You’re out of free articles.
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
Sign In or Create an Account.
By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
Welcome to Heatmap
Thank you for registering with Heatmap. Climate change is one of the greatest challenges of our lives, a force reshaping our economy, our politics, and our culture. We hope to be your trusted, friendly, and insightful guide to that transformation. Please enjoy your free articles. You can check your profile here .
subscribe to get Unlimited access
Offer for a Heatmap News Unlimited Access subscription; please note that your subscription will renew automatically unless you cancel prior to renewal. Cancellation takes effect at the end of your current billing period. We will let you know in advance of any price changes. Taxes may apply. Offer terms are subject to change.
Subscribe to get unlimited Access
Hey, you are out of free articles but you are only a few clicks away from full access. Subscribe below and take advantage of our introductory offer.
subscribe to get Unlimited access
Offer for a Heatmap News Unlimited Access subscription; please note that your subscription will renew automatically unless you cancel prior to renewal. Cancellation takes effect at the end of your current billing period. We will let you know in advance of any price changes. Taxes may apply. Offer terms are subject to change.
Create Your Account
Please Enter Your Password
Forgot your password?
Please enter the email address you use for your account so we can send you a link to reset your password:
Geothermal is getting closer to the big time. Last week, Fervo Energy — arguably the country’s leading enhanced geothermal company — announced that its Utah demonstration project had achieved record production capacity. The new approach termed “enhanced geothermal,” which borrows drilling techniques and expertise from the oil and gas industry, seems poised to become a big player on America’s clean, 24/7 power grid of the future.
Why is geothermal so hot? How soon could it appear on the grid — and why does it have advantages that other zero-carbon technologies don’t? On this week’s episode of Shift Key, Rob and Jesse speak with a practitioner and an expert in the world of enhanced geothermal. Sarah Jewett is the vice president of strategy at Fervo Energy, which she joined after several years in the oil and gas industry. Wilson Ricks is a doctoral student of mechanical and aerospace engineering at Princeton University, where he studies macro-energy systems modeling. Shift Key is hosted by Robinson Meyer, the founding executive editor of Heatmap, and Jesse Jenkins, a professor of energy systems engineering at Princeton University.
Subscribe to “Shift Key” and find this episode on Apple Podcasts, Spotify, Amazon, or wherever you get your podcasts.
You can also add the show’s RSS feed to your podcast app to follow us directly.
Here is an excerpt from our conversation:
Robinson Meyer: I just wanted to hit a different note here, which is, Sarah, you’ve alluded a few times to your past in the oil and gas industry. I think this is true across Fervo, is that of course, the technologies we’re discussing here are fracking derived. What has your background in the oil and gas industry and hydrocarbons taught you that you think about at Fervo now, and developing geothermal as a resource?
Sarah Jewett: There are so many things. I mean, I’m thinking about my time in the oil and gas industry daily. And you’re exactly right, I think today about 60% of Fervo’s employees come from the oil and gas industry. And because we are only just about to start construction on our first power facility, the percentage of contractors and field workers from the oil and gas industry is much higher than 60%.
Jesse Jenkins: Right, you can’t go and hire a bunch of people with geothermal experience when there is no large-scale geothermal industry to pull from.
Jewett: That’s right. That’s right. And so the oil and gas industry, I think, has taught us, so many different types of things. I mean, we can’t really exist without thinking about the history of the oil and gas industry — even, you know, Wilson and I are sort of comparing our learning rates to learning rates observed in various different oil and gas basins by different operators, so you can see a lot of prior technological pathways.
I mean, first off, we’re just using off the shelf technology that has been proven and tested in the oil and gas industry over the last 25 years, which has been, really, the reason why geothermal is able to have this big new unlock, because we’re using all of this off the shelf technology that now exists. It’s not like the early 2000s, where there was a single bit we could have tried. Now there are a ton of different bits that are available to us that we can try and say, how is this working? How is this working? How’s this working?
So I think, from a technological perspective, it’s helpful. And then from just an industry that has set a solid example it’s been really helpful, and that can be leveraged in a number of different ways. Learning rates, for example; how to set up supply chains in remote areas, for example; how to engage with and interact with communities. I think we’ve seen examples of oil and gas doing that well and doing it poorly. And I’ve gotten to observe firsthand the oil and gas industry doing it well and doing it poorly.
And so I’ve gotten to learn a lot about how we need to treat those around us, explain to them what it is that we’re doing, how open we need to be. And I think that has been immensely helpful as we’ve crafted the role that we’re going to play in these communities at large.
Wilson Ricks: I think it’s also interesting to talk about the connection to the oil and gas industry from the perspective of the political economy of the energy transition, specifically because you hear policymakers talk all the time about retraining workers from these legacy industries that, if we’re serious about decarbonizing, will unavoidably have to contract — and, you know, getting those people involved in clean energy, in these new industries.
And often that’s taking drillers and retraining some kind of very different job — or coal miners — into battery manufacturers. This is almost exactly one to one. Like Sarah said, there’s additional expertise and experience that you need to get really good at doing this in the geothermal context. But for the most part, you are taking the exact same skills and just reapplying them, and so it allows for both a potentially very smooth transition of workforces, and also it allows for scale-up of enhanced geothermal to proceed much more smoothly than it potentially would if you had to kind of train an entire workforce from scratch to just do this.
This episode of Shift Key is sponsored by …
Watershed’s climate data engine helps companies measure and reduce their emissions, turning the data they already have into an audit-ready carbon footprint backed by the latest climate science. Get the sustainability data you need in weeks, not months. Learn more at watershed.com.
As a global leader in PV and ESS solutions, Sungrow invests heavily in research and development, constantly pushing the boundaries of solar and battery inverter technology. Discover why Sungrow is the essential component of the clean energy transition by visiting sungrowpower.com.
Antenna Group helps you connect with customers, policymakers, investors, and strategic partners to influence markets and accelerate adoption. Visit antennagroup.com to learn more.
Music for Shift Key is by Adam Kromelow.
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
On hydrogen woes, Stegra’s steel costs, and refining vs. mining
Current conditions: The Northeastern U.S. is facing winds of up to 80 miles per hour • The remnants of Typhoon Halong are lashing the Alaskan villages of Kipnuk and Kwigillingok with powerful winds and storm surge • A heat wave in South Korea is bringing higher average temperatures this week than in July.
The United States military is stockpiling up to $1 billion of critical minerals as part of a global effort to counter China’s dominance over the metals necessary for sensitive industries including advanced manufacturing and defense. A Financial Times analysis of public filings from the Pentagon’s Defense Logistics Agency showed that the Trump administration has accelerated procurements in recent months as Beijing has cracked down on exports of rare earths and other metals, over which Chinese companies enjoy a tight grip over global supplies. The Department of Defense is “incredibly focused on the stockpile,” a former agency official told the newspaper. “They’re definitely looking for more, and they’re doing it in a deliberate and expansive way, and looking for new sources of different ores needed for defence products.” Among the companies that received funding from the so-called DLA, as I reported last month, is the Ohio-based startup Xerion, whose pioneering method for processing cobalt is now being applied to gallium.
The Trump administration has been on a partial-nationalization spree in recent months to secure mineral supplies. In July, the U.S. military became the largest shareholder in MP Materials, the lone company producing rare earths in the U.S. Last month, the Department of Energy overhauled a loan to Lithium Americas’ Thacker Pass project to take a stake in what will become one of the world’s biggest lithium mines. Earlier this month, President Donald Trump took a share of the Alaskan mining startup Trilogy Metals, as I reported in this newsletter. Reuters reported that the administration is also considering buying shares in Critical Metals, the company looking to develop rare earths in Greenland.
Mega-constulancy McKinsey & Company published a new report on the energy transition Monday, modeling different scenarios for the energy mix of the near-future. None of those scenarios includes clean hydrogen in a significant role. The fuel “is not yet cost competitive at scale, so it is expected to play a limited role in the energy mix,” the report says. Unless governments mandate its use, the analysis found, fuels such as clean hydrogen “are not likely to achieve broad adoption before 2040.” By contrast, fossil fuels are projected to retain between 41% and 55% of the global energy mix by 2050
The report shows hydrogen with a growing but still tiny share of energy usage in 2050.McKinsey
In a sign of where hydrogen may be in its development, another report published Tuesday morning by the California Hydrogen Business Council listed “raising awareness” and “understanding hydrogen” as the first two steps in laying the groundwork for the safe usage of the fuel. The trade group’s 66-page analysis concluded that, while hydrogen “is a hazardous material,” it “can also be used safely” and that “safety should not be viewed as a barrier, but as a catalyst for innovation and acceptance.”
Stegra, the Swedish low-carbon steel startup that aims to use clean hydrogen in its production process, is “scrambling to survive as it struggles to resolve a growing funding gap,” the Financial Times reported Monday. One of Europe’s highest-profile green industrial projects, the company was founded by the same Swedish financiers as the bankrupt battery maker Northvolt. Stegra now needs to raise more than $1.7 billion to build its plant as costs tripled in the past three months, unnamed sources familiar with the financing told the newspaper. Northvolt went under in March despite raising $15 billion in debt, equity, and government funds, signaling how quickly costs can cripple a company’s capacity to continue operating.
While the U.S. steel industry is already cleaner than many countries’ due to its dependence on scrap material rather than iron produced with coal, the Trump administration has slashed funding for green steel, including Cleveland-Cliffs nation-leading effort to produce green steel with clean hydrogen. Yet the “golden share” President Donald Trump claimed for the U.S. Government in U.S. Steel as part of his approval for Japanese rival Nippon Steel’s takeover deal this summer could give a future administration the legal grounds to require the American steelmaker to go green, as Heatmap’s Matthew Zeitlin reported.
Commodities trading giant Trafigura, the world’s largest metals dealer, issued a stark warning to Western countries looking to dig new ores out of the Earth to compete with China. “Mining is not critical,” Trafigura CEO Richard Holtum said in London on Monday, according to Mining Journal. “ True supply chain security comes from processing investment, not just extraction.” China refines roughly 65% of the world’s copper, 70% of its lithium, and 90% of its rare earths. “Western nations are fighting the wrong battle,” Giacomo Prandelli, a commodities trader and analyst, wrote in a post on LinkedIn in response to Holtum’s speech. “They obsess over mining permits while China and Indonesia dominate the midstream, turning raw ore into refined metals that power the global energy transition.”
Investments in refining minerals, however, are costly. While the Pentagon’s purchases of metals guarantees at least one buyer, the Trump administration’s elimination of tax credits for electric vehicles eliminated a key source of demand that would have promised more offtakers for refined metals, representing what Matthew called “the paradox Trump’s critical minerals crusade” back in January.
After raising $78 million in a Series C round last April, sodium-ion battery startup Alsym Energy has rolled out its first battery designed for stationary storage that the company says will be cheaper than lithium-ion systems from day one, Heatmap’s Katie Brigham reported this morning. “I believe we are farthest ahead than anyone else in that space today in the United States,” Alsym’s co-founder and CEO Mukesh Chatter told her. Since the U.S. has vast sodium reserves, Chatter said the company’s America-made batteries will be cheaper than anywhere else. But either way, the company’s cells “will be cost-competitive with the leading lithium-ion chemistry right off the bat,” Katie wrote, with the overall system 30% cheaper because the battery’s thermal stability and ability to perform at high temperatures makes costly cooling systems moot. While sodium-ion cells are less energy dense than lithium-ion, getting rid of the entire HVAC system makes the batteries can operate in “space-constrained environments such as commercial or residential buildings.”
In California, zero-emission vehicles represented 29.1% of new car sales in the third quarter of 2025, the highest quarterly sales ever recorded in the state, Governor Gavin Newsom’s press office announced Monday. “This comes despite the efforts by the Trump administration to derail the ZEV industry and raise the cost of a clean car.” The spike could also be a result of it. Across the country, Americans scrambled to buy electric vehicles at a record clip to secure federal tax credits before the September 30 expiration date set under Trump’s landmark tax law.
After a string of high-profile failures, this sodium-ion startup has a proprietary chemistry and a plan to compete on cost.
It’s been a bad year for batteries. Grand plans to commercialize novel chemistries and build a manufacturing base outside of China have stumbled, with the collapse of both Northvolt and Natron casting a shadow over the sector. But just as many may be losing faith, there’s a new player in the space: Alsym Energy announced today that it’s rolling out a sodium-ion battery designed for stationary storage that it says will be cheaper than lithium-ion systems from day one.
“It’s always the darkest before the sunrise,” Alsym’s co-founder and CEO Mukesh Chatter told me, saying that past failures in the battery space are irrelevant to the specific tech his company is pursuing. The startup, which raised a $78 million Series C round last April, is targeting the battery energy storage market across utility-scale, commercial, and industrial applications — everything from grid-connected systems to power for data centers, high rise buildings, and mining operations.
Alsym’s chemistry is called sodium iron pyrophosphate, or NFPP+. The “plus” represents dopants — small amounts of additional elements — which are added to the chemistry to improve performance. While the specific dopants and the battery’s electrolyte are proprietary, Chatter told me that the technology doesn’t require the critical minerals lithium, cobalt, or nickel, and that the company will source raw materials entirely from the U.S. or its allies.
The product, which is scheduled to deploy on a small scale next year and reach higher volumes in 2027, follows a decade of research into nonflammable lithium-ion alternatives. The company spent years testing different chemistries after it spun out of MIT in 2015, before settling on NFPP+ chemistry within the last 18 months. Chatter remained tight-lipped about the specifics of that process, noting only that the company faced “a couple of false starts,” coupled with supply chain challenges earlier this year.
Now, though, those years of research might have finally paid off. “I believe we are farthest ahead than anyone else in that space today in the United States,” he told me.
One of Alsym’s key advantages, Chatter explained, is that its battery has been certified by the independent safety body Underwriter Laboratories as nonflammable, compared to lithium-ion batteries, which are notoriously not. Alsym’s battery also offers superior performance at both high and low temperatures. The company’s cells will be cost-competitive with the leading lithium-ion chemistry right off the bat, Chatter told me, and the overall system will be 30% cheaper because the battery’s thermal stability and ability to perform at high temperatures eliminates the need for the costly, maintenance-heavy cooling systems. It’s a similar value proposition to that of Peak Energy, another startup seeking to deploy sodium-ion battery storage systems.
While sodium-ion cells are less energy dense than lithium-ion, eliminating the entire HVAC system means that the system itself isn’t all that much bulkier, making it possible to deploy in space-constrained environments such as commercial or residential buildings.
Alsym aims to manufacture its sodium-ion cells in the U.S., both for supply chain security and to take advantage of the country’s abundant sodium reserves. The latter, Chatter told me, means that “it will be cheaper to build it in the United States than anywhere else.”
While Alsym operates a pilot plant making sodium-ion cells, the company plans to scale its production through partnerships with third parties who either operate existing lithium-ion cell facilities or are in the process of building them, as sodium-ion cells can be produced on the same lines. “We want to partner with somebody who has that scale,” Chatter told me, explaining that a company of Alsym’s size could never compete with China by going at it alone. “But if we can partner with a much larger player who has the heft and the skill set and expertise to build large plants — or already has lithium ion plants — then we can compete head to head.”
Tata Energy, a leading power company in India worth about $14 billion, led Alsym’s Series C round. Chatter said the company also has strategic support from several mining companies, with other early use cases likely to include microgrid installations as well as primary or backup power for data centers and telecom companies.
“It’s not exactly the most glamorous space right now,” Chatter admitted, acknowledging the string of recent battery company failures. “But things happen in ebbs and flows.” He thinks the sodium-ion sector just needs one big success to prove its potential as a safer, cheaper alternative. “It really is all about cost and revenue opportunities,” he told me. If all goes according to plan for Alsym, we won’t have to wait much longer to see if he’s right.
Economist Philippe Aghion views carbon taxes as a tool to decarbonize, but not a solution in themselves.
Philippe Aghion — one of three Nobel laureates in economics announced Monday — is a theorist of innovation. Specifically, his work concerns “creative destruction,” the process by which technological innovation spreads throughout the economy as new businesses replace old ones, sparking economic growth.
If that reminds you of the energy transition, i.e. the process by which cleaner fuels and new, more efficient ways of generating energy replace fossil fuel combustion, well, you’re not alone.
“I think innovation is the best hope for climate change,” Aghion said in a 2023 interview with VoxTalks Economics. “Of course, we need to innovate in our day to day behavior, but we’ll fight climate change because we will find new sources of energy that are cleaner than coal or gas, and because we will also find ways to produce with energy-saving devices.”
Along with Brown University economist Peter Howitt, Aghion developed mathematical models to describe how creative destruction works, building on foundational work by the Austrian economist Joseph Schumpeter. Along the way, Aghion also worked with 2024 Nobel laureate Daron Acemoglu, who won his prize for describing the institutions that best foster economic growth.
Aghion and Acemoglu have tangled with fellow laureate William Nordhaus, whose models of how the harms of climate change slow down economic growth practically invented the field of climate economics. In Nordhaus’ framing, climate change is the ultimate externality — that is, an economic factor not reflected in the market. The most efficient way to solve climate change, then, is to price in the externality by putting a tax on carbon emissions. Once the price of highly emitting goods reflects the true cost of producing them, the market will naturally favor lower-emitting goods.
Aghion instead sees carbon prices as another way to spur climate-friendly innovation throughout the economy.
In a 2014 paper written with Cameron Hepburn, Alexander Teytelboym, and Dimitri Zenghelis, Aghion argued that “product and process innovation” will ultimately drive decarbonization. Previous approaches to climate economics, Aghion wrote, use inadequate models for the effects of innovation, and so “significantly bias the assessment of the cost of future low-carbon technologies” to be higher than they are in reality.
To be clear, Aghion isn’t against a carbon tax. “A carbon tax or carbon price is a tool to redirect natural charge but it’s not the only tool,” Aghion said during the 2023 interview. “You need other tools, as well,” including “subsidies to green innovation, and more generally green industrial policy.” The point is less to discourage emitters and more to encourage the producers of non-emitting technologies.
Aghion argues that climate policy needs to hit hard and hit quickly, precisely to induce the kind of competitive innovation that he thinks drives economic growth. “If you wait longer, firms will be even better at dirty technologies, and it will take longer before their skills on clean technologies catch up with their skills on dirty technologies, and so you need to act promptly,” he said in 2023.
In a 2012 paper on the auto industry written with Antoine Dechezleprêtre, David Hemous Ralf Martin, and John Van Reenen, Aghion tracks patents in the auto industry and finds that “higher fuel prices induce firms to redirect technical change towards clean innovation and away from dirty innovation.”
He also finds that the nature of the firms matters. Companies that have a background in green technology innovate more in green technology, while companies that specialize in carbon-emitting or “dirty” technologies are more likely to find better ways to emit carbon. You’d expect Porsche or Ferrari to come up with a better internal combustion engine than Tesla, for instance, but for Tesla to invest more in pushing the capabilities of electric drivetrains.
Tesla is in many ways the ideal example of this kind of policy mix working. The company has benefited both from federal and state taxes on gasoline (as well as California’s unique emissions rules), which suppress demand for fossil fuels, and from subsidies and other financial support, which helped it reach economies of scale and performance parity with internal combustion vehicles more quickly.
While theoretically every auto company had the same incentives in both California and the nation as a whole to develop electric vehicles, Tesla made up the bulk of the entire market for years as it never had to split its focus between a legacy internal combustion business and a battery electric business.
Aghion’s work supports this kind of “belt-and-suspenders” approach to climate policy, where fossil fuel emissions are made more expensive and subsidies are provided to advance green innovation.
This may sound pretty familiar. While America’s signature climate law, the Inflation Reduction Act, eschewed carbon taxes in favor of incentives and subsidies, the overall policy mix pursued by the Biden administration — including a fee on methane emissions, regulations on tailpipe and power plant emissions, and increased fuel economy standards — approximated this mix.
Aghion clearly recognized the IRA as a real life version of his ideas. When asked in 2023 about the kind of industrial policy he envisioned, he said, “The Americans are doing it now with the IRA.”
This kind of policy mix wasn’t just optimal policy economically, but also necessary politically.
Pointing to France’s experience with fuel taxes, which led to country-wide protests beginning in 2018, he cautioned that if policy makes dirty fuels more expensive without making clean technology technology cheaper, “then people riot.”
Of course, the IRA and other U.S. climate policies have not been as politically durable as their supporters hoped for. This is despite the fact that, alongside trying to boost green businesses, recent attempts at industrial policy explicitly tried to support “dirty” business, as well, whether by subsidizing older auto companies’ investments in electric vehicles or by supporting carbon capture and hydrogen investments by big oil companies.
But the power of dirty business remained immense — and opposed to climate policy.
The oil and gas industry were some of the biggest supporters of President Trump’s reelection campaign. Since he took office, one of their own — former fracking executive Chris Wright — has overseen the dismantling of much of the Energy Department’s investments in clean energy.
The basic calculus of Aghion’s approach may very well persist as rich countries struggle with growth and the harms attributed to climate change continue to add up.
“I think now we made progress on the idea that innovation is a big part of the solution and … that carbon price is not enough,” he said. “You need smart industrial policy aimed at green innovation. That’s the idea.”