Why the world doesn’t recycle more nuclear waste

The prospect of making trash useful is always fascinating to me. Whether it’s used batteries, solar panels, or spent nuclear fuel, getting use out of something destined for disposal sounds like a win all around.

In nuclear energy, figuring out what to do with waste has always been a challenge, since the material needs to be dealt with carefully. In a new story, I dug into the question of what advanced nuclear reactors will mean for spent fuel waste. New coolants, fuels, and logistics popping up in companies’ designs could require some adjustments.

My reporting also helped answer another question that was lingering in my brain: Why doesn’t the world recycle more nuclear waste?

There’s still a lot of usable uranium in spent nuclear fuel when it’s pulled out of reactors. Getting more use out of the spent fuel could cut down on both waste and the need to mine new material, but the process is costly, complicated, and not 100% effective.

France has the largest and most established reprocessing program in the world today. The La Hague plant in northern France has the capacity to reprocess about 1,700 tons of spent fuel each year.

The plant uses a process called PUREX—spent fuel is dissolved in acid and goes through chemical processing to pull out the uranium and plutonium, which are then separated. The plutonium is used to make mixed oxide (or MOX) fuel, which can be used in a mixture to fuel conventional nuclear reactors or alone as fuel in some specialized designs. And the uranium can go on to be re-enriched and used in standard low-enriched uranium fuel.

Reprocessing can cut down on the total volume of high-level nuclear waste that needs special handling, says Allison Macfarlane, director of the school of public policy and global affairs at the University of British Columbia and a former chair of the NRC.

But there’s a bit of a catch. Today, the gold standard for permanent nuclear waste storage is a geological repository, a deep underground storage facility. Heat, not volume, is often the key limiting factor for how much material can be socked away in those facilities, depending on the specific repository. And spent MOX fuel gives off much more heat than conventional spent fuel, Macfarlane says. So even if there’s a smaller volume, the material might take up as much, or even more, space in a repository. 

It’s also tricky to make this a true loop: The uranium that’s produced from reprocessing is contaminated with isotopes that can be difficult to separate, Macfarlane says. Today, France essentially saves the uranium for possible future enrichment as a sort of strategic stockpile. (Historically, it’s also exported some to Russia for enrichment.) And while MOX fuel can be used in some reactors, once it is spent, it is technically challenging to reprocess. So today, the best case is that fuel could be used twice, not infinitely.

“Every responsible analyst understands that no matter what, no matter how good your recycling process is, you’re still going to need a geological repository in the end,” says Edwin Lyman, director of nuclear power safety at the Union of Concerned Scientists.

Reprocessing also has its downsides, Lyman adds. One risk comes from the plutonium made in the process, which can be used in nuclear weapons. France handles that risk with high security, and by quickly turning that plutonium into the MOX fuel product.

Reprocessing is also quite expensive, and uranium supply isn’t meaningfully limited. “There’s no economic benefit to reprocessing at this time,” says Paul Dickman, a former Department of Energy and NRC official.

France bears the higher cost that comes with reprocessing largely for political reasons, he says. The country doesn’t have uranium resources, importing its supply today. Reprocessing helps ensure its energy independence: “They’re willing to pay a national security premium.”

Japan is currently constructing a spent-fuel reprocessing facility, though delays have plagued the project, which started construction in 1993 and was originally supposed to start up by 1997. Now the facility is expected to open by 2027.

It’s possible that new technologies could make reprocessing more appealing, and agencies like the Department of Energy should do longer-term research on advanced separation technologies, Dickman says. Some companies working on advanced reactors say they plan to use alternative reprocessing methods in their fuel cycle.

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Brutal times for the US battery industry

Just a few years ago, the battery industry was hot, hot, hot. There was a seemingly infinite number of companies popping up, with shiny new chemistries and massive fundraising rounds. My biggest problem was sifting through the pile to pick the most exciting news to cover.

That tide has turned, and in 2026, what seems to be in unlimited supply isn’t battery success stories but stumbles or straight-up implosions. Companies are failing, investors are pulling back, and batteries, especially for EVs, aren’t looking so hot anymore. On Monday, Steve Levine at The Information (paywalled link) reported that 24M Technologies, a battery company founded in 2010, was shutting down and would auction off its property.

The company itself has been silent, but this is the latest in a string of bad signs, and it’s a big one—at one point 24M was worth over $1 billion, and the company’s innovations could have worked with existing technology. So where does that leave the battery industry?

Many buzzy battery startups in recent years have been trying to sell some new, innovative chemistry to compete with lithium-ion batteries, the status quo that powers phones, laptops, electric vehicles, and even grid storage arrays today. Think sodium-ion batteries and solid-state cells.

24M wasn’t trying to sell a departure from lithium-ion but improvements that could work with the tech. One of the company’s major innovations was its manufacturing process, which involved essentially smearing materials onto sheets of metal to form the electrodes, a simpler and potentially cheaper technique than the standard one. 

The layers in the company’s batteries were thicker, which cut down on some of the inactive materials in cells and improved the energy density. That allows more energy to be stored in a smaller package, boosting the range of EVs—the company famously had a goal of a 1,000-mile battery (about 1,600 kilometers).

We’re still thin on details of what exactly went down at 24M and what comes next for its tech. The company didn’t get back to my questions sent to the official press email, and nobody picked up the phone when I called. 24M cofounder and MIT professor Yet-Ming Chiang declined to speak on the record.

For those who have been closely following the battery industry, more bad news isn’t too surprising. It feels as if everyone is short on money these days, and as purse strings tighten, there’s less interest in novel ideas. “It just feels like there’s not a lot of appetite for innovation,” says Kara Rodby, a technical principal at Volta Energy Technologies, a venture capital firm that focuses on the energy storage industry.

Natron Energy, one of the leading sodium-ion startups in the US, shut down operations in September last year. Ample, an EV battery-swapping company, filed for bankruptcy in December 2025.  

There were always going to be failures from the recent battery boom. Money was flowing to all sorts of companies, some pitching truly wild ideas. But what recent months have made clear is that the battery market is turning brutal, even for the relatively safe bets.

Because 24M’s technology was designed to work into existing lithium-ion chemistry, it could have been an attractive candidate for existing battery companies to license or even acquire. “It’s a great example of something that should have been easier,” Rodby says.  

The gutting of major components of the Inflation Reduction Act, key legislation in the US that provided funding and incentives for batteries and EVs, certainly hasn’t helped. The EV market in the US is cooling off, with automakers canceling EV models and slashing factory plans.

There are bright spots. China’s battery industry is thriving, and its battery and EV giants are looking ever more dominant. The market for stationary energy storage is also still seeing positive signs of growth, even in the US. 

But overall, it’s not looking great. 

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How much wildfire prevention is too much?

The race to prevent the worst wildfires has been an increasingly high-tech one. Companies are proposing AI fire detection systems and drones that can stamp out early blazes. And now, one Canadian startup says it’s going after lightning.

Lightning-sparked fires can be a big deal: The Canadian wildfires of 2023 generated nearly 500 million metric tons of carbon emissions, and lightning-started fires burned 93% of the area affected. Skyward Wildfire claims that it can stop wildfires before they even start by preventing lightning strikes.

It’s a wild promise, and one that my colleague James Temple dug into for his most recent story. (You should read the whole thing; there’s a ton of fascinating history and quirky science.) As James points out in his story, there’s plenty of uncertainty about just how well this would work and under what conditions. But I was left with another lingering question: If we can prevent lightning-sparked fires, should we?

I can’t help myself, so let’s take just a moment to talk about how this lightning prevention method supposedly works. Basically, lightning is static discharge—virtually the same thing as when you rub your socks on a carpet and then touch a doorknob, as James puts it.

When you shuffle across a rug, the friction causes electrons to jump around, so ions build up and an electric field forms. In the case of lightning, it’s snowflakes and tiny ice pellets called graupel rubbing together. They get separated by updrafts, building up a charge difference, and eventually cause an electrostatic discharge—lightning.

Starting in about the 1950s, researchers started to wonder if they might be able to prevent lightning strikes. Some came up with the idea of using metallic chaff, fiberglass strands coated with aluminum. (The military was already using the material to disrupt radar signals.) The idea is that the chaff can act as a conductor, reducing the buildup of static electricity that would otherwise result in a lightning strike.

The theory is sound enough, but results to date have been mixed. Some research suggests you might need high concentrations of chaff to prevent lightning effectively. Some of the early studies that tested the technique were small. And there’s not much information available from Skyward Wildfire about its efforts, as the company hasn’t released data from field trials or published any peer-reviewed papers that we could find. 

Even if this method really can work to stop lightning, should we use it?

Lightning-caused fires could be a growing problem with climate change. Some research has shown that they have substantially increased in the Arctic boreal region, where the planet is warming fastest.

But fire isn’t an inherently bad thing—many ecosystems evolved to burn. Some of the worst wildfires we see today result from a combination of climate-fueled conditions with policies that have allowed fuel to build up so that when fires do start, they burn out of control.

Some experts agree that techniques like Skyward’s would need to be used judiciously. “So even if we have all of the technical skills to prevent lightning-ignited wildfires, there really still needs to be work on when/where to prevent fires so we don’t exacerbate the fuel accumulation problem,” said Phillip Stepanian, a technical staff member at MIT Lincoln Laboratory’s air traffic control and weather systems group, in an email to James.

We also know that practices like prescribed burns can do a lot to reduce the risk of extreme fires—if we allow them and pay for them.

The company says it wouldn’t aim to stop all lightning or all wildfires. “We do not intend to eliminate all wildfires and support prescribed and cultural burning, natural fire regimes, and proactive forest management,” said Nicholas Harterre, who oversees government partnerships at Skyward, in an email to James. Rather, the company aims to reduce the likelihood of ignition on a limited number of extreme-risk days, Harterre said.

Some early responses to this story say that technological fixes for fires are missing the point entirely. Many such solutions “fundamentally misunderstand the problem,” as Daniel Swain, a climate scientist at the University of California Agriculture and Natural Resources, put it in a comment about the story on LinkedIn. That problem isn’t the existence of fire, Swain continues, but its increasing intensity, and its intersection with society because of human-caused factors. “Preventing ignitions doesn’t actually address any of the causes of increasingly destructive wildfires,” he adds.

It’s hard to imagine that exploring more firefighting tools is a bad idea. But to me it seems both essential and quite difficult to suss out which techniques are worth deploying, and how they could be used without putting us in even more potential danger. 

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This company claims a battery breakthrough. Now they need to prove it.

When a company claims to have created what’s essentially the holy grail of batteries, there are bound to be some questions.

Interest has been swirling since Donut Lab, a Finnish company, announced last month that it had a new solid-state battery technology, one that was ready for large-scale production. The company said its batteries can charge super-fast and have a high energy density that would translate to ultra-long-range EVs. What’s more, it claimed the cells can operate safely in the extreme heat and cold, contain “green and abundant materials,” and would cost less than lithium-ion batteries do today.

It sounded amazing—this sort of technology could transform the EV industry. But many quickly wondered if it was all too good to be true. Now, Donut Lab is releasing a series of videos that it says will prove its technology has the secret sauce. Let’s dig into why this company is making news, why many experts are skeptical, and what it all means for the battery industry right now.

Solid-state batteries could deliver the next generation of EVs. In place of a liquid electrolyte (the material that ions move through inside a battery), the cells use a solid material, so they can be more compact. That means a significantly longer range, which could get more people excited to drive EVs.

The problem is, getting these batteries to work and making them at the large scale required for the EV industry hasn’t been a simple task. Some of the world’s most powerful automakers and battery companies have been trying for years to get the technology off the ground. (Toyota at one point said it would have solid-state batteries in cars by 2020. Now it’s shooting for 2027 or 2028.)

While it’s been a long time coming, it does feel as if solid-state batteries are closer than ever. Much of the progress so far has been on semi-solid-state batteries, which use materials like gels for electrolytes. But some companies, including several in China, are getting closer to true solid state. The world’s largest battery company, CATL, plans to manufacture small quantities in 2027. Another major Chinese automaker, Changan, plans to start testing installation of all-solid-state batteries in vehicles this year, with mass production expected to begin next year.

Still, Donut Lab surprised the battery industry when, in a video released in early January ahead of the Consumer Electronics Show in Las Vegas, the company claimed it would put the world’s first all-solid-state battery into production vehicles.

One of the splashiest claims in the announcement was that cells would have an energy density of 400 watt-hours per kilogram (the top commercial lithium-ion batteries today sit at about 250 to 300 Wh/kg). It was also claimed that the cells could charge in as little as five minutes, last 100,000 cycles, and retain 99% of capacity at high and low temperatures—while costing less than lithium-ion cells and being made from “100% green and abundant materials with global availability.”

Many experts were immediately skeptical. “In the solid-state field, the technical barriers are very high,” said Shirley Meng, a professor of molecular engineering at the University of Chicago, when I spoke with her last month. She’d recently attended CES and visited Donut Lab’s booth. “They had zero demo, so I don’t believe it,” she says. “Call me conservative, but I would rather be careful than be sorry later.”

“It’s one of those things where nobody knows—they’ve never heard of it,” said Eric Wachsman, a professor at the University of Maryland and cofounder of the solid-state battery company Ion Storage Systems, in a January interview. “They came out of nowhere.”

Donut Lab has shared very little about what, exactly, this technology might be. It’s not uncommon for battery companies (or any startup, for that matter) to be quiet about technical details before they can get patents filed to protect their technology. But the combination of claims didn’t seem to line up with any known chemistries, leaving experts speculating and, in many cases, doubting Donut Lab’s claims.

“All the parameters are contradictory,” said Yang Hongxin, chairman and CEO of the Chinese battery giant Svolt Energy, in remarks to news outlets in January. For example, there’s often a trade-off between high energy density, which requires thicker electrodes that can store more energy, and fast charging, which requires ions to move quickly through cells. High-performance batteries are also expected to be costly, but Donut Lab claims its technology will be cheaper than lithium-ion technology. 

In a new video released last week, Donut Lab cofounder and CEO Marko Lehtimäki announced the company would be releasing a video series, called “I Donut Believe,” that would provide evidence for their claims. As a header on the accompanying website reads: “Fair enough. Here you go.”

When the website went up last week, it included a countdown timer to Monday February 23, when the company released results from its first third-party testing: a fast charging test. The test showed that a single cell could charge from 0% to 80% capacity in about four and a half minutes—incredibly quick and quite impressive results. (One potential caveat to note is that the cells heated up quite a bit, so thermal management could be important in designing vehicles that use these batteries.)

Even as we see the first technical test results, I’m still left with a lot of questions. How many cycles could this battery do at this charging speed? Can this same cell meet the company’s other performance claims? (I’ve reached out to Donut Lab several times over the past month, both to the company’s press email and to leadership on LinkedIn, but I haven’t gotten a response yet.)

The company has certainly drummed up a lot of interest and attention with its rollout, and the theatrics aren’t over yet. There’s another countdown timer on Donut Lab’s site, which ends on Monday, March 2.

I’m the first one to get excited about a new battery technology. But there’s a sentiment I’ve seen pop up a lot recently online, and one I can’t get out of my head as I continue to follow this story: “Extraordinary claims require extraordinary proof.”

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The building legal case for global climate justice

The United States and the European Union grew into economic superpowers by committing climate atrocities. They have burned a wildly disproportionate share of the world’s oil and gas, planting carbon time bombs that will detonate first in the poorest, hottest parts of the globe. 

Meanwhile, places like the Solomon Islands and Chad—low-lying or just plain sweltering—have emitted relatively little carbon dioxide, but by dint of their latitude and history, they rank among the countries most vulnerable to the fiercest consequences of global warming. That means increasingly devastating cyclones, heat waves, famines, and floods.

Morally, there’s an ironclad case that the countries or companies responsible for this mess should provide compensation for the homes that will be destroyed, the shorelines that will disappear beneath rising seas, and the lives that will be cut short. By one estimate, the major economies owe a climate debt to the rest of the world approaching $200 trillion in reparations.

Legally, though, the case has been far harder to make. Even putting aside the jurisdictional problems, early climate science couldn’t trace the provenance of airborne molecules of carbon dioxide across oceans and years. Deep-pocketed corporations with top-tier legal teams easily exploited those difficulties. 

Now those tides might be turning. More climate-related lawsuits are getting filed, particularly in the Global South. Governments, nonprofits, and citizens in the most climate-exposed nations continue to test new legal arguments in new courts, and some of those courts are showing a new willingness to put nations and their industries on the hook as a matter of human rights. In addition, the science of figuring out exactly who is to blame for specific weather disasters, and to what degree, is getting better and better. 

It’s true that no court has yet held any climate emitter liable for climate-related damages. For starters, nations are generally immune from lawsuits originating in other countries. That’s why most cases have focused on major carbon producers. But they’ve leaned on a pretty powerful defense. 

While oil and gas companies extract, refine, and sell the world’s fossil fuels, most of the emissions come out of “the vehicles, power plants, and factories that burn the fuel,” as Michael Gerrard and Jessica Wentz, of Columbia Law School’s Sabin Center, note in a recent piece in Nature. In other words, companies just dig the stuff up. It’s not their fault someone else sets it on fire.

So victims of extreme weather events continue to try new legal avenues and approaches, backed by ever-more-convincing science. Plaintiffs in the Philippines recently sued the oil giant Shell over its role in driving Super Typhoon Odette, a 2021 storm that killed more than 400 people and displaced nearly 800,000. The case relies partially on an attribution study that found climate change made extreme rainfall like that seen in Odette twice as likely. 

IVAN JOESEFF GUIWANON/GREENPEACE

Overall, evidence of corporate culpability—linking a specific company’s fossil fuel to a specific disaster—is getting easier to find. For example, a study published in Nature in September was able to determine how much particular companies contributed to a series of 21st-century heat waves.

A number of recent legal decisions signal improving odds for these kinds of suits. Notably, a handful of determinations in climate cases before the European Court of Human Rights affirmed that states have legal obligations to protect people from the effects of climate change. And though it dismissed the case of a Peruvian farmer who sued a German power company over fears that a melting alpine glacier could destroy his property, a German court determined that major carbon polluters could in principle be found liable for climate damages tied to their emissions. 

At least one lawsuit has already emerged that could test that principle: Dozens of Pakistani farmers whose land was deluged during the massive flooding events of 2022 have sued a pair of major German power and cement companies.

Even if the lawsuit fails, that would be a problem with the system, not the science. Major carbon-polluting countries and companies have a disproportionate responsibility for climate-change-powered disasters. 

Wealthy nations continued to encourage business practices that pollute the atmosphere, even as the threat of climate change grew increasingly grave. And oil and gas companies remain the kingpin suppliers to a fossil-fuel-addicted world. They have operated with the full knowledge of the massive social, environmental, and human cost imposed by their business while lobbying fiercely against any rules that would force them to pay for those harms or clean up their act. 

They did it. They knew. In a civil society where rule of law matters, they should pay the price. 

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

Why EVs are gaining ground in Africa

EVs are getting cheaper and more common all over the world. But the technology still faces major challenges in some markets, including many countries in Africa.

Some regions across the continent still have limited grid and charging infrastructure, and those that do have widespread electricity access sometimes face reliability issues—a problem for EV owners, who require a stable electricity source to charge up and get around.

But there are some signs of progress. I just finished up a story about the economic case: A recent study in Nature Energy found that EVs from scooters to minibuses could be cheaper to own than gas-powered vehicles in Africa by 2040.

If there’s one thing to know about EVs in Africa, it’s that each of the 54 countries on the continent faces drastically different needs, challenges, and circumstances. There’s also a wide range of reasons to be optimistic about the prospects for EVs in the near future, including developing policies, a growing grid, and an expansion of local manufacturing.  

Even the world’s leading EV markets fall short of Ethiopia’s aggressively pro-EV policies. In 2024, the country became the first in the world to ban the import of non-electric private vehicles.

The case is largely an economic one: Gasoline is expensive there, and the country commissioned Africa’s largest hydropower dam in September 2025, providing a new source of cheap and abundant clean electricity. The nearly $5 billion project has a five-gigawatt capacity, doubling the grid’s peak power in the country.  

Much of Ethiopia’s vehicle market is for used cars, and some drivers are still opting for older gas-powered vehicles. But this nudge could help increase the market for EVs there.  

Other African countries are also pushing some drivers toward electrification. Rwanda banned new registrations for commercial gas-powered motorbikes in the capital city of Kigali last year, encouraging EVs as an alternative. These motorbike taxis can make up over half the vehicles on the city’s streets, so the move is a major turning point for transportation there. 

Smaller two- and three-wheelers are a bright spot for EVs globally: In 2025, EVs made up about 45% of new sales for such vehicles. (For cars and trucks, the share was about 25%.)

And Africa’s local market is starting to really take off. There’s already some local assembly of electric two-wheelers in countries including Morocco, Kenya, and Rwanda, says Nelson Nsitem, lead Africa energy transition analyst at BloombergNEF, an energy consultancy. 

Spiro, a Dubai-based electric motorbike company, recently raised $100 million in funding to expand operations in Africa. The company currently assembles its bikes in Uganda, Kenya, Nigeria, and Rwanda, and as of October it has over 60,000 bikes deployed and 1,500 battery swap stations operating.

Assembly and manufacturing for larger EVs and batteries is also set to expand. Gotion High-Tech, a Chinese battery company, is currently building Africa’s first battery gigafactory. It’s a $5.6 billion project that could produce 20 gigawatt-hours of batteries annually, starting in 2026. (That’s enough for hundreds of thousands of EVs each year.)

Chinese EV companies are looking to growing markets like Southeast Asia and Africa as they attempt to expand beyond an oversaturated domestic scene. BYD, the world’s largest EV company, is aggressively expanding across South Africa and plans to have as many as 70 dealerships in the country by the end of this year. That will mean more options for people in Africa looking to buy electric. 

“You have very high-quality, very affordable vehicles coming onto the market that are benefiting from the economies of scale in China. These countries stand to benefit from that,” says Kelly Carlin, a manager in the program on carbon-free transportation at the Rocky Mountain Institute, an energy think tank. “It’s a game changer,” he adds.

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Three questions about next-generation nuclear power, answered

Nuclear power continues to be one of the hottest topics in energy today, and in our recent online Roundtables discussion about next-generation nuclear power, hyperscale AI data centers, and the grid, we got dozens of great audience questions.

These ran the gamut, and while we answered quite a few (and I’m keeping some in mind for future reporting), there were a bunch we couldn’t get to, at least not in the depth I would have liked.

So let’s answer a few of your questions about advanced nuclear power. I’ve combined similar ones and edited them for clarity.

How are the fuel needs for next-generation nuclear reactors different, and how are companies addressing the supply chain?

Many next-generation reactors don’t use the low-enriched uranium used in conventional reactors.

It’s worth looking at high-assay low-enriched uranium, or HALEU, specifically. This fuel is enriched to higher concentrations of fissile uranium than conventional nuclear fuel, with a proportion of the isotope U-235 that falls between 5% and 20%. (In conventional fuel, it’s below 5%.)

HALEU can be produced with the same technology as low-enriched uranium, but the geopolitics are complicated. Today, Russia basically has a monopoly on HALEU production. In 2024, the US banned the import of Russian nuclear fuel through 2040 in an effort to reduce dependence on the country. Europe hasn’t taken the same measures, but it is working to move away from Russian energy as well.

That leaves companies in the US and Europe with the major challenge of securing the fuel they need when their regular Russian supply has been cut off or restricted.

The US Department of Energy has a stockpile of HALEU, which the government is doling out to companies to help power demonstration reactions. In the longer term, though, there’s still a major need to set up independent HALEU supply chains to support next-generation reactors.

How is safety being addressed, and what’s happening with nuclear safety regulation in the US?

There are some ways that next-generation nuclear power plants could be safer than conventional reactors. Some use alternative coolants that would prevent the need to run at the high pressure required in conventional water-cooled reactors. Many incorporate passive safety shutoffs, so if there are power supply issues, the reactors shut down harmlessly, avoiding risk of meltdown. (These can be incorporated in newer conventional reactors, too.)

But some experts have raised concerns that in the US, the current administration isn’t taking nuclear safety seriously enough.

A recent NPR investigation found that the Trump administration had secretly rewritten nuclear rules, stripping environmental protections and loosening safety and security measures. The government shared the new rules with companies that are part of a program building experimental nuclear reactors, but not with the public.

I’m reminded of a talk during our EmTech MIT event in November, where Koroush Shirvan, an MIT professor of nuclear engineering, spoke on this issue. “I’ve seen some disturbing trends in recent times, where words like ‘rubber-stamping nuclear projects’ are being said,” Shirvan said during that event.  

During the talk, Shirvan shared statistics showing that nuclear power has a very low rate of injury and death. But that’s not inherent to the technology, and there’s a reason injuries and deaths have been low for nuclear power, he added: “It’s because of stringent regulatory oversight.”  

Are next-generation reactors going to be financially competitive?

Building a nuclear power plant is not cheap. Let’s consider the up-front investment needed to build a power plant.  

Plant Vogtle in Georgia hosts the most recent additions to the US nuclear fleet—Units 3 and 4 came online in 2023 and 2024. Together, they had a capital cost of $15,000 per kilowatt, adjusted for inflation, according to a recent report from the US Department of Energy. (This wonky unit I’m using divides the total cost to build the reactors by their expected power output, so we can compare reactors of different sizes.)

That number’s quite high, partly because those were the first of their kind built in the US, and because there were some inefficiencies in the planning. It’s worth noting that China builds reactors for much less, somewhere between $2,000/kW and $3,000/kW, depending on the estimate.

The up-front capital cost for first-of-a-kind advanced nuclear plants will likely run between $6,000 and $10,000 per kilowatt, according to that DOE report. That could come down by up to 40% after the technologies are scaled up and mass-produced.

So new reactors will (hopefully) be cheaper than the ultra-over-budget and behind-schedule Vogtle project, but they aren’t necessarily significantly cheaper than efficiently built conventional plants, if you normalize by their size.

It’ll certainly be cheaper to build new natural-gas plants (setting aside the likely equipment shortages we’re likely going to see for years.) Today’s most efficient natural-gas plants cost just $1,600/kW on the high end, according to data from Lazard.

An important caveat: Capital cost isn’t everything—running a nuclear plant is relatively inexpensive, which is why there’s so much interest in extending the lifetime of existing plants or reopening shuttered ones.

Ultimately, by many metrics, nuclear plants of any type are going to be more expensive than other sources, like wind and solar power. But they provide something many other power sources don’t: a reliable, stable source of electricity that can run for 60 years or more.

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How the grid can ride out winter storms

The eastern half of the US saw a monster snowstorm over the weekend. The good news is the grid has largely been able to keep up with the freezing temperatures and increased demand. But there were some signs of strain, particularly for fossil-fuel plants.

One analysis found that PJM, the nation’s largest grid operator, saw significant unplanned outages in plants that run on natural gas and coal. Historically, these facilities can struggle in extreme winter weather.

Much of the country continues to face record-low temperatures, and the possibility is looming for even more snow this weekend. What lessons can we take from this storm, and how might we shore up the grid to cope with extreme weather?

Living in New Jersey, I have the honor of being one of the roughly 67 million Americans covered by the PJM Interconnection.

So I was in the thick of things this weekend, when PJM saw unplanned outages of over 20 gigawatts on Sunday during the height of the storm. (That’s about 16% of the grid’s demand that afternoon.) Other plants were able to make up the difference, and thankfully, the power didn’t go out in my area. But that’s a lot of capacity offline.

Typically, the grid operator doesn’t announce details about why an outage occurs until later. But analysts at Energy Innovation, a policy and research firm specializing in energy and climate, went digging. By examining publicly available grid mix data (a breakdown of what types of power plants are supplying the grid), the team came to a big conclusion: Fossil fuels failed during the storm.

The analysts found that gas-fired power plants were producing about 10 gigawatts less power on Sunday than the peak demand on Saturday, even while electricity prices were high. Coal- and oil-burning plants were down too. Because these plants weren’t operating, even when high prices would make it quite lucrative, they were likely a significant part of the problem, says Michelle Solomon, a manager in the electricity program at Energy Innovation.

PJM plans to share more details about the outages at an upcoming committee meeting once the cold snap passes, Dan Lockwood, a PJM spokesperson, told me via email.

Fossil-fuel plants can see reliability challenges during winter: When temperatures drop, pressures in natural-gas lines fall too, which can lead to issues for fuel supply. Freezing temperatures can throw compression stations and other mechanical equipment offline and even freeze piles of coal.

One of the starkest examples came in 2021, when Texas faced freezing temperatures that took many power plants offline and threw the grid into chaos. Many homes lost power for days, and at least 246 people died during that storm.

Texas fared much better this time around. After 2021, the state shored up its grid, adding winter weatherization for power plants and transmission systems. Texas has also seen a huge flood of batteries come online, which has greatly helped the grid during winter demand peaks, especially in the early mornings. Texas was also simply lucky that this storm was less severe there, as one expert told Inside Climate News this week.

Here on the East Coast, we’re not out of the woods yet. The snow has stopped falling, but grids are still facing high electricity demand because of freezing temperatures. (I’ve certainly been living under my heated blanket these last few days.)

PJM could see a peak power demand of 130 gigawatts for seven straight days, a winter streak that the local grid has never experienced, according to an update to the utility’s site on Tuesday morning.

The US Department of Energy issued emergency orders to several grid operators, including PJM, that allow power plants to run while basically ignoring emissions regulations. The department also issued orders allowing several grids to tell data centers and other facilities to begin using backup generators. (This is good news for reliability but bad news for clean air and the climate, since these power sources are often incredibly emissions-intensive.)

We here on the East Coast could learn a thing or two from Texas so we don’t need to resort to these polluting emergency measures to keep the lights on. More energy storage could be a major help in future winter storms, lending flexibility to the grid to help ride out the worst times, Solomon says. Getting offshore wind online could also help, since those facilities typically produce reliable power in the winter. 

No one energy source will solve the massive challenge of building and maintaining a resilient grid. But as we face the continued threat of extreme storms, renewables might actually help us weather them. 

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Why 2026 is a hot year for lithium

In 2026, I’m going to be closely watching the price of lithium.

If you’re not in the habit of obsessively tracking commodity markets, I certainly don’t blame you. (Though the news lately definitely makes the case that minerals can have major implications for global politics and the economy.)

But lithium is worthy of a close look right now.

The metal is crucial for lithium-ion batteries used in phones and laptops, electric vehicles, and large-scale energy storage arrays on the grid. Prices have been on quite the roller coaster over the last few years, and they’re ticking up again after a low period. What happens next could have big implications for mining and battery technology.

Before we look ahead, let’s take a quick trip down memory lane. In 2020, global EV sales started to really take off, driving up demand for the lithium used in their batteries. Because of that growing demand and a limited supply, prices shot up dramatically, with lithium carbonate going from under $10 per kilogram to a high of roughly $70 per kilogram in just two years.

And the tech world took notice. During those high points, there was a ton of interest in developing alternative batteries that didn’t rely on lithium. I was writing about sodium-based batteries, iron-air batteries, and even experimental ones that were made with plastic.

Researchers and startups were also hunting for alternative ways to get lithium, including battery recycling and processing methods like direct lithium extraction (more on this in a moment).

But soon, prices crashed back down to earth. We saw lower-than-expected demand for EVs in the US, and developers ramped up mining and processing to meet demand. Through late 2024 and 2025, lithium carbonate was back around $10 a kilogram again. Avoiding lithium or finding new ways to get it suddenly looked a lot less crucial.

That brings us to today: lithium prices are ticking up again. So far, it’s nowhere close to the dramatic rise we saw a few years ago, but analysts are watching closely. Strong EV growth in China is playing a major role—EVs still make up about 75% of battery demand today. But growth in stationary storage, batteries for the grid, is also contributing to rising demand for lithium in both China and the US.

Higher prices could create new opportunities. The possibilities include alternative battery chemistries, specifically sodium-ion batteries, says Evelina Stoikou, head of battery technologies and supply chains at BloombergNEF. (I’ll note here that we recently named sodium-ion batteries to our 2026 list of 10 Breakthrough Technologies.)

It’s not just batteries, though. Another industry that could see big changes from a lithium price swing: extraction.

Today, most lithium is mined from rocks, largely in Australia, before being shipped to China for processing. There’s a growing effort to process the mineral in other places, though, as countries try to create their own lithium supply chains. Tesla recently confirmed that it’s started production at its lithium refinery in Texas, which broke ground in 2023. We could see more investment in processing plants outside China if prices continue to climb.

This could also be a key year for direct lithium extraction, as Katie Brigham wrote in a recent story for Heatmap. That technology uses chemical or electrochemical processes to extract lithium from brine (salty water that’s usually sourced from salt lakes or underground reservoirs), quickly and cheaply. Companies including Lilac Solutions, Standard Lithium, and Rio Tinto are all making plans or starting construction on commercial facilities this year in the US and Argentina. 

If there’s anything I’ve learned about following batteries and minerals over the past few years, it’s that predicting the future is impossible. But if you’re looking for tea leaves to read, lithium prices deserve a look. 

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

Three climate technologies breaking through in 2026

Happy New Year! I know it’s a bit late to say, but it never quite feels like the year has started until the new edition of our 10 Breakthrough Technologies list comes out. 

For 25 years, MIT Technology Review has put together this package, which highlights the technologies that we think are going to matter in the future. This year’s version has some stars, including gene resurrection (remember all the dire wolf hype last year?) and commercial space stations. 

And of course, the world of climate and energy is represented with sodium-ion batteries, next-generation nuclear, and hyperscale AI data centers. Let’s take a look at what ended up on the list, and what it says about this moment for climate tech. 

Sodium-ion batteries

I’ve been covering sodium-ion batteries for years, but this moment feels like a breakout one for the technology. 

Today, lithium-ion cells power everything from EVs, phones, and computers to huge stationary storage arrays that help support the grid. But researchers and battery companies have been racing to develop an alternative, driven by the relative scarcity of lithium and the metal’s volatile price in recent years. 

Sodium-ion batteries could be that alternative. Sodium is much more abundant than lithium, and it could unlock cheaper batteries that hold a lower fire risk.  

There are limitations here: Sodium-ion batteries won’t be able to pack as much energy into cells as their lithium counterparts. But it might not matter, especially for grid storage and smaller EVs. 

In recent years, we’ve seen a ton of interest in sodium-based batteries, particularly from major companies in China. Now the new technology is starting to make its way into the world—CATL says it started manufacturing these batteries at scale in 2025. 

Next-generation nuclear

Nuclear reactors are an important part of grids around the world today—massive workhorse reactors generate reliable, consistent electricity. But the countries with the oldest and most built-out fleets have struggled to add to them in recent years, since reactors are massive and cost billions. Recent high-profile projects have gone way over budget and faced serious delays. 

Next-generation reactor designs could help the industry break out of the old blueprint and get more nuclear power online more quickly, and they’re starting to get closer to becoming reality. 

There’s a huge variety of proposals when it comes to what’s next for nuclear. Some companies are building smaller reactors, which they say could make it easier to finance new projects, and get them done on time. 

Other companies are focusing on tweaking key technical bits of reactors, using alternative fuels or coolants that help ferry heat out of the reactor core. These changes could help reactors generate electricity more efficiently and safely. 

Kairos Power was the first US company to receive approval to begin construction on a next-generation reactor to produce electricity. China is emerging as a major center of nuclear development, with the country’s national nuclear company reportedly working on several next-gen reactors. 

Hyperscale data centers

This one isn’t quite what I would call a climate technology, but I spent most of last year reporting on the climate and environmental impacts of AI, and the AI boom is deeply intertwined with climate and energy. 

Data centers aren’t new, but we’re seeing a wave of larger centers being proposed and built to support the rise of AI. Some of these facilities require a gigawatt or more of power—that’s like the output of an entire conventional nuclear power plant, just for one data center. 

(This feels like a good time to mention that our Breakthrough Technologies list doesn’t just highlight tech that we think will have a straightforwardly positive influence on the world. I think back to our 2023 list, which included mass-market military drones.)

There’s no denying that new, supersize data centers are an important force driving electricity demand, sparking major public pushback, and emerging as a key bit of our new global infrastructure. 

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