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An investment boom is exploding in outer space. Investors have thrown their backing behind space-based solar power, orbital data centers, and even extraterrestrial power grids. SpaceX is pursuing an IPO — potentially the largest the world has ever seen — in part to fund its own off-Earth data center ambitions. The Space Foundation reported that the global space economy reached $613 billion in 2024, combining commercial revenue and government funding, while PricewaterhouseCoopers estimates the sector could grow to reach $2 trillion by 2040, largely driven by private sector innovation and support.
Different though they may be, these technologies all leverage the vast unknown outside our atmosphere to monitor, manage, and optimize terrestrial energy and climate systems.
This boom comes after roughly a decade of sharply falling launch costs, which has fueled a surge in satellite deployments for telecommunications and remote sensing applications. Together, these shifts have expanded the scope of what’s technically and economically possible in space — and in turn, broadened the range of systems and services needed to make this off-Earth infrastructure work.
“We’ve got over 14,000 satellites in space already, and that’s growing every day. It’s going to triple over the next five, six years,” Jeff Johnson, a general partner at the venture firm B Capital, told me. “And if you look at the other trend that’s happening, the power requirements for what’s going up in space have been growing dramatically and will continue to do so.” As Johnson explained, that’s because we’re asking satellites to do more — and to do it faster — than ever before: deliver high-speed internet globally, extend cell coverage in remote areas, and perform onboard data processing before transmitting imagery and other information down to Earth.
SpaceX, of course, has been the dominant force driving down launch costs while dramatically increasing the scale of satellite deployments with its partially reusable Falcon 9 rockets. More recently, it’s laid out an ambitious plan to put 100 gigawatts of “AI compute satellites” into orbit each year, with launches beginning as soon as 2028. As the company wrote in its S-1 filing ahead of its pending IPO, “we believe orbital AI compute is an incredibly difficult technical challenge that only we can solve at scale in the near term.” It also acknowledged, however, that the effort involves “significant technical complexity, unproven technologies, or technologies that do not exist,” and that ultimately, “such initiatives may not achieve commercial viability.”
It’s a startlingly frank assessment of an industry that holds both great potential and significant uncertainty. Much of SpaceX’s growth strategy — and likely the prospects of numerous other companies looking to launch large infrastructure into space — hinges on the success of its next-generation rocket called Starship. Designed to be fully reusable and much larger than any rocket built before, Starship will be capable of carrying roughly five to six times the volume and over eight times the massas Falcon 9. Throughout its 12 test launches so far, the rocket has seen both success and failures, accumulating mounting delays along the way.
The uncertainty around Starship’s future is one reason Johnson’s firm invested in Star Catcher, a startup that bills itself as “the first power grid in space.” He doesn’t view the startup’s value proposition as dependent on Starship’s success, betting that it can serve as critical infrastructure for satellites already in orbit today — not just for the bigger and better systems that future launch vehicles could enable.
Founded less than two years ago, Star Catcher is developing a laser-based system to beam solar energy to satellites in low Earth orbit, supplying additional power directly to their solar arrays even when they’re in Earth’s shadow. This enables satellites to perform ever more power-intensive operations. It also addresses a fundamental constraint of satellite design: A satellite is only as powerful as the size of its solar array, which must be small enough to fit inside a rocket and also degrades over time.
“The average satellite in the Earth’s orbit has like 1,500 watts of power generation, which is as much as my kids’ gaming computer uses,” Andrew Rush, Star Catcher’s CEO, told me. “But we’re saying that satellite is going to be a cell tower, it’s going to be a data center, and those are multi-kilowatt, tens of kilowatts, hundreds of kilowatts applications. There’s a big disconnect there.”
B Capital led Star Catcher’s oversubscribed $65 million Series A round, which closed earlier this month. The fresh capital will help the company demonstrate its system in orbit and move towards commercialization. Star Catcher plans to launch its own constellation of power node satellites with the sole purpose of harnessing energy from the sun — or, as Rush quipped, “the greatest fusion reactor known to humankind.” Each node will then beam that energy to other power-hungry satellites by directing concentrated, near-infrared laser light at their solar panels. This type of light can deliver far greater power density than diffuse sunlight, providing satellites with a roughly 10-fold increase in power capacity compared to what they would generate alone.
As Rush explained, this then enables both satellite and rocket companies to “shrink the size of the solar arrays, and therefore, shrink the size of the spacecraft — actually make it less complex, less massive, and therefore less costly to field.” Already, he said the startup has signed seven power purchase agreements with satellite companies such as Loft Orbital and Astro Digital, as well as agreements or letters of intent with “almost every orbital data center startup” including Starcloud, which wants to begin offering cloud computing in space by early 2027.
For its part, Star Catcher aims to scale commercially by the end of the decade. Rush argues that just as bringing data processing closer to mobile users on the ground speeds up browsing and streaming, the growth of satellite broadband will create demand for the same infrastructure in space. That means everything from caching streaming content to running AI inference and processing satellite data in orbit, thus reducing the latency involved with routing everything to space and back.
While Star Catcher is focused on providing grid infrastructure for conventional satellites and orbital data centers, another recently funded startup, Cowboy Space, wants to build those data centers itself — and the rockets that will bring them to space. The company was founded in 2024 under the name Aetherflux, with the goal of beaming solar energy from space down to Earth. But with its latest $275 million Series B fundraise earlier this month, the company unveiled both a new name and a new mission.
Modern rocket designs from SpaceX — Cowboy Space’s most formidable competitor — pair a reusable lower section with a disposable upper section that carries satellites into orbit mounted at the rocket’s tip. After that upper section releases the satellite into orbit, the now purposeless component drifts through space, eventually burning up as it reenters Earth’s atmosphere. But Cowboy Space aims to transform what would otherwise be discarded debris into an orbital, 1-megawatt data center, integrating hundreds of Nvidia chips into the rocket’s upper section.
“We started with a blank sheet of paper with a goal of packing as many GPUs as tightly and densely as possible, and getting them to space,” Joseph Yaffe, the startup’s COO, told me over email. “We believe that this is a first-of-its-kind approach — the launch vehicle and the orbital data center designed as a single integrated system from day one.”
He told me that existing launch providers couldn’t offer the launch capacity or flexibility that Cowboy Space needs, and that the economics just wouldn’t pencil unless they did it themselves. Of course that’s an extremely tall order. SpaceX currently dominates the market for private rocket launches, a sector notoriously littered with failures. Only a few other private companies have even managed to make a dent in the space, and they’re still far behind Elon Musk’s industry giant.
Yaffe naturally thinks his company is well-positioned to become the exception, and prominent backers such as Index Ventures, Breakthrough Energy Ventures, and Andreessen Horowitz seem to agree. The startup is targeting the end of 2028 for its first proprietary rocket launch. Eventually, Cowboy Space plans to deliver processing power on par with conventional data centers, with Yaffe explaining that “abundant solar power and radiative cooling in orbit are what make that cost structure achievable.”
It’s true that space-based data centers would not require the same energy- and water-intensive fans, chillers, or cooling towers used on Earth, instead dissipating heat into space via infrared radiation — essentially emitting thermal energy as invisible light. But using today’s technology, power dense satellites can’t radiate heat quickly enough to sustain AI workloads, and how Cowboy Space plans to overcome this remains an open question. Even Nvidia CEO Jensen Huang acknowledged the difficulty, remarking in a recent keynote address at the GPU Technology Conference in San Jose that “we have to figure out how to cool these systems out in space.”
But if Cowboy Space and others can overcome these technical hurdles, there are some clear advantages to putting data centers into orbit. For one, building these energy-hungry behemoths has become a fraught political issue on both sides of the aisle, with local opposition exploding this year. Then there are the familiar constraints of limited power availability and interminably long grid interconnection queues, which are preventing hyperscalers from ramping up their AI efforts as quickly — and cleanly — as they’d like.
“AI demand is growing faster than terrestrial infrastructure can scale,” Yaffe argues. He’s betting that this dynamic will hold even if policy fixes such as permitting reform eventually materialize. “Orbital data centers aren’t a replacement for terrestrial infrastructure. The long-term opportunity is about expanding total compute capacity.”
Likewise, Johnson of B Capital doesn’t see the primary value proposition of orbital data centers as alleviating power or permitting constraints. “The reason why things are moving to space isn’t because we don’t have telecommunications that work right on Earth, it’s because new use cases are getting unlocked that are better,” he told me. “The first time you’re on a plane and use Startlink, you see that. The first time you need to be somewhere that isn’t really served well by Wi-Fi, and you use it, you see that. So there’s use cases that are transformational that can get unlocked by the space economy”
Not everyone is as bullish, however. Luigi Scatteia, the lead of PwC’s global space practice, told me he expects there to be “some form of data relay in orbit.” That might look more like space-based computing networks processing data from Earth observation satellites, as we’re already seeing the beginnings of today. But full-on data centers with the capabilities of terrestrial server farms? Launched from rockets? “I’m just going to say what my professor in university always used to tell us: Anything you do on Earth is always going to be more difficult in space.”
He, too, thinks the real unlock for orbital data centers and beyond would be “if Starship really works as intended,” he told me. “If you really want to do massive things in space — if you want to have a paradigm shift, a Copernican change — you need to drastically raise the capacity and lower the cost to orbit.”
No question these are two incredibly difficult tasks, not just for SpaceX but for the broader ecosystem of emerging space startups betting that private industry can fundamentally reshape the space economy. But according to Rush of Star Catcher, investors are now increasingly willing to take that bet too, in a way they weren’t when he first entered the industry a decade ago.
“Now, there’s the full spectrum of capital available, from seed all the way through IPO and beyond,” Rush told me. And that money is flowing to “really every flavor of space company. And so just by that metric alone, this is the golden age to build in space.”
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Advanced nuclear will take a decade or more to hit commercial scale. Meanwhile, the hyperscalers need power now. Enter the uprate.
When America’s tech titans started plowing money into nuclear technology to power data centers in 2024, companies such as Google and Amazon opted to invest first in next-generation reactor startups. But electricity demand is soaring today, and those projects are still years away — at least — from generating power at reasonable commercial rates.
So the industry is hedging by betting on existing nuclear plants to pump out more electricity in the near term. Uprates — renovations that allow nuclear operators to produce more power from existing reactors — are all the rage this year.
In February, the Department of Energy issued its largest-ever loan to Southern Company to fund up to 6 gigawatts of uprates across the utility’s nuclear fleet. Last week, Amazon signed a deal with Constellation Energy, the nation’s largest operator of nuclear reactors, to uprate the Calvert Cliffs plant in Maryland to generate another 190 megawatts on top of its current 1.8-gigawatt output. Soon after, the Energy Department offered nuclear operator Vistra a $4 billion loan to uprate plants in Ohio and Pennsylvania.
Then on Tuesday, Google inked its own deal with Constellation aimed at wringing out 890 megawatts of new power from 11 reactors across PJM Interconnection, the nation’s second-biggest and arguably most overworked grid system.
“Everyone loves nuclear, but it takes a really long time to build,” Raiford Smith, Google’s head of power and energy for the cloud, told me yesterday. “The fastest way to get it is via uprates. It’s real megawatts, but the quicker, shorter-term approach.”
Building new reactors, he said, “is the intermediate term plan, and we see fusion as the longer term bet.” Given that “new data centers are coming on at a gigawatt a clip, that means even with all the uprates, there’s still more to come,” he added.
The investments into existing nuclear stations deliver a win for Constellation, whose chief executive, Joe Dominguez, has been among the more vocal C-suite skeptics of what my colleague Matthew Zeitlin described as utility executives’ “load growth mania” over the past two years. But the deals say as much about the shifting lines in the debate over how to expand the nuclear power fleet in this country — what size reactors are better, how to finance projects — as the disagreement over how much new generation is needed to supply the artificial intelligence boom.
The deal “is a win-win,” Emmet Penney, the director of energy and infrastructure at the think tank Foundation for American Innovation, told me. “Constellation and Google are revealing just how essential our nuclear fleet is to maintaining our energy dominance.”
America’s last attempt at a nuclear buildout ended in a series of financial boondoggles. The problems traced back to numerous factors: Decades without any nuclear construction atrophied the workforce. Electricity market reforms aimed at breaking up monopoly utilities left the industry with few players equipped with large enough balance sheets to take on megaprojects that would take years to build and billions of dollars of upfront capital. Increased competition from cheap natural gas.
The only two new reactors that made it over the finish line, Southern’s pair of Westinghouse AP1000s at the Alvin W. Vogtle Generating Station in eastern Georgia, came in billions of dollars over budget, in part because the developers erred in choosing a Nuclear Regulatory Commission licensing pathway that required long stops and costly delays every time the builders tweaked the design. Since those were the first AP1000s constructed in the U.S., there were plenty of last-minute design kinks to iron out.
In the meantime, the industry rallied behind the idea of small modular reactors. By making individual reactors roughly a third or less powerful than large-scale units such as the AP1000, the thinking went, developers would need to buy more, helping the technology slide down the cost curve through repeated construction and assembly-line manufacturing of components.
While Google and Amazon both backed fourth-generation startups whose designs use coolants other than water, such as liquid sodium or helium gas, the only such reactor operating in the world is in China, and America’s track record of running similar plants is poor. As such, government-owned utilities such as Canada’s Ontario Power Generation and America’s Tennessee Valley Authority have thrown their weight behind third-generation SMRs that essentially just shrink down existing water-cooled technology. The first of GE Vernova Hitachi Nuclear Energy’s BWRX-300s, a 300-megawatt design based on the boiling water reactors that make up about a third of the U.S. fleet, is now underway at OPG’s Darlington plant. In the U.S., meanwhile, the NRC just issued a construction license for the TVA’s first BRWX-300.
But the completion of the second AP1000 at Plant Vogtle demonstrated an uncomfortable reality proposed by researchers at the Massachusetts Institute of Technology: That the next, cheapest reactor to build in the U.S. would be another of Westinghouse’s flagship design. Vogtle Unit 4 came online in 2024 roughly 30% cheaper and faster than its slightly older twin, Vogtle Unit 3.
If that reduction seemed to justify the approach SMR companies were pursuing, a report by an economist and former antinuclear researcher raises new questions. The study by Charles Komanoff, which I covered here last month, suggests that the number of reactors required to achieve major cost reduction through “economies of duplication” pales in comparison to the price drop achieved through “economies of scale.” In other words, the nuclear industry’s time-tested approach to making reactors more economical — making them bigger — is still the best bet.
The Trump administration certainly agrees. The Energy Department laid plans for at least 10 new AP1000s last year, and put up another nearly $20 billion loan package for utilities that form joint ventures with Westinghouse to build one of the 1,100-megawatt reactors. South Korea is currently working out the fine print on a deal to help finance and build as many as six AP1000s and two APR1400s, the Korean rival to the Westinghouse reactor.
Whether any American utilities step up to help build any of those AP1000s remains an open question.
“There’s no way any utilities could consider building a large AP1000 because doing so could bankrupt the whole operation, and they don’t have enough confidence,” Chris Gadomski, the lead nuclear analyst at the consultancy BloombergNEF, told me.
The workforce that constructed the two AP1000s at Vogtle, he said, are now out building data centers. Unlike the Chinese, whose state-owned nuclear companies reverse engineered the AP1000 and made it relatively cheap to build by constructing as many as half a dozen at a time at one location, “we don’t have the wherewithal or sites in this country to build six reactors at once,” Gadomski said. “You’re lucky to build two at one site in this country.”
So fusion and next-generation fission remain years away. Current-generation SMRs come with big questions. And the leading large-scale design, the AP1000, is proving a hard sell to utilities. That leaves two options: Restarting decommissioned plants and uprating current reactors. The Energy Department has pumped billions in loans into projects to restart at least three permanently closed reactors: Holtec’s Palisades plant in Michigan, NextEra’s Duane Arnold facility in Iowa, and Constellation’s Crane Clean Energy Center, née Three Mile Island, in Pennsylvania. The consensus among industry experts is that those are the only three that remain intact enough to start back up; every other shuttered plant is at too advanced a stage of demolition.
That leaves uprates.
There are limits to how much power can be drawn from existing plants, said Jeff Jenkins, the founder and managing partner of Bernhard Capital Partners, an investment firm whose portfolio includes Allied Power, a contractor that has worked with Constellation on past uprates. “There’s still a few gigawatts out there,” he said. “And a gigawatt is a lot.”
But ultimately, the U.S. nuclear buildout needs options.
“It’s very much a hedge,” Gadomski said. “They’re spreading their bets. That’s a strength of Google’s strategy. They’re willing to place bets on advanced reactors, fusion, and still try to double down on the capacity of existing plants.”
On methane rules, British wind, and the Israeli electricity market
Current conditions: Singapore’s air is the worst in the world as wildfire smoke from Indonesia chokes the city state and neighboring Malaysia • Following a summer-like heat wave, temperatures in the American West are set to drop by as much as 50 degrees Fahrenheit as a cold snap moves in • In the Gulf of Mexico, Tropical Storm Isaias officially strengthened into the first Atlantic hurricane of the season this morning.
With its offshore oil fields booming in Guyana and its opportunities opening in Venezuela, Exxon Mobil is eyeing the next location for the Americas’ oil and gas: Trinidad and Tobago. In an interview with the Financial Times this week, the company’s exploration chief said the island nation’s existing oil and gas industry could expand to tap the same basin east of Venezuela that has transformed Guyana from one of the hemisphere’s poorest nations to one of its richest in terms of per capita gross domestic product. “A lot of people ask, ‘well, where’s the next Guyana?’” John Ardill, Exxon Mobil’s vice-president and head of global exploration, told the newspaper. “In Trinidad, we moved in as a play extension to Guyana.” The agreement between Exxon Mobil and the Trinidadian government took “about half as long as it usually takes on a good day,” delivering a pact in “record time.”
America’s oil majors are also looking outside the hemisphere. As you may recall from August, I told you that Exxon Mobil was also considering a big investment in Africa, with Mozambique drawing particular attention. Brazil’s state-owned Petrobras, meanwhile, is expanding its own grasp on the Americas’ oil boom. On Wednesday, Upstream reported, the company bid $590 million for control of an ultra-deepwater concession.
The European Union is pausing implementation of its new rules requiring oil and gas exporters to more scrupulously track data on methane emissions. The U.S., on the other hand, is planning a straight-up rollback. At an oil industry conference in Santa Fe on Wednesday, Environmental Protection Agency Administrator Lee Zeldin teased out plans to gut core parts of the methane regulations finalized in 2024. “This proposal takes on many of the problems American producers and operators have raised with us,” Zeldin said, according to Argus Media. “That includes the burden on marginal wells and oil and gas operators in general, the super emitter program, associated gas and control device requirements.”
Record wind power generation may have slashed how much natural gas Britain needed to burn last month for electricity, but it “wasn’t enough to shield the country from surging prices triggered by the war in Iran,” Bloomberg reported. Wind turbines pumped out 6.6 terawatt-hours of electricity in September, a record for the month and 4% more than a year earlier. As a result, gas-fired generation plunged to its lowest level on record for that month. But day-ahead power rates still doubled from a year earlier.
The world’s capacity of floating offshore wind, the subset of the sector that could vastly expand the areas of shoreline dotted with turbines, has reached 382 megawatts, a 38% surge over the past 12 months, according to a Renewables Now writeup of the latest report from the trade group RenewableUK. Meanwhile, Poland has now constructed all 76 of the standard turbines built into the seabed of the Baltic Sea for its first offshore wind farm. One-third of the turbines are now generating power, according to offshoreWIND.biz.
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South Korea plans to speed up its shift away from fossil fuels with a new goal of 100 gigawatts of low-carbon energy additions by 2030 and roughly $747 billion in government-led investment over the next decade. The plan, part of the Korean Green Transformation program, “seeks to make Korea one of the world’s top three green manufacturing powers by developing industries such as hydrogen-reduction steelmaking, next-generation solar cells, and all-solid-state batteries,” according to The Korea Times, an English-language daily. New nuclear reactors are also part of the strategy.
The move comes as Seoul advances construction of as many as eight nuclear reactors in the U.S., including six of America’s Westinghouse AP1000 and two of its own APR1400s, as I told you last week.
The utility megamerger of the century so far is “not in the best interest of Virginians.” That’s the judgment the state’s lieutenant governor, Ghazala Hasmi, rendered this week following a five-city public listening tour. The statement came ahead of the State Corporation Commission’s first local hearing on the deal, and marks what Utility Dive called “the most formal expression of opposition from Virginia’s executive branch so far.” Governor Abigail Spanberger, a fellow Democrat, has not yet taken a definitive position on the merger.
But the deal follows some clear market logic. Among the benefits: It would create, as my colleague Matthew Zeitlin wrote in May, “a storage juggernaut.”

Israel’s booming tech sector and soaring stock market are just two ways its economy has dramatically changed from the socialism that defined the early decades after the country’s founding in 1948. Now that shift also includes the electricity market. Since market reforms allowed private actors into the grid at the start of last year, more than 2 million citizens, representing more than 500,244 private and business customers, have switched from the Israel Electric Corporation to private providers, according to The Jerusalem Post. Ratepayers buying electricity from private suppliers enjoy discounted rates ranging from 7% to 20%, “thanks to the lower generation costs in the private market.” Another 23,286 households and businesses submitted requests to switch suppliers just last month. OPC Energy, an independent power provider based in Tel Aviv, raised $200 million in bond issuances in August.
The announcement follows a Series A round that included investment from the Department of Defense.
The U.S. wants to make more of its own rare-earth magnets, which are critical to everything from guided missiles to aerospace systems and electric vehicle motors. But doing so will require a domestic source of high-purity iron, the main material in these magnets and one the U.S. imports almost entirely from China. Hertha Metals is betting it can fill that gap while helping decarbonize the ironmaking process, too. After raising a more than $133 million Series A, which the company announced last week, the Texas-based startup is promising to supply domestic magnet and steel manufacturers with 10,000 metric tons per year of lower-carbon, high-purity iron. That will come from its first commercial facility near Houston, where the company broke ground on Thursday.
Steel customers, including automakers and other equipment manufacturers, have already expressed interest in Hertha’s tech. But the startup’s most important customer might be the federal government. Defense manufacturers depend on rare-earth magnets — which require 99.95% high-purity iron — for things like aerospace platforms and radar systems. That explains why the Department of Defense invested $65 million in Hertha’s Series A through its Industrial Base Analysis and Sustainment program. The investment comes in partnership with the Economic Defense Unit, a new Pentagon division established under Trump that makes grants, loans, equity investments and purchase commitments into defense and dual-use sectors like critical minerals.
Hertha’s CEO and founder Laureen Meroueh called the new facility — sited next to its operational demonstration plant — the nation’s “first domestic iron and steel innovation complex” when I spoke with her in April to learn more about the company’s technology. She expects the plant to be operational by the end of next year.
That’s thanks to a new proprietary process that Meroueh, a mechanical engineer and materials scientist by training, pioneered. “We find ourselves in the year of 2026 making steel out of the same furnace that was developed in 1850. That’s insanity,” Meroueh told me. Today, most iron is produced by stripping oxygen from ore in a furnace that operates at over 3,000 degrees Fahrenheit. Called a blast furnace, this towering steel-and-brick shaft is fueled by coke made from metallurgical coal. The resulting molten iron then enters a basic oxygen furnace, where it’s refined into steel. Producing the higher-purity iron needed for rare earth magnets requires additional refining steps to remove impurities.
While lower-emissions alternatives do exist, they come with their own limitations. Direct iron reduction, for example, uses hot gas to strip oxygen from ore, then melts the resulting solid iron in an electric arc furnace. But the process typically requires higher-grade ores to begin with, and thus remains a small share of global production. Electric arc furnaces can also recycle steel scrap — indeed most domestic steel is produced this way — but supply is finite. Meanwhile, ore quality is decreasing over time, limiting the grades of steel it can ultimately produce.
Enter Hertha, which says it can turn low-grade iron ores into high-purity iron in a single furnace. Meroueh explained that Hertha uses either natural gas or hydrogen to strip oxygen from molten ore in an electric arc furnace, with no separate reduction step beforehand. Because the furnace melts down the ore and its impurities from the outset, it can accept low-grade ore in many forms, including fines, the powdery particles left over from mining and processing. When everything is molten, the lighter impurities separate from the denser iron and form a layer of slag that operators can then drain from the furnace. The resulting iron needs only minimal additional refining to go into rare earth magnets.
“This is a continuous reactor, so you continuously feed it and semi-continuously tap out your slag and product,” Meroueh explained. Melting iron made from ore produces far more slag than standard electric arc furnaces are designed to handle, and would thus require frequent interruptions in operations. But Hertha’s proprietary process doesn’t need to do that. “This continuity in operations is what makes it economically viable for us to generate large amounts of slag while maintaining production and throughput.”
The startup also says it can make steel using the same process by adding a controlled amount of carbon to its single furnace. While Hertha hasn’t provided an estimate of avoided emissions for this plant specifically, it says a third-party modeler has projected that its subsequent 500,000-metric-ton facility will emit up to 50% less than conventional blast furnace steel production when running on natural gas, and 98% less when running on green hydrogen.
Hertha also expects its process will cut costs by 25% compared with blast furnaces, and says its system can make full-cycle steel plants as small as 500,000 metric tons per year economically viable. Most steel mills that use a blast furnace to convert raw materials into finished steel produce 3 million metric tons or more annually, making this future plant the size of a so-called “mini mill,” which recycles scrap metal in an electric arc furnace rather than starting with the iron ore.
The 10,000-metric-ton facility the company is currently building will start by running on natural gas, which is still far cheaper than green hydrogen. But Meroueh told me that once green hydrogen falls below $5 a kilogram — and ideally below $3 — she expects it will make economic sense for Hertha to start blending hydrogen with natural gas, potentially in the early 2030s.
Outside the U.S., Hertha could reach ultra-low carbon production even sooner. “So with the really attractive renewable power prices in the Middle East, it makes it a lot more digestible to produce green hydrogen,” Meroueh told me in April. “And the best use case of that green hydrogen is to make steel. Moving hydrogen around in pipelines, not attractive. Converting it to ammonia and then back to hydrogen is not very attractive. Just make the steel right there.”