claims. 

As James puts it in his story, “Corporate sustainability officers often end up pursuing the quickest, cheapest ways of cleaning up a company’s pollution on paper, rather than the most reliable ways of reducing its emissions in the real world.”

This sort of issue is why I tend to be suspicious of companies that claim to have already achieved net-zero emissions or 100% renewable energy. Cleaning up emissions is hard, and if you’ve already claimed victory, I’d say the odds are good that you’re taking an easy way out. 

Which brings us to Google’s news. Google has claimed that its operations have operated with net-zero emissions since 2007. Now it’s not claiming that anymore—not really because it suddenly decided to take huge steps back in how it operates, but because it’s stopped buying carbon offsets on a massive scale. Instead, it’s focusing on investing in other ways to tackle emissions.

So what’s the next step for big companies looking to have a material impact on climate action? James has us covered again: In a 2022 story, he laid out six potential ways to rethink corporate climate goals. 

Instead of buying up credits, companies can instead put that money toward investing in permanent carbon removal. Developing more reliable methods of pulling climate pollution out of the atmosphere and locking it away might be more expensive, but investing in those efforts will help the market mature and support companies that need commitments. 

Companies can also contribute money to research and development for areas that are difficult to decarbonize—think aviation, shipping, steel, and cement. Those sectors touch basically every industry, so helping them make progress could be a worthy use of dollars. 

If there’s one takeaway in this tangle of news, I’d say that we could all ask more questions and dig a little deeper into claims from big corporations. Remember, if something sounds too good to be true, it probably is.  


Now read the rest of The Spark

Related reading

Read more about Big Tech climate action, including why Amazon’s renewable-energy claims might be more complicated than they appear at first glance, in James’s latest story.

And here’s his piece on six ways that we can rethink net-zero climate plans. 

For more on how the climate “solution” of carbon offsets might be adding millions of tons of carbon dioxide into the atmosphere, read this 2021 deep dive.  

KPOP4PLANET

Another thing

A small group of K-pop fans is working to clean up music streaming. Streaming can consume a lot of computing power, and all that energy used in data centers supporting it can mean big-time emissions.

A group called Kpop4planet put pressure on a streaming service to commit to using 100% renewables for its data centers by 2030. And the fans’ organizing paid off, because the service agreed. 

Read more about the power of K-pop fans in this latest story from my colleague Zeyi Yang

Keeping up with climate  

It’s been mixed news this year so far for the EV market in the US. Overall sales are up, but some automakers are seeing deliveries stall. Also notable: Tesla has historically dominated, but it just dropped below 50% of the market for the first time. (Inside Climate News)

New materials that help tackle humidity could make air-conditioning a lot more efficient. Several companies are trying to bring machines based on these desiccant materials to the market. (Wired)

→ I wrote last year about how these moisture-sucking materials could help us beat the heat. (MIT Technology Review)

Electric vehicles are associated with lower emissions over their lifetimes than gas-powered cars, but they don’t start out that way, largely because of the climate cost of building their batteries. This calculator estimates how far you need to drive for EVs to break even with gas vehicles. (PNAS)

Nuclear startup Commonwealth Fusion Systems is selling its high-tech magnets now. The company is still working toward flipping on its fusion reactor. (TechCrunch)

The near-term future of EVs might include gas tanks, since some automakers are building electric vehicles that include gas-powered generators. The difference between these and plug-in hybrids is subtle, but basically these would have simpler guts inside. They could help bring more drivers onto team electric. (Heatmap News)

San Francisco launched a new ferry that runs entirely on hydrogen fuel cells. It’s the first such commercial passenger ferry in the world. One challenge could be securing a reliable source of low-emissions hydrogen. (Canary Media)

File this under weird effects of climate change: Melting ice sheets are making days longer. Ice loss in Greenland and Antarctica makes the Earth wider, slowing the planet’s rotation. It’s only on the scale of about a millisecond per century, but it could be enough to throw off precise timekeeping. (The Guardian)

Rules around tax credits for hydrogen fuel were proposed to ensure that the money went to projects that help the climate. Now those rules seem to be in trouble. (Heatmap News)

Here’s the problem with new plastic recycling methods

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

Look on the bottom of a plastic water bottle or takeout container, and you might find a logo there made up of three arrows forming a closed loop shaped like a triangle. Sometimes called the chasing arrows, this stamp is used on packaging to suggest it’s recyclable. 

Those little arrows imply a nice story, painting a picture of a world where the material will be recycled into a new bottle or some such product, maybe forming an endless loop of reuse. But the reality of plastics recycling today doesn’t match up to that idea. Only about 10% of the plastic ever made has been recycled; the vast majority winds up in landfills or in the environment. 

Researchers have been working to address the problem by coming up with new recycling methods, sometimes called advanced, or chemical, recycling. My colleague Sarah Ward recently wrote about one new study where researchers used a chemical process to recycle mixed-fiber clothing containing polyester, a common plastic. 

The story shows why these new technologies are so appealing in theory, and just how far we would need to go for them to fix the massive problem we’ve created. 

One major challenge for traditional recycling is that it requires careful sorting. That’s possible (if difficult) for some situations—humans or machines can separate milk jugs from soda bottles from takeout containers. But when it comes to other products, it becomes nearly impossible to sort out their components. 

Take clothing, for instance. Less than 1% of clothing is recycled, and part of the reason is that much of it is a mixture of different materials, often including synthetic fibers as well as natural ones. You might be wearing a shirt made of a cotton-polyester blend right now, and your swimsuit probably contains nylon and elastane. My current crochet project uses yarn that’s a blend of wool and acrylic. 

It’s impossible to manually or mechanically pick out the different materials in a fabric the way you can by sorting your kitchen recycling, so researchers are exploring new methods using chemistry. 

In the study Sarah wrote about, scientists demonstrated a process that can recycle a fabric made from a blend of cotton and polyester. It uses a solvent to break the chemical bonds in polyester in around 15 minutes, leaving other materials mostly intact. 

If this could work quickly and at large scale, it might someday allow facilities to dissolve polyester from blended textiles, separating it from other fibers and in theory allowing each component to be reused in future products. 

But there are a few challenges with this process that I see a lot in recycling methods. First, reaching a large industrial scale would be difficult—as one researcher that Sarah spoke to pointed out, the solvent used in the process is expensive and tough to recover after it’s used.  

Recycling methods also often wind up degrading the product in some way, a tricky problem to solve. This is a major drawback to traditional mechanical recycling as well—often, recycled plastic isn’t quite as strong or durable as the fresh stuff. In the case of this study, the problem isn’t actually with the plastic, but with the other materials that researchers are trying to preserve.

The beginning of the textile recycling process involves shredding the clothing into fine pieces to allow the chemicals to seep in and do their work breaking down the plastic. That chops up the cotton fibers too, rendering them too short to be spun into new yarn. So instead of a new T-shirt, the cotton from this process might be broken down and used as something else, like biofuel. 

There’s potential for future improvement—the researchers tried to change up their method to disassemble the fabrics in a way that would preserve longer cotton fibers, but the reported research suggests it doesn’t work well with the chemical process so far. 

This story got me thinking about a recent feature from ProPublica, where Lisa Song took a look at the reality of commercial advanced recycling today. She focused on pyrolysis, which uses heat to break down plastic into its building blocks. As she outlines in the story, while the industry pitches these new methods as a solution to our plastics crisis, the reality of the technology today is far from the ideal we imagine. 

Most new recycling methods are still in development, and it’s really difficult to recover useful materials at high rates in a way that makes it possible to use them again. Doing all that at a scale large enough to even make a dent in our plastics problem is a massive challenge. 

Just something to keep in mind the next time you see those little arrows. 


Now read the rest of The Spark

Related reading

Read Sarah’s full story on efforts to recycle mixed textiles here

I wrote about several other efforts to recycle mixtures of plastic using chemistry in this piece from 2022

For a full account on the state of the hard problem that is the plastics crisis, check out this feature story

Keeping up with climate  

The world has been 1.5 °C hotter than preindustrial temperatures for each of the last 12 months, according to new data. We still haven’t technically passed the 1.5 °C limit set out by international climate treaties, since those consider the average temperature over many years. (The Guardian)

Google has stopped claiming to be carbon neutral, ceasing purchases of carbon offsets to balance its emissions. The company says the plan is to reach net-zero emissions by 2030, though its emissions are actually up by nearly 50% since 2019. (Bloomberg)

Big tech companies are expecting emissions to tick up in part because of the explosion of AI, which is an energy hog. (MIT Technology Review)

A small school district in Nebraska got an electric bus, paid for by federal funding. The vehicle quickly became a symbol for the cultural tensions brought on by shifting technology. (New York Times)

Hurricane Beryl hit the Texas coast this week and did damage across the Caribbean and the Gulf of Mexico. While meteorologists had a good idea of where it would go, better forecasting hasn’t stopped hurricane damage from increasing. (E&E News)

→ Here’s what we know about hurricanes and climate change. (MIT Technology Review)

Earlier this year, the Indian government stopped a popular EV subsidy. Some in the industry say that short-lived subsidies can hamper the growth of electrification. (Rest of World)

The US is about to get its first solar-covered canal. Covering the Arizona waterway with solar panels will provide a new low-emissions energy source on tribal land. (Canary Media)

Electricity prices in the US are up almost 20% since early 2021. But some states that have built the most clean energy have lower rate increases overall. (Latitude Media)

These climate tech companies just got $60 million

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

Some people track sports scores or their favorite artists’ tour set lists. Meanwhile, I’m just waiting to hear which climate tech startups are getting big funding awards from government agencies. It’s basically the same thing. 

Every few years, the US agency that’s often called the “energy moonshot factory” announces such awards for a few companies to help them scale up their technology. (The agency’s official name is the Advanced Research Projects Agency—Energy, or ARPA-E.) The grants are designed to help companies take their tech from the lab or pilot stage and get it out into the world. 

The latest batch of these awards was just announced, totaling over $63 million split between four companies. Let’s dig into the winners and consider what each one’s technology says about their respective corners of climate action. 

Antora Energy: Heat batteries for industry

Let’s start with the company you’re most likely to know if you follow this newsletter: Antora Energy. The California-based company is building thermal batteries for use in heavy industry. I covered the company and its first pilot project last year, and thermal batteries were the readers’ choice winner on our list of Breakthrough Technologies this year. 

In case you need a quick refresher, the basic idea behind Antora’s technology is to store energy from cheap, clean wind and solar power in the form of heat, and then use that heat in industrial facilities. It’s an elegant solution to the problem that renewables are available only sometimes, while industry needs clean energy all the time if it wants to cut its carbon emissions, which amount to a whopping 30% of the global total. 

Antora was awarded $14.5 million to scale its technology. One thing the company hopes to achieve with the cash influx is progress on its second product, which delivers not only heat but also electricity. 

Queens Carbon: Lower-emissions cement

Cement is a climate villain hiding in plain sight, as I’ve covered in this newsletter before. Producing the gray slabs that scaffold our world accounts for about 7% of global emissions. 

The challenge in cleaning up the process lies, at least in part, in the fact that lava-hot temperatures are required to kick off the chemical reactions that make cement—I’m talking over 1,500 °C (2,700 °F). 

Queens Carbon developed a new process that cuts down the temperature needed to under 540 °C (1,000 °F). Still toasty, but easier to reach efficiently and with electricity, the company’s CEO, CTO, and cofounder Daniel Kopp said on a press call about the awards. Ideally, that electricity will be supplied with renewables, which could mean big emissions savings.

Queens Carbon will also pocket $14.5 million, and the funding should help with the construction of a pilot plant currently being built in partnership with a major cement producer, Kopp said on the press call. The company plans to scale up to a full-size plant in late 2028 or 2029. 

Ion Storage Systems: Next-generation batteries for EVs

The world is always clamoring for better batteries, and Maryland-based Ion Storage Systems wants to deliver with its solid-state lithium-metal technology.

We named lithium-metal batteries one of our 10 Breakthrough Technologies in 2021. The chemistry could deliver higher energy density, meaning longer range in EVs. 

Ion Storage Systems is planning to produce its batteries first for military customers. With the funding ($20 million worth), the company may be able to get its tech ready for larger-scale production for the wider customer base of the electric-vehicle market. 

I was really interested to hear about the emphasis on manufacturing from CTO Greg Hitz on the press call, as scaling up manufacturing has been a major challenge for other companies trying to build solid-state batteries. Hitz also said that the company’s batteries don’t need to be squeezed at high pressure within cells or heated up, and they can be more simply integrated into battery packs. 

AeroShield Materials: High-tech insulation for more efficient buildings

Last but certainly not least is AeroShield Materials. Between 30% and 40% of energy we put into our buildings for heat and cooling is lost through windows and doors—that’s about $40 billion per year for residential buildings, said Elise Strobach, the company’s CEO and cofounder, on the press call. 

AeroShield is making materials called aerogels that are clear, lightweight, and fire resistant. They can help make windows 65% more energy efficient, Strobach says. 

Insulation isn’t always the most exciting topic, but efficiency is one of the best ways to cut down the need for more energy and provide a straightforward way to slash emissions. AeroShield is starting with windows and doors but plans to explore other projects like retrofitting windows and producing insulation for freezer and refrigerator doors, Strobach said on the call. The $14.5 million award will help build a pilot manufacturing facility. 

These projects cover a huge range of businesses, from transportation and buildings to heavy industry. The one thing they have in common? All urgently need to clean up their act if the world is going to address climate change. Each of these awards is a big vote of confidence from an agency that’s had a lot of experience in energy technology—but what really matters is what these companies do with the money now. 


Now read the rest of The Spark

Related reading

I spoke with ARPA-E director Evelyn Wang last year about how the agency hopes to shape the future of energy technology. 

To see why readers chose thermal batteries as the 11th Breakthrough Technology, check out this story from April.

Cement is one of climate’s hardest problems, as I covered in a feature story about startup Sublime Systems earlier this year.

collage of cloudy skies with money and a control panel of knobs and indicators

STEPHANIE ARNETT/MIT TECHNOLOGY REVIEW | ENVATO

Another thing

There’s a growing pool of money for scientists exploring whether we can reflect away more sunlight to ease warming caused by climate change. 

Quadrature Climate Foundation is among the organizations providing millions of dollars for research into solar geoengineering. This sort of funding can help scientists pursue lab work, modeling, and maybe even outdoor experiments that could improve our understanding of the often controversial field. 

For more on where the money is coming from and how this might affect our efforts to address climate change, check out my colleague James Temple’s story here

One more issue

We often talk about tech that’s serious business—but technology also has a huge effect on how we have fun. That’s the idea behind our latest print edition, the Play issue

For the issue, I wrote about board games that take on the topic of climate change. Are they accurate about the challenge ahead, and crucially, can they be fun? Check out my take here. (For a more in-depth look at one particular game, a new climate-themed Catan, give this newsletter a read.) 

I’d also highly recommend this feature from my colleague Eileen Guo, who looked into the growing business of surf pools—facilities that bring a usually ocean-based activity onto land. She gave one a spin, and considered how these spots affect places facing water scarcity. 

The whole issue is great—find all the stories here

Keeping up with climate  

A new startup will take sodium sulfate, a waste material from manufacturing lithium-ion batteries, and turn it into chemicals that can go into new batteries. Aepnus Technology calls its approach a “fully circular” one. (Heatmap)

Solugen just scored a loan worth over $200 million from the US Department of Energy. The company uses biology to make chemicals used in industries from agriculture to concrete. (C&EN News)

Some Olympic teams, including the delegation from the US, plan to bring their own air conditioners to the Paris games this summer. It could be a big setback for the event’s climate goals. (Associated Press)

Advanced recycling promises an almost miraculous solution to our plastics crisis, but a close look at the industry reveals some problems. Very little plastic is made with these methods, and the industry is selling them on the basis of some tricky accounting. (ProPublica)

You may not know the name Yet-Ming Chiang, but you’ve probably heard of some of the companies he’s had a hand in starting, including Sublime Systems and Form Energy. Learn more about this MIT professor and serial entrepreneur here. (Cipher)

Running Tide had grand plans to suck carbon dioxide out of the atmosphere with the help of the ocean. Now, the startup is shutting down. Here’s what the company’s implosion means for carbon removal’s future. (Latitude Media)

→ The company was in some rocky waters a couple of years ago, as my colleague James Temple revealed at the time. (MIT Technology Review)

Volkswagen is investing $1 billion in the EV startup Rivian. The deal has the two companies creating a joint venture, and it could provide a path forward for Rivian, which has faced some struggles getting its vehicles to market. (TechCrunch)

Why we need to shoot carbon dioxide thousands of feet underground

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

There’s often one overlooked member in a duo. Peanut butter outshines jelly in a PB&J every time (at least in my eyes). For carbon capture and storage technology, the storage part tends to be the underappreciated portion. 

Carbon capture and storage (CCS) tech has two main steps (as you might guess from the name). First, carbon dioxide is filtered out of emissions at facilities like fossil-fuel power plants. Then it gets locked away, or stored.  

Wrangling pollution might seem like the important bit, and there’s often a lot of focus on what fraction of emissions a CCS system can filter out. But without storage, the whole project would be pretty useless. It’s really the combination of capture and long-term storage that helps to reduce climate impact. 

Storage is getting more attention lately, though, and there’s something of a carbon storage boom coming, as my colleague James Temple covered in his latest story. He wrote about what a rush of federal subsidies will mean for the CCS business in the US, and how supporting new projects could help us hit climate goals or push them further out of reach, depending on how we do it. 

The story got me thinking about the oft-forgotten second bit of CCS. Here’s where we might store captured carbon pollution, and why it matters. 

When it comes to storage, the main requirement is making sure the carbon dioxide can’t accidentally leak out and start warming up the atmosphere.

One surprising place that might fit the bill is oil fields. Instead of building wells to extract fossil fuels, companies are looking to build a new type of well where carbon dioxide that’s been pressurized until it reaches a supercritical state—in which liquid and gas phases don’t really exist—is pumped deep underground. With the right conditions (including porous rock deep down and a leak-preventing solid rock layer on top), the carbon dioxide will mostly stay put. 

Shooting carbon dioxide into the earth isn’t actually a new idea, though in the past it’s largely been used by the oil and gas industry for a very different purpose: pulling more oil out of the ground. In a process called enhanced oil recovery, carbon dioxide is injected into wells, where it frees up oil that’s otherwise tricky to extract. In the process, most of the injected carbon dioxide stays underground. 

But there’s a growing interest in sending the gas down there as an end in itself, sparked in part in the US by new tax credits in the Inflation Reduction Act. Companies can rake in $85 per ton of carbon dioxide that’s captured and permanently stored in geological formations, depending on the source of the gas and how it’s locked away. 

In his story, James took a look at one proposed project in California, where one of the state’s largest oil and gas producers has secured draft permits from federal regulators. The project would inject carbon dioxide about 6,000 feet below the surface of the earth, and the company’s filings say the project could store tens of millions of tons of carbon dioxide over the next couple of decades. 

It’s not just land-based projects that are sparking interest, though. State officials in Texas recently awarded a handful of leases for companies to potentially store carbon dioxide deep underwater in the Gulf of Mexico.

And some companies want to store carbon dioxide in products and materials that we use, like concrete. Concrete is made by mixing reactive cement with water and material like sand; if carbon dioxide is injected into a fresh concrete mix, some of it will get involved in the reactions, trapping it in place. I covered how two companies tested out this idea in a newsletter last year.

Products we use every day, from diamonds to sunglasses, can be made with captured carbon dioxide. If we assume that those products stick around for a long time and don’t decompose (how valid this assumption is depends a lot on the product), one might consider these a form of long-term storage, though these markets probably aren’t big enough to make a difference in the grand scheme of climate change. 

Ultimately, though of course we need to emit less, we’ll still need to lock carbon away if we’re going to meet our climate goals.  


Now read the rest of The Spark

Related reading

For all the details on what to expect in the coming carbon storage boom, including more on the potential benefits and hazards of CCS, read James’s full story here.

This facility in Iceland uses mineral storage deep underground to lock away carbon dioxide that’s been vacuumed out of the atmosphere. See all the photos in this story from 2022

On the side of a road stands a gogoro power station with an enel x system box on the side. Each of the four network station units holds 30 batteries.

GOGORO

Another thing

When an earthquake struck Taiwan in April, the electrical grid faced some hiccups—and an unlikely hero quickly emerged in the form of battery-swap stations for electric scooters. In response to the problem, a group of stations stopped pulling power from the grid until it could recover. 

For more on how Gogoro is using battery stations as a virtual power plant to support the grid, check out my colleague Zeyi Yang’s latest story. And if you need a catch-up, check out this explainer on what a virtual power plant is and how it works

Keeping up with climate  

New York was set to implement congestion pricing, charging cars that drove into the busiest part of Manhattan. Then the governor put that plan on hold indefinitely. It’s a move that reveals just how tightly Americans are clinging to cars, even as the future of climate action may depend on our loosening that grip. (The Atlantic)

Speaking of cars, preparations in Paris for the Olympics reveal what a future with fewer of them could look like. The city has closed over 100 streets to vehicles, jacked up parking rates for SUVs, and removed tens of thousands of parking spots. (NBC News)

An electric lawnmower could be the gateway to a whole new world. People who have electric lawn equipment or solar panels are more likely to electrify other parts of their homes, like heating and cooking. (Canary Media)

Companies are starting to look outside the battery. From massive moving blocks to compressed air in caverns, energy storage systems are getting weirder as the push to reduce prices intensifies. (Heatmap)

Rivian announced updated versions of its R1T and R1S vehicles. The changes reveal the company’s potential path toward surviving in a difficult climate for EV makers. (Tech Crunch)

First responders in the scorching southwestern US are resorting to giant ice cocoons to help people suffering from extreme heat. (New York Times)

→ Here’s how much heat your body can take. (MIT Technology Review)

One oil producer is getting closer to making what it calls “net-zero oil” by pumping captured carbon dioxide down into wells to get more oil out. The implications for the climate and the future of fossil fuels in our economy are … complicated. (Cipher)

Why bigger EVs aren’t always better

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

SUVs are taking over the world—larger vehicle models made up nearly half of new car sales globally in 2023, a new record for the segment. 

There are a lot of reasons to be nervous about the ever-expanding footprint of vehicles, from pedestrian safety and road maintenance concerns to higher greenhouse-gas emissions. But in a way, SUVs also represent a massive opportunity for climate action, since pulling the worst gas-guzzlers off the roads and replacing them with electric versions could be a big step in cutting pollution. 

It’s clear that we’re heading toward a future with bigger cars. Here’s what it might mean for the climate, and for our future on the road. 

SUVs accounted for 48% of global car sales in 2023, according to a new analysis from the International Energy Agency. This is a continuation of a trend toward bigger cars—just a decade ago, SUVs only made up about 20% of new vehicle sales. 

Big vehicles mean big emissions numbers. Last year there were more than 360 million SUVs on the roads, and they produced a billion metric tons of carbon dioxide. If SUVs were a country, they’d have the fifth-highest emissions of any nation on the planet—more than Japan. Of all the energy-related emissions growth last year, over 20% can be attributed to SUVs. 

There are several factors driving the world’s move toward larger vehicles. Larger cars tend to have higher profit margins, so companies may be more likely to make and push those models. And drivers are willing to jump on the bandwagon. I understand the appeal—I learned to drive in a huge SUV, and being able to stretch out my legs and float several feet above traffic has its perks. 

Electric vehicles are very much following the trend, with several companies unveiling  larger models in the past few years. Some of these newly released electric SUVs are seeing massive success. The Tesla Model Y, released in 2020, was far and away the most popular EV last year, with over 1.2 million units sold in 2023. The BYD Song (also an SUV) took second place with 630,000 sold. 

Globally, SUVs made up nearly 50% of new EV sales in 2023, compared to just under 20% in 2018, according to the IEA’s Global EV Outlook 2024. There’s also been a shift away from small cars (think the size of the Fiat 500) and toward large ones (similar to the BMW 7-series). 

And big-car obsession is a global phenomenon. The US is the land of the free and the home of the massive vehicles—SUVs made up 65% of new electric-vehicle sales in the country in 2023. But other major markets aren’t all that far behind: in Europe, the share was 52%, and in China, it was 36%. (You can see the above chart broken down by region from the IEA here.)

So it’s clear that we’re clamoring for bigger cars. Now what? 

One way of looking at this whole thing is that SUVs offer up an incredible opportunity for climate action. EVs will reduce emissions over their life span relative to gas-powered versions of the same model, so electrifying the biggest emitters on the roads would have an outsize impact. If all gas-powered and hybrid SUVs sold in 2023 were instead electric vehicles, about 770 million metric tons of carbon dioxide would be avoided over the lifetime of those vehicles, according to the IEA report. That’s equivalent to all of China’s road emissions last year. 

I previously wrote a somewhat hesitant defense of large EVs for this reason—electric SUVs aren’t perfect, but they could still help us address climate change. If some drivers are willing to buy an EV but aren’t willing to downsize their cars, then having larger electric options available could be a huge lever for climate action. 

But there are several very legitimate reasons why not everyone is welcoming the future of massive cars (even electric ones) with open arms. Larger vehicles are harder on roads, making upkeep more expensive. SUVs and other big vehicles are way more dangerous for pedestrians, too. Vehicles with higher front ends and blunter profiles are 45% more likely to cause fatalities in crashes with pedestrians. 

Bigger EVs could also have a huge effect on the amount of mining we’ll need to do to meet demand for metals like lithium, nickel, and cobalt. One 2023 study found that larger vehicles could increase the amount of mining needed more than 50% by 2050, relative to the amount that would be necessary if people drove smaller vehicles. Given that mining is energy intensive and can come with significant environmental harms, it’s not an unreasonable worry. 

New technologies could help reduce the mining we need to do for some materials: LFP batteries that don’t contain nickel or cobalt are quickly growing in market share, especially in China, and they could help reduce demand for those metals.

Another potential solution is reducing the demand for bigger cars in the first place. Policies have historically had a hand in pushing people toward larger cars and could help us make a U-turn on car bloat. Some countries, including Norway and France, now charge more in taxes or registration for larger vehicles. Paris recently jacked up parking rates for SUVs. 

For now, our vehicles are growing, and if we’re going to have SUVs on the roads, then we should have electric options. But bigger isn’t always better. 


Now read the rest of The Spark

Related reading

I’ve defended big EVs in the past—SUVs come with challenges, but electric ones are hands-down better for emissions than gas-guzzlers. Read this 2023 newsletter for more

The average size of batteries in EVs has steadily ticked up in recent years, as I touched on in this newsletter from last year

Electric cars are still cars, and smaller, safer EVs, along with more transit options, will be key to hitting our climate goals, Paris Marx argued in this 2022 op-ed

Keeping up with climate  

We might be underestimating how much power transmission lines can carry. Sensors can give grid operators a better sense of capacity based on factors like temperature and wind speed, and it could help projects hook up to the grid faster. (Canary Media)

North America could be in for an active fire season, though it’s likely not going to rise to the level of 2023. (New Scientist)

Climate change is making some types of turbulence more common, and that could spell trouble for flying. Studying how birds move might provide clues about dangerous spots. (BBC)

The perceived slowdown for EVs in the US is looking more like a temporary blip than an ongoing catastrophe. Tesla is something of an outlier with its recent slump—most automakers saw greater than 50% growth in the first quarter of this year. (Bloomberg)

This visualization shows just how dominant China is in the EV supply chain, from mining materials like graphite to manufacturing battery cells. (Cipher News)

Climate change is coming for our summer oysters. The variety that have been bred to be eaten year round are sensitive to extreme heat, making their future rocky. (The Atlantic)

The US has new federal guidelines for carbon offsets. It’s an effort to fix up an industry that studies and reports have consistently shown doesn’t work very well. (New York Times)

The most stubborn myth about heat pumps is that they don’t work in cold weather. Heat pumps are actually more efficient than gas furnaces in cold conditions. (Wired)

AI is an energy hog. This is what it means for climate change.

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

Tech companies keep finding new ways to bring AI into every facet of our lives. AI has taken over my search engine results, and new virtual assistants from Google and OpenAI announced last week are bringing the world eerily close to the 2013 film Her (in more ways than one).

As AI has become more integrated into our world, I’ve gotten a lot of questions about the technology’s rising electricity demand. You may have seen the headlines proclaiming that AI uses as much electricity as small countries, that it’ll usher in a fossil-fuel resurgence, and that it’s already challenging the grid.  

So how worried should we be about AI’s electricity demands? Well, it’s complicated. 

Using AI for certain tasks can come with a significant energy price tag. With some powerful AI models, generating an image can require as much energy as charging up your phone, as my colleague Melissa Heikkilä explained in a story from December. Create 1,000 images with a model like Stable Diffusion XL, and you’ve produced as much carbon dioxide as driving just over four miles in a gas-powered car, according to the researchers Melissa spoke to. 

But while generated images are splashy, there are plenty of AI tasks that don’t use as much energy. For example, creating images is thousands of times more energy-intensive than generating text. And using a smaller model that’s tailored to a specific task, rather than a massive, all-purpose generative model, can be dozens of times more efficient. In any case, generative AI models require energy, and we’re using them a lot. 

Electricity consumption from data centers, AI, and cryptocurrency could reach double 2022 levels by 2026, according to projections from the International Energy Agency. Those technologies together made up roughly 2% of global electricity demand in 2022. Note that these numbers aren’t just for AI—it’s tricky to nail down AI’s specific contribution, so keep that in mind when you see predictions about electricity demand from data centers. 

There’s a wide range of uncertainty in the IEA’s projections, depending on factors like how quickly deployment increases and how efficient computing processes get. On the low end, the sector could require about 160 terawatt-hours of additional electricity by 2026. On the higher end, that number might be 590 TWh. As the report puts it, AI, data centers, and cryptocurrency together are likely adding “at least one Sweden or at most one Germany” to global electricity demand. 

In total, the IEA projects, the world will add about 3,500 TWh of electricity demand over that same period—so while computing is certainly part of the demand crunch, it’s far from the whole story. Electric vehicles and the industrial sector will both be bigger sources of growth in electricity demand than data centers in the European Union, for example. 

Still, some big tech companies are suggesting that AI could get in the way of their climate goals. Microsoft pledged four years ago to bring its greenhouse-gas emissions to zero (or even lower) by the end of the decade. But the company’s recent sustainability report shows that instead, emissions are still ticking up, and some executives point to AI as a reason. “In 2020, we unveiled what we called our carbon moonshot. That was before the explosion in artificial intelligence,” Brad Smith, Microsoft’s president, told Bloomberg Green.

What I found interesting, though, is that it’s not AI’s electricity demand that’s contributing to Microsoft’s rising emissions, at least on paper. The company has agreements in place and buys renewable-energy credits so that electricity needs for all its functions (including AI) are met with renewables. (How much these credits actually help is questionable, but that’s a story for another day.) 

Instead, infrastructure growth could be adding to the uptick in emissions. Microsoft plans to spend $50 billion between July 2023 and June 2024 on expanding data centers to meet demand for AI products, according to the Bloomberg story. Building those data centers requires materials that can be carbon intensive, like steel, cement, and of course chips. 

Some important context to consider in the panic over AI’s energy demand is that while the technology is new, this sort of concern isn’t, as Robinson Meyer laid out in an April story in Heatmap.

Meyer points to estimates from 1999 that information technologies were already accounting for up to 13% of US power demand, and that personal computers and the internet could eat up half the grid’s capacity within the decade. That didn’t end up happening, and even at the time, computing was actually accounting for something like 3% of electricity demand. 

We’ll have to wait and see if doomsday predictions about AI’s energy demand play out. The way I see it, though, AI is probably going to be a small piece of a much bigger story. Ultimately, rising electricity demand from AI is in some ways no different from rising demand from EVs, heat pumps, or factory growth. It’s really how we meet that demand that matters. 

If we build more fossil-fuel plants to meet our growing electricity demand, it’ll come with negative consequences for the climate. But if we use rising electricity demand as a catalyst to lean harder into renewable energy and other low-carbon power sources, and push AI to get more efficient, doing more with less energy, then we can continue to slowly clean up the grid, even as AI continues to expand its reach in our lives. 


Now read the rest of The Spark

Related reading

Check out my colleague Melissa’s story on the carbon footprint of AI from December here

For a closer look at Microsoft’s new sustainability report and the effects of AI, give this Bloomberg Green story from reporters Akshat Rathi and Dina Bass a read. 

Robinson Meyer at Heatmap dug into the context around the AI energy demand in this April piece

Another thing

Missed our event last week on thermal batteries? Good news—the recording is now available for subscribers!

For the latest in our Roundtables series, I spoke with Amy Nordrum, MIT Technology Review executive editor, about how the technology works, who the crucial players are, and what I’m watching for next. Check it out here

Keeping up with climate  

Changing how we generate heat in industry will be crucial to cleaning up that sector in China, according to a new report. Thermal batteries and heat pumps could meet most of the demand. (Axios)

Form Energy is known for its iron-air batteries, which could help unlock cheap energy storage on the grid. Now, the company is working on research to produce green iron. (Canary Media)

The NET Power pilot in Texas is working to generate electricity with natural gas while capturing the vast majority of emissions. But carbon capture technology in power plants is far from proven. (Cipher News)

MIT spinoff Electrified Thermal Solutions is working to bring its thermal battery technology to commercial use. The company’s product is roughly the size of an elevator and can reach temperatures up to 1,800 °C. (Inside Climate News)

Mexico City has seen constant struggles over water. Now groundwater is drying up, and a system of dams and canals may soon be unable to provide water to the city. (New York Times)

Sodium-ion batteries could offer cheap energy storage while avoiding material crunches for metals like lithium, nickel, and cobalt. China has a massive head start, leaving other countries scrambling to catch up. (Latitude Media)

→ Here’s how this abundant material could unlock cheaper energy storage. (MIT Technology Review)

Biochar is made by heating up biomass like wood and plants in low-oxygen environments. It’s a simple approach to carbon removal, but it doesn’t always get as much attention as other carbon removal technologies. (Heatmap)

This startup wants ships to capture their own emissions by bubbling exhaust through seawater and limestone and dumping it into the ocean. Experts caution that some components of the exhaust could harm sea life if they’re not handled properly. (New Scientist)

Last summer was the hottest in 2,000 years. Here’s how we know.

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

I’m ready for summer, but if this year is anything like last year, it’s going to be a doozy. In fact, the summer of 2023 in the Northern Hemisphere was the hottest in over 2,000 years, according to a new study released this week. 

If you’ve been following the headlines, you probably already know that last year was a hot one. But I was gobsmacked by this paper’s title when it came across my desk. The warmest in 2,000 years—how do we even know that?

There weren’t exactly thermometers around in the year 1, so scientists have to get creative when it comes to comparing our climate today with that of centuries, or even millennia, ago. Here’s how our world stacks up against the climate of the past, how we know, and why it matters for our future. 

Today, there are thousands and thousands of weather stations around the globe, tracking the temperature from Death Valley to Mount Everest. So there’s plenty of data to show that 2023 was, in a word, a scorcher. 

Daily global ocean temperatures were the warmest ever recorded for over a year straight. Levels of sea ice hit new lows. And of course, the year saw the highest global average temperatures since record-keeping began in 1850.  

But scientists decided to look even further back into the past for a year that could compare to our current temperatures. To do so, they turned to trees, which can act as low-tech weather stations.

The concentric rings inside a tree are evidence of the plant’s yearly growth cycles. Lighter colors correspond to quick growth over the spring and summer, while the darker rings correspond to the fall and winter. Count the pairs of light and dark rings, and you can tell how many years a tree has lived. 

Trees tend to grow faster during warm, wet years and slower during colder ones. So scientists can not only count the rings but measure their thickness, and use that as a gauge for how warm any particular year was. They also look at factors like density and track different chemical signatures found inside the wood. You don’t even need to cut down a tree to get its help with climatic studies—you can just drill out a small cylinder from the tree’s center, called a core, and study the patterns.

The oldest living trees allow us to peek a few centuries into the past. Beyond that, it’s a matter of cross-referencing the patterns on dead trees with living ones, extending the record back in time like putting a puzzle together. 

It’s taken several decades of work and hundreds of scientists to develop the records that researchers used for this new paper, said Max Torbenson, one of the authors of the study, on a press call. There are over 10,000 trees from nine regions across the Northern Hemisphere represented, allowing the researchers to draw conclusions about individual years over the past two millennia. The year 246 CE once held the crown for the warmest summer in the Northern Hemisphere in the last 2,000 years. But 25 of the last 28 years have beat that record, Torbenson says, and 2023’s summer tops them all. 

These conclusions are limited to the Northern Hemisphere, since there are only a few tree ring records from the Southern Hemisphere, says Jan Esper, lead author of the new study. And using tree rings doesn’t work very well for the tropics because seasons look different there, he adds. Since there’s no winter, there’s usually not as reliable an alternating pattern in tropical tree rings, though some trees do have annual rings that track the wet and dry periods of the year. 

Paleoclimatologists, who study ancient climates, can use other methods to get a general idea of what the climate looked like even earlier—tens of thousands to millions of years ago. 

The biggest difference between the new study using tree rings and methods of looking back further into the past is the precision. Scientists can, with reasonable certainty, use tree rings to draw conclusions about individual years in the Northern Hemisphere (536 CE was the coldest, for instance, likely because of volcanic activity). Any information from further back than the past couple of thousand years will be more of a general trend than a specific data point representing a single year. But those records can still be very useful. 

The oldest glaciers on the planet are at least a million years old, and scientists can drill down into the ice for samples. By examining the ratio of gases like oxygen, carbon dioxide, and nitrogen inside these ice cores, researchers can figure out the temperature of the time corresponding to the layers in the glacier. The oldest continuous ice-core record, which was collected in Antarctica, goes back about 800,000 years. 

Researchers can use fossils to look even further back into Earth’s temperature record. For one 2020 study, researchers drilled into the seabed and looked at the sediment and tiny preserved shells of ancient organisms. From the chemical signatures in those samples, they found that the temperatures we might be on track to record may be hotter than anything the planet has experienced on a global scale in tens of millions of years. 

It’s a bit sobering to know that we’re changing the planet in such a dramatic way. 

The good news is, we know what we need to do to turn things around: cut emissions of planet-warming gases like carbon dioxide and methane. The longer we wait, the more expensive and difficult it will be to stop warming and reverse it, as Esper said on the press call: “We should do as much as possible, as soon as possible.” 


Now read the rest of The Spark

Related reading

Last year broke all sorts of climate records, from emissions to ocean temperatures. For more on the data, check out this story from December.

How hot is too hot for the human body? I tackled that very question in a 2021 story.  

Two engineers in lab coats monitor the thermal battery powering a conveyor belt of bottles

SIMON LANDREIN

Another thing

Readers chose thermal batteries as the 11th Breakthrough Technology of 2024. If you want to hear more about what thermal batteries are, how they work, and why this all matters, join us for the latest in our Roundtables series of online events, where I’ll be getting into the nitty-gritty details and answering some audience questions.

This event is exclusively for subscribers, so subscribe if you haven’t already, and then register here to join us tomorrow, May 16, at noon Eastern time. Hope to see you there! 

Keeping up with climate  

Scientists just recorded the largest ever annual leap in the amount of carbon dioxide in the atmosphere. The concentration of the planet-warming gas in March 2024 was 4.7 parts per million higher than it was a year before. (The Guardian)

Tesla has reportedly begun rehiring some of the workers who were laid off from its charging team in recent weeks. (Bloomberg)

→ To catch up on what’s going on at Tesla, and what it means for the future of EV charging and climate tech more broadly, check out the newsletter from last week if you missed it. (MIT Technology Review)

A new rule could spur thousands of miles of new power lines, making it easier to add renewables to the grid in the US. The Federal Energy Regulatory Commission will require grid operators to plan 20 years ahead, considering things like the speed of wind and solar installations. (New York Times)

Where does carbon dioxide go after it’s been vacuumed out of the atmosphere? Here are 10 options. (Latitude Media)

Ocean temperatures have been extremely high, shattering records over the past year. All that heat could help fuel a particularly busy upcoming hurricane season. (E&E News)

New tariffs in the US will tack on additional costs to a wide range of Chinese imports, including batteries and solar cells. The tariff on EVs will take a particularly drastic jump, going from 27.5% to 102.5%. (Associated Press)

A reporter took a trip to the Beijing Auto Show and drove dozens of EVs. His conclusion? Chinese EVs are advancing much faster than Western automakers can keep up with. (InsideEVs)

Harnessing solar power via satellites in space and beaming it down to Earth is a tempting dream. But the reality, as you might expect, is probably not so rosy. (IEEE Spectrum)

Why EV charging needs more than Tesla

This article is from The Spark, MIT Technology Review’s weekly climate newsletter. To receive it in your inbox every Wednesday, sign up here.

Tesla, the world’s largest EV maker, laid off its entire charging team last week. 

The timing of this move is absolutely baffling. We desperately need many more EV chargers to come online as quickly as possible, and Tesla has been a charging powerhouse. It’s in the midst of opening its charging network to other automakers and establishing its technology as the de facto standard in the US. Now, we’re already seeing new Supercharger sites canceled because of this move. 

The charging meltdown at Tesla could slow progress on EVs overall, and ultimately, the whole situation shows why climate technology needs a whole lot more than Tesla. 

Tesla first unveiled the Supercharger network in 2012 with six locations in the western US. As of 2024, the company operates over 50,000 Superchargers worldwide. (By the way, I want to note that I briefly interned at Tesla in 2016. I don’t have any ties to or financial interest in the company today.) 

The Supercharger network helped make Tesla an EV juggernaut. Fast charging speeds and a navigation system that took the guesswork out of finding charging stations helped ease the transition for people buying their first EVs. Tesla operates more fast chargers than anyone else in the US, and the reliability of those chargers is leagues better than that of competitors. For a long time, this was all exclusive to Tesla drivers. 

Over the past year, Tesla has begun cracking open the doors to its charging network. The company made some of its stations available to all EVs, in part to go after incentives designated for private companies building public chargers. 

In the US, Tesla has also persuaded other automakers to adopt its charging connector, which it standardized and named the North American Charging Standard. In May 2023, Ford announced a move to adopt the NACS, and nearly every other automaker selling EVs in the US has followed suit.

Then, last week, Tesla laid off its 500-person charging team. The move came as part of wider layoffs that are expected to affect 10% of Tesla’s global workforce. Even interns weren’t immune.

Tesla “still plans to grow the Supercharger network,” though the focus will shift to maintaining and expanding existing locations rather than adding new ones, according to a post from CEO Elon Musk on the site formerly known as Twitter. (How does the company plan to expand or even maintain existing locations with apparently no dedicated charging team? Your guess is as good as mine. Tesla didn’t respond to a request for comment.)

But the effects from losing the charging team were immediate. Tesla backed out of a handful of leases for upcoming Supercharger locations in New York. In an email, the company told suppliers to hold off on breaking ground on new construction projects. 

The move is a concerning one at a crucial time for EV charging infrastructure. Right now, there are nowhere near enough chargers installed in the US to support a shift to electric vehicles. If EVs make up half of new-car sales by the end of the decade, we’ll need roughly 1.2 million public chargers installed by then, according to a 2023 study from the National Renewable Energy Laboratory. Today, the country has 170,000 charging ports available. 

In a recent poll, nearly 80% of US adults said that a lack of charging infrastructure is a primary reason for not buying an EV. That was true whether they lived in a city, in the suburbs, or in more rural areas.

In a way, it does make sense that Tesla appears to be uninterested in being the one to build out a public charging network. Chargers are costly to build and maintain, and they might not be all that profitable in the near term

According to analysis by BNEF, Tesla pulled in about $1.7 billion from charging last year, only about 1.5% of the company’s total revenue. Opening up chargers to vehicles from other automakers could help push revenue from this source up to $7.4 billion annually by the end of the decade. But that’s still a relatively small piece of Tesla’s total potential pie. 

Musk seems more interested in pursuing buzzy ideas like robotaxis than doing the difficult and expensive work of providing EV charging as a public service. 

Honestly, I think this move is a wake-up call for the EV industry. Tesla has played an undeniable role in bringing EVs to the mainstream. But we’re in a new stage of the game now, one that’s less about sleek sports cars and more about deploying known technologies and keeping them working. 

Other companies may step in to help fill the charging gap Tesla is opening. Revel expressed interest in taking over those canceled leases in New York City, for instance. But I wouldn’t hold my breath for a shiny new company to be our charging hero. 

Cutting emissions and remaking our economy will require buckling down to deploy and maintain solutions that we already know work, whether that’s in transportation or any other sector. For EV charging, and for climate technology as a whole, we need more than Tesla. Here’s hoping we can get it. 


Now read the rest of The Spark

Related reading

Perhaps the single biggest remaining barrier to EV adoption is a lack of charging infrastructure, as I wrote in a newsletter last year.

We need way more chargers to support the number of new EVs that are expected to hit the roads this decade. I dug into how many for a news story last year.

New battery technology could help EV batteries charge even faster. Learn what could be coming next in this story from August.

Another thing

Meat is a major climate problem. Whether solutions come in the form of plant-based alternatives or products grown in the lab, we shouldn’t expect them to solve every problem under the sun, argues my colleague James Temple, in a new essay published this week. Give it a read! 

Keeping up with climate  

Alternative jet fuels have a corn problem. The crop can be used to make fuels that qualify for tax credits in the US, but critics are skeptical about just how helpful they’ll be in efforts to cut emissions. (MIT Technology Review)

This startup is making fuel from carbon dioxide. Infinium’s Texas facility came online in late 2023, and its synthetic fuels could help clean up aviation and trucking—but only if the price is right. (Bloomberg)

New York City pizza shops are going electric. A citywide ordinance just went into effect that requires wood- and coal-burning ovens to cut their pollution, and many are turning to electric ovens instead of undertaking the costly upgrade. (New York Times)

Building a new energy system happens one project at a time. I loved this list of 10 potentially make-or-break projects that represent the potential future of our grid. (Heatmap)

→ The list includes a new site from Fervo in Utah, expected in 2026. Get the inside look at the company’s technology in this feature story from last year. (MIT Technology Review)

Funding for climate-tech startups in Africa is growing, with businesses raising more than $3.4 billion since 2019. But there’s still a long way to go to help the continent meet its climate goals. (Associated Press)

One very big, and very simple, thing is holding back heat pumps: a lack of workers. We need more people to make and install the appliances, which help cut emissions by using electricity to efficiently heat and cool spaces. (Wired)

→ Heat pumps are booming, and they’re on our list of 2024 Breakthrough Technologies. (MIT Technology Review)

Compressing air and storing it underground could help clean up the grid. Yes, really. Canadian company Hydrostor is close to breaking ground on its first large long-duration energy storage project later this year in Australia. (Inside Climate News)