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The Inflation Reduction Act is already transforming America. But is it enough?

In the late spring, a scene happened that might have once — even a few years ago — seemed unimaginable.
Senator Joe Manchin and Energy Secretary Jennifer Granholm visited the town of Weirton, West Virginia, to celebrate the groundbreaking of a new factory for the company Form Energy. The factory will produce a new type of iron battery that could eventually store huge amounts of electricity on the grid, allowing solar and wind energy to be saved up and dispatched when needed.
Manchin was clear about why everyone was gathered in Weirton. “Today’s groundbreaking is a direct result of the Inflation Reduction Act, and this type of investment, in a community that has felt the impact of the downturn in American manufacturing, is an example of the IRA bill working as we intended,” he said.
It’s been nearly a year since the Inflation Reduction Act, President Joe Biden’s flagship climate law, passed. The law is successful. It is transforming the American energy system. And the Biden administration is implementing it as fast as it can: Since the law passed, the Treasury Department has published nearly three dozen pieces of complicated rules explaining how the IRA’s billions in subsidies can actually be used.
But is the IRA successful enough? The pace and scale of the climate challenge remains daunting. A recent report from the Rhodium Group, an energy-research firm, found that the United States would only meet its Paris Agreement goal of cutting carbon emissions in half by 2030 with more aggressive federal and state policy.
Here are some broad observations about how the IRA — and the broader project of American decarbonization — is going:
Politically, environmentally, no matter how you look at it: The power sector is the thumping heart of the I.R.A. Because engineers know how to generate electricity without producing carbon pollution — using wind turbines, solar panels, nuclear plants, and more — the sector is central to the law’s implicit plan to decarbonize the American economy, which requires, first, building as much zero-carbon electricity infrastructure as possible, while, second, shifting as much of the rest of the economy to using electricity — as opposed to oil, gas, or coal — as possible.
The electricity industry is also the site of perhaps the law’s most powerful climate policy — and its only policy tied to a national emissions-cutting goal. The law will indefinitely subsidize new zero-carbon electricity until greenhouse-gas pollution from the American power sector falls 75% below its 2022 levels. That means these tax credits could remain in effect until the 2060s, according to an analysis from the research firm Wood MacKenzie.
This was a first for American environmental law, and it remains poorly understood by the public. Even some experts claim that the electricity credits will phase out in 2032 with the I.R.A.’s other subsidies — when, in fact, 2032 is the earliest possible year that they could end.
Which is all to say that it’s early days for understanding the I.R.A.’s effect on the power sector. The data is provisional.
Yet the data is … good. Better than I expected when I started writing this article. The overwhelming majority of new electricity generation built nationwide this year — some 83% — will be wind, solar, or battery storage, according to federal data. Although that mostly reflects projects planned before the IRA was passed, it’s still a giant leap over previous years, and it suggests that the law might be giving clean electricity a boost at the margin:
The solar industry, in particular, is surging. The industry just had its best first quarter ever, with rooftop installations booming and some big utility-scale solar farms finally coming online.
But solar can’t power the entire grid, and other renewables are having more trouble. I’m particularly worried about offshore wind. To build a new offshore-wind project, companies bid for tracts of the ocean floor in a government-run auction. Yet many of those bids failed to account for 2021 and 2022’s rapid inflation, and some developers are now on the hook for projects that don’t pencil out. Most outside analysts now believe that the Biden administration will fall short of its goal to build 30 gigawatts of offshore wind by 2030.
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The boom in electric vehicle and battery manufacturing is clearly the I.R.A.’s brightest spot. (The two industries are one and the same: If you have a giant battery, you’re probably going to put it in an EV; and about a third of every EV’s value comes from the battery.)
Since the IRA passed, 52 new mining or manufacturing projects have been announced, representing $56 billion in new investment, according to a tracker run by Jay Turner, a Wellesley College professor. If you zoom out to all of Biden’s term, then more than $100 billion in EV investment has been announced, which will create more than 75,000 jobs, according to the Department of Energy.
It remains to be seen, however, whether this investment will produce the kind of durable, unionized voter base that the Biden administration hopes to form. So far, much of this investment has flowed to the Sunbelt — and in particular, to a burgeoning zone of investment from North Carolina to Alabama nicknamed the “Battery Belt.” These states are right-to-work states with a low cost-of-living, like much of the states that have absorbed manufacturing investment since the 1980s.
This might make Republicans think twice about undermining the IRA, but it might also be a missed opportunity.
In order to cheaply decarbonize its grid, America needs better power lines. Building long-range, interregional electricity transmission will allow the country to funnel clean energy to where it’s needed most. According to a team led by Jesse Jenkins, a Princeton engineering professor, 80% of the IRA’s carbon-reduction benefits could be lost if the United States doesn’t quicken the pace of new transmission construction. (Other models are less worried.)
Yet the effort to build more power lines — and the broader campaign to reform some rules governing permitting and land use, especially the National Environmental Policy Act — is probably over, at least in this Congress. Republican lawmakers figured out that Democrats are desperate for transmission reform, and they were prepared to make the party pay a high price for it — too high a price for much of the caucus. The bipartisan deal to raise the debt-ceiling also contained many of the moderate permitting reforms that Democrats might have accepted as part of a broader bargain over transmission.
Democrats are now stuck hoping that the Federal Energy Regulatory Commission, or FERC, will make smaller, more technocratic improvements to the transmission process when they take a majority of the commission’s seats early next year.
The biggest programs in the IRA target mature technologies, like solar, wind, and EVs. But the law is full of unheralded programs meant to encourage the development of early-stage climate technologies, such as sustainable aviation fuel. By encouraging technological progress, these programs could abate hundreds of millions of tons of carbon a year in the decades after 2030. They may prove especially important at reducing emissions outside the United States, according to a new analysis from Rhodium Group.
Which is to say that they could be — from a world-historic perspective — some of the law’s most important policies. But for now, few of these programs have been implemented, and we don’t really know how they’re going to go.
Some of them may also be devilishly hard to set up. My colleague Emily Pontecorvo has reported on the difficulty of setting up the tax credits for green hydrogen, which are some of the law’s most generous. If successful, the credits could give the U.S. a major new industry to tackle the decarbonization challenge; if unsuccessful, they could screw up the American electricity system.
Right now, most of the law’s consumer-facing tax credits are continuations of old policies — such as the longstanding subsidy to install rooftop solar — rather than something new. Perhaps the most expansive subsidy that consumers have seen so far is the new $7,500 tax credit for leasing an electric vehicle.
But many more programs will eventually come, including the IRA’s rebates for heat pumps, induction stoves, and electric water heaters. Those programs, some of which must be administered by state offices, have largely yet to be set up. (Even so — and in keeping with other encouraging trends — heat pump sales outpaced furnace sales in the U.S. for the first time last year.)
The Department of Energy is an agency transformed. The IRA held out the opportunity that the agency could metamorphose from an R&D-focused nuclear-weapons storehouse into the federal government’s dynamo of decarbonization. The Biden administration — and Energy Secretary Jennifer Granholm — has seized that opportunity.
As I wrote earlier this year, the agency has stepped into the role of being America’s bureau of industrial policy, replete with its own in-house bank. It has published some of the most detailed and sophisticated federal industrial plans that I’ve ever seen.
And it is getting admirably specific about each of the technologies in its portfolio. In a recent report on the nascent hydrogen industry, for instance, the department said that companies might not build out enough infrastructure because they can’t count on future demand for clean hydrogen. (It’s impossible for firms to invest in making hydrogen if they can’t be sure anyone is going to buy it.) Then, earlier this week, the agency announced a new $1 billion program to buy hydrogen itself, thus providing that demand-side certainty that producers need.
Let’s return to renewables. The United States is striving — but will likely fail — to build 30 gigawatts of offshore wind by 2030. It is building a couple dozen gigawatts of new solar capacity every year. That may seem like a lot: One gigawatt of electricity is enough to power about 825,000 homes.
But annual power demand in the United States is closer to 4,000 gigawatts — and it’s on track to grow as we electrify more and more of the economy. While decarbonizing the grid isn’t as simple as switching one energy source for another, still, it would take more than a century to build 4,000 gigawatts of renewables electricity at our current rate.
It’s a similar story in electric cars. The growth is good: EV sales rose 50% year over year in the first half of 2023. But the challenge is daunting: Electric vehicles made up only 7% of all new car sales in the U.S. during the same period, and decarbonizing the car fleet will eventually require making virtually all new car sales EVs, and then — over the next decade — replacing the 275 million private vehicles on the road.
And that’s the story of the IRA — from renewables to EVs, geothermal to nuclear energy. The trends have never been better. The government has never tried to change the energy system so quickly or so thoroughly. That, by itself, is progress: For decades, the great obstacle of climate change was that the government wasn’t trying to solve it at all.
But decarbonization will require replacing hundreds of millions of machines that exist in the world — and doing it fast enough that we avoid dealing catastrophic damage to the climate system. The IRA is about to take on that challenge head-on. Now we find out if it’s up to the task.
The real work, in other words, is just beginning.
Read more from Robinson Meyer:
The East Coast’s Smoke Could Last Until October
The Weird Reasons Behind the Atlantic Ocean’s Crazy Heat
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New research from Climate Central estimates the rise in heat-related emergency room visits due to climate change.
2027 is very likely to be the hottest year ever recorded. Though heat was the climate story of the summer — the ocean heat that dictates the severity of El Niño; the back-to-back heat domes in Europe that killed an estimated 35,000 people; the U.S. experiencing its hottest month in 130 years, breaking the Dust Bowl record — what lies ahead will be, in all likelihood, nothing our species has ever experienced before.
We need to get better at understanding and adapting to extreme heat because lives are on the line. But there is also a lot of bad stuff that happens to people before they actually die from the heat. While excess mortality rates are an important (albeit tricky) way of measuring how bad a heat wave is, climate change-related heat is also fueling an increase in emergency room visits, new peer-reviewed research by Climate Central found.
In a study released Wednesday looking at warm months in the years 2018 to 2025, Climate Central found that the observed rate of heat-related ER visits averaged 130 per 100,000 total visits, compared to a modeled rate of just 95 visits under counterfactual temperature conditions — that is, what temperatures would be without the influence of human-caused climate change. That means human-caused planetary warming directly accounts for about 35 visits per 100,000, or 27% of heat-related emergencies.
While the Sun Belt had the highest overall rates of heat-related ER visits, as expected, the largest relative climate fingerprint appeared in the Northeast (41%) and New England (37%), likely because these regions are far less acclimated to (or built for) extreme heat. Likewise, while July had the highest overall number of ER visits, being the hottest month of the year in the U.S., September showed the highest percentage attributable to climate change (33%) as heat impacts have begun to extend later into the fall.
Measuring emergency room visits might seem superfluous compared to measuring deaths, the latter being the more traditional headline number after an extreme weather-related tragedy. But Kristina Dahl, the vice president for science at Climate Central, told me that her group’s research is part of an emerging branch of attribution science called impact attribution.
“We’re trying to go beyond attributing the physical climate variables like high temperature and see how climate influence percolates into the whole chain of events,” Dahl said. “There’s a lot of literature that shows that heat-related illness increases when temperature increases, and there are a lot of studies that translate high temperatures into deaths and heat-related mortality. But we haven’t seen anything that looks at the lower-level health impacts related to heat exposure.”
Lower-level health impacts are crucial to understand, though. For one thing, more ER visits strain health systems in potentially lethal ways as wait times, premature discharges, and occupancy climb, resources dwindle, and care is rationed, earlier research has found.
Take the 2021 Pacific Northwest heat dome, the most extreme three days in the entire Climate Central record, with an observed rate of 6,763 heat-related ER visits per 100,000. About 1,834 of those visits, or 27%, are attributable to climate change, the researchers found. The Pacific Northwest “probably still would have seen a big spike in ER visits for heat-related illness during that event, even without climate change, because it was so extreme,” Dahl told me. But even a handful more heat patients than usual can gum up an ER, since treating conditions such as heat exhaustion and heat stroke requires lowering a person’s core body temperature slowly back to its normal range. Separate research has found that hospitals are more likely to discharge patients early to free up beds during heat waves, also raising mortality rates.
A visit to the ER isn’t just scary and disruptive; it can also be extremely expensive for whoever’s in the bed. “Our healthcare system is a really challenging system to navigate. It’s strained in a lot of ways, and people’s wallets are also strained because of it,” Dahl pointed out. Understanding how ER visits strain the health care system at large can also help administrators better stage ambulances and personnel ahead of extreme heat events — and invest in workforce expansion and infrastructure upgrades to prepare for the eventuality. Ideally, interventions can prevent people from end up in the hospital at all. Workplace heat protection policies, community cooling centers, and nature- and infrastructure-based cooling solutions are all vital.
There is a critical caveat to the Climate Central analysis, however: The data it uses to calculate heat-related ER visits comes from a Centers for Disease Control and Prevention initiative called the National Syndromic Surveillance Program. More than 85% of U.S. emergency departments report to the NSSP within 24 hours of a patient coming through the doors, conveying the chief complaint that a patient arrives with. “That could be someone saying, ‘I think I have heat exhaustion,’ or ‘I’m super dehydrated,’” Dahl said.
But because of that human element — and because a person having a heart attack isn’t likely to come in saying, “Hey guys, I think I’m having a cardiac event exacerbated by extreme heat” — Climate Central’s analysis faces the same limitations as other excess mortality reports that rely on reporting systems not designed to measure heat impacts. (This is also why NPR recently calculated that the number of people who die from extreme heat in the U.S. each year is likely five times greater than the official CDC numbers.)
When I pressed Dahl on the question, she agreed that Climate Central’s research offers “a conservative look” that could lead to an undercount. “We also know that in parts of the country where physicians don’t typically see heat illness, they tend to be a little less likely to code a visit as heat-related,” she added.
This isn’t a knock on Climate Central’s analysis — rather, it’s frightening to think that the real rates of heat-related hospital visits, much less all visits directly attributable to climate change, are probably much higher. Researchers, of course, need to be careful not to sensationalize, especially since sloppy data and poor science communication can lead to misconceptions and underestimations about the dangers of heat among the population. But it pays to understand what is happening; a surge in ER visits is another piece of the public health puzzle. Hopefully someone is paying attention, because the planet’s hottest summer — if prevailing trends bear out — is now only 41 weeks away.
Here are the major dates on the climate and energy calendar.
This is an edition of Heatmap Daily, an evening review of the day’s news written by our executive editor. Sign up for it here.
The Labor Day weekend is over, so today marks the unofficial start of fall in the United States — and my return to writing Heatmap Daily. Many thanks to Emily Pontecorvo for holding down the fort while I was on vacation.
As the seasons change (at least in a non-meteorological, non-astronomical capacity), I’ve been thinking about what the rest of the year might look like. Only 114 days separate us from the end of 2026, and between now and then, we're going to get answers about some of the country’s — and world’s — biggest ongoing climate and energy questions. By December 31, for instance, we’ll almost certainly know whether Congress has reached a deal on bipartisan permitting reform, and we’ll be watching a likely record-breaking El Niño kick into high gear around the world. The U.S. political system will also be gearing up for the next presidential election.
I’ll have more on some of the biggest questions I’m thinking about later this week, but first I wanted to lay out the map. Here’s a guide to the biggest remaining dates on the climate and energy calendar in 2026.
September 22 to September 28
Every year, world leaders descend on New York City for the UN General Assembly’s week of high-level meetings … at the same time that climate and energy wonks try to scrounge hotel rooms for New York Climate Week, the closest thing that the climate and decarbonization industrial-advocacy complex has to an annual confab.
This year, another event will be added to the mix. President Xi Jinping of China is supposedly skipping the UN meeting this year, but he will be staying just a few hundred miles away on the same exact days for what seems to be a Trump-hosted state visit in Washington, D.C. This will be the Chinese leader’s first state visit to America in more than a decade, and it will come, presumably, as U.S. relations with its neighbors and allies reach a recent nadir. Given the host country here, I wouldn’t expect to hear too much about climate change, but AI, trade, and Taiwan will all likely be on the schedule.
You can expect to hear a lot about climate change (and national energy policy, and the data center boom, and much more besides) at Heatmap House, our all-day gathering at New York Climate Week on September 23. Subscribers can register now, and speakers include former Vice President Al Gore, Secretary of Energy Chris Wright, and more.
October 4, 2026
Voters in Brazil will elect the country’s president, vice president, and members of its National Congress for the first time since former President Jair Bolsonaro attempted a military coup in 2022. Bolsonaro is under house arrest for his role in the attempted autogolpe, so he can’t run; instead, his son Flávio Bolsonaro is standing. The incumbent President Lula da Silva leads in the polls. Under Lula, Brazil has pledged to cut its greenhouse gas emissions by roughly two-thirds below their all-time high by 2035.
November 3, 2026
On the first Tuesday in November, Americans will vote for the full membership of the House of Representatives as well as one-third of the Senate. Democrats are expected to retake the House — it would, at this point, be a shock if they didn’t — but the president’s polling has become so dire that they’re hoping to beat the odds and take the upper chamber, too. If Democrats succeed in winning Congress outright, expect the second half of President Trump’s term to look quite different, with liberal lawmakers running aggressive oversight campaigns in the run-up to the 2028 presidential election. Interior Secretary Doug Burgum’s plan to overhaul the National Parks Service, for instance, seems like just the kind of effort that could falter in a more scrutinized environment; the Trump administration’s extrajudicial war on wind will also likely face more oversight than it has so far. Trump would also presumably have a much harder time making judicial and Executive Branch appointments.
Even though Election Day isn’t until November, early voting starts in less than a month in some states. Expect to hear a lot more about data centers and electricity bills between now and then. Some state-level races — particularly those in Michigan, Georgia, and Pennsylvania — could also shape the field for the upcoming 2028 presidential election. (Whether Senator Jon Ossoff of Georgia runs for president, for instance, will depend heavily on who wins that state’s governor’s race — and could appoint his successor.)
November 9 to November 20, 2026
The UN’s annual climate conference will be in Antalya, Turkey, this year and begin just a few days after the U.S. midterms. This is going to be a weird summit: Turkey is hosting the physical meeting, but Australia is nominally the “political” host. The conference is supposed to focus on clean energy, zeroing waste, and methane reduction. This will be the 31st meeting of the Conference of the Parties to the UN Framework Convention on Climate Change, and it may offer a look at what a post-Trump, post-1.5 degree Celsius UN meeting could look like.
The industry has gotten excited before, to no avail. Will it stick this time?
Over a decade ago, when the global price of silicon-based photovoltaic modules was roughly five times what it is today, the solar industry and media were already hyping up the next big thing: perovskites, a class of materials defined by their specific cube-like crystal structure. The technology promised to boost photovoltaic efficiency while driving down costs, and the industry was atwitter.
“All the cool solar-cell scientists are working on perovskites photovoltaics,” IEEE Spectrum proclaimed in a 2014 article. In the same piece, Oxford Photovoltaics predicted that it would have commercially available cells within four years. The Wall Street Journal profiled the tech that same year, and in 2015, The Guardian declared that perovskites could be “game changing.” The excitement centered around the potential for higher output at lower costs: Perovskite cells were seeing rapid efficiency gains, could be made from cheap materials, and were remarkably thin and lightweight. When the question of durability came up, it was often as an afterthought. But that has turned out to be the technology’s biggest obstacle.
“What the industry came to understand very quickly is that, yes, you could see higher efficiency, but that material is going to degrade pretty quickly,” Laureen Sanderson, chief communication officer at the perovskite startup Cubic PV, told me. “A lot of the efficiency records that you were seeing were records that were achieved on very small scale devices in a laboratory environment, potentially measured in the dark.” Not ideal for a technology designed to soak up the sun on a large scale.
It’s true that perovskite cells tend to break down rapidly on contact with moisture, heat, and light, a problem scientists have been slowly chipping away at in the lab. That fragility largely arises because perovskites are made of electrically charged ions held together mostly by the attraction between positive and negative charges, much like magnets snapping together. That’s an intrinsically looser structure than the covalent bonds in silicon, which fuse the atoms together via shared electrons. As a result, the ions in perovskites migrate when exposed to the elements, accumulating in places where they react with surrounding materials to form unwanted byproducts that gradually break down the cell’s structure.
But while durability has been its fatal flaw, efficiency is perovskite’s superpower. Silicon’s efficiency tops out at 29.4%, a fundamental physics limitation that no amount of engineering can overcome. But because perovskites can be tuned to absorb different wavelengths of light beyond what silicon can capture, stacking a thin perovskite cell atop a conventional silicon cell lets the combined device make use of more sunlight than either material could alone. In July, one of these silicon-perovskite tandem cells — the industry’s dominant architecture — set a new 35.5% efficiency record.
So while this new tech still doesn’t match the stability of conventional panels, it’s getting much better. Tandem cells hold up increasingly well when exposed to heat, light, and moisture in the lab, and early outdoor trials are starting to produce promising real-world performance data. With headlines about perovskites starting to roll in once more, scientists say there’s good reason to believe that, this time around, the hype might actually be justified.
“Over the better part of a decade, there’s been lots of, for want of a better word, device engineering to engineer the material to just be much more stable,” Sam Stranks, an energy materials professor at the University of Cambridge and co-founder of perovskite startup Swift Solar, told me. That includes swapping out an unstable chemical building block in perovskites called methylammonium with a more stable one called formamidinium, improving the connection point that binds the perovskite layer to the electrode layer, and improving the packaging of perovskite cells to seal them off from air and moisture.
“There’s still work to be done to really get it to the point where you could put it up on a rooftop for 25 years and you know it will last. But the trajectory is very promising,” Stranks said.
Scientists have managed to extend perovskite durability from mere hours to the point where cells and modules are now passing industry-standard tests that suggest they could survive outdoors for five to 10 years. That’s still a ways away from the standard 25-year warranties for silicon solar panels, which typically guarantee that a module will retain 85% to 90% of its original output by year 25. And because these latest perovskites simply haven’t been around that long, scientists have yet to test these more ambitious durability claims in the real world.
Industry experts say there’s no reason continued incremental improvements can’t get perovskites to that 25-year standard relatively soon, however. “If you look at silicon, it’s been 70 years of trial and error,” Scott Wharton, CEO of perovskite startup Tandem PV, told me. “Seventy years of constant tweaking and improvement, whereas perovskites have only had about 12.”
Wharton said that Tandem’s testing indicates its panels will degrade at a rate of less than 1% per year. Furthermore, he predicts perovskites will become the dominant solar technology by 2033, a more ambitious timeline than others in the industry typically project. But as he sees it, seven years is roughly enough time to build and deploy two generations of perovskite factories — the kind of iterative ramp-up he says new technologies typically need to achieve market dominance.
The economics just make sense, he told me. Because perovskites are more efficient, they will produce more power per unit — which means less land, hardware, wiring, and labor needed to achieve the same total energy output, driving down costs at every step of the process. Why wouldn’t everyone jump onboard immediately? “All of our customers have said that once we’ve proven it out, they’re going to move,” Wharton told me. “They’re going to move 100% to tandems because of the power of the efficiency gains.”
Others are somewhat more measured regarding how long this may take. Stranks predicted it would be about five years before perovskites with multi-decade warranties even begin hitting the market, while Sanderson estimated they’ll gain real commercial traction by 2029, with perovskites making up a “significant portion of the market” throughout the 2030s.
While the date of that tipping point remains up for debate, the industry appears to have largely settled the question of materials. At least for now, the preferred configuration is to pair a lead-based perovskite cell with silicon rather than build an all-perovskite cell, which would likely face even greater durability challenges. That’s because such a cell would also need a tin-based perovskite layer to capture lower-energy light like silicon does, but tin degrades even faster than lead. In other words, it’s easier to keep silicon — a proven, durable material — in the mix by building so-called “tandem cells” for the foreseeable future.
But there’s still plenty that remains unknown. Every startup’s exact chemistry is proprietary, and there’s no clearly dominant formula yet. There’s also no industry consensus on the architecture best poised to address perovskite’s stability challenge, either, with leading players typically taking one of two different approaches.
Stranks’ Swift Solar team is pursuing what’s known as a “two-terminal” tandem architecture, in which a manufacturer builds the perovskite layer directly on top of the silicon layer, with the two cells functioning as a single unit. That’s opposed to a “four-terminal” design, where companies build two independent perovskite and silicon cells and then mechanically stack them on top of each other rather than fusing them together.
Two-terminal is the more widely studied approach, pursued by other industry leaders such as Oxford PV — the same company that once predicted commercialization by 2018 — along with Chinese solar giants LONGi and JinkoSolar. Proponents argue that using fewer material layers means less light lost, which translates into greater efficiency and lower costs. In a blog post last year, Swift Solar’s team also argued that the four-terminal designs rely on laser cutting, which it says can create more entry points for degradation.
Two-terminal isn’t just the leading theoretical contender, it’s the first architecture to officially make it to market. Oxford PV’s finally executed its long-delayed commercial launch in 2024, shipping its modules to an undisclosed U.S. customer for use in a utility-scale solar project. It was the world’s first commercial sale of perovskite panels, which Oxford claimed could produce up to 20% more energy than standard silicon modules.
But newer market entrants such as Cubic PV and Tandem PV are bullish on the four-terminal approach. For one, while two-terminal designs use fewer materials, they are more difficult to manufacture. Building a perovskite layer directly onto silicon’s rough surface is more technically difficult than coating it onto smooth glass, as Cubic and Tandem do. And because four-terminal companies manufacture the perovskite and silicon cells separately, they can swap in whatever silicon cell is cheapest or most efficient at any given moment, rather than being locked into a single supplier’s tech.
That flexibility could prove important as the market moves beyond early adopters. For now, Stranks said, customers buying tandem modules are probably doing so for strategic testing purposes — placing small, one-off orders to trial the tech themselves. An installer today can’t simply go buy perovskites on the open market by consulting a public pricing list or product catalogue the way they can with silicon panels. “But it’s not too far away before that would be the case,” he explained.
For its part, Swift is moving … swiftly, acquiring the manufacturing assets and IP of the bankrupt Swiss silicon cell maker Meyer Burger this spring. The company plans to use those assets first to build a U.S.-based gigawatt-scale silicon cell and module factory to meet demand for domestically manufactured solar cells, eventually adding silicon-perovskite tandem module production to that same facility.
Tandem PV is also pushing ahead with plans to begin selling to customers by the end of this year “in a volume that would be big enough to hit bankability goals,” Wharton told me. It also plans to bring a gigawatt-scale factory online by 2028. The company is targeting the independent power producers who build, own, and operate most utility-scale solar projects today. And like Oxford, Swift, and Cubic, Tandem is focused primarily on the utility-scale solar market — by far the biggest opportunity for perovskite technology.
Cubic scrapped plans in 2024 to build a facility producing silicon wafers — the raw material used to make solar cells — amid collapsing wafer prices globally and surging construction costs domestically. While Sanderson says the company remains interested in building its own factory, it has no timeline for doing so. But in the meantime, it’s also interested in licensing its IP to other perovskite companies.
The outlook for domestic wafer production has improved in recent years, though, after the Biden administration provided stronger financial incentives for producing wafers in the U.S. The Trump administration has kept these in place, though it’s made domestic content requirements stricter and more complex overall.
There’s also another new policy variable in the mix: Section 232 tariffs on cheap silicon wafers from China. Going into effect this December, the tariffs could benefit producers like Swift and Cubic, which plan to manufacture silicon cells domestically, while potentially raising costs for companies like Tandem that hope to simply source the cheapest, most efficient silicon available on the market.
At any rate, perovskites give the U.S. a chance to secure a domestic supply chain for the next wave of solar tech. Because while Chinese perovskite producers are setting efficiency records, Wharton told me that they tend to be quieter on the question of durability. That could easily give a Western producer with a credible, multi-decade warranty the opportunity to jump to the front of the pack.
And that may happen sooner than you’d expect. “This always follows the same pattern,” Wharton said of technology breakthroughs generally. “You have a bunch of early entrepreneurs who overhype things, and then everybody goes, Yeah, that was a bunch of BS. And then it actually gets real, and then people go, It’s real, but it’s going to take forever. But then it doesn’t take forever because economics always wins.”