AI data centers fuel electricity demand surge, reviving coal plants and reversing clean-air gains

Push to Make US Voters Love AI Gives Them New Cause to Fear It

From the White House to the statehouse, many US politicians who've been cheerleading the data-center boom are now trying to defuse a growing backlash ahead of midterm elections. But the plan they've hit on isn't winning over the skeptics. President Donald Trump and state governors like Pennsylvania Democrat Josh Shapiro are pushing the power-hungry AI facilities to buy or generate their own electricity. That's meant to assuage concern among voters about rising utility bills. It might just be giving them something else to worry about instead. Take the giant construction site at Homer City, 50 miles (80 kilometers) east of Pittsburgh. The $12 billion development is the kind of project advocated by both Trump and Shapiro, a potential presidential candidate in 2028. What was the site of the largest coal-burning plant in Pennsylvania is being redeveloped into one of the biggest natural gas plants under construction in the US, to power a roughly 1,000-acre data center campus and plenty more. Even so, there's pushback. Many people don't want to live near data centers, aren't convinced they'll provide much lasting employment, and fret that the AI bots housed within them will turn out to be job-killers. Now there are polluting emissions from on-site power plants to add to the list. It's one illustration of the broader wave of public opposition that threatens to delay or scuttle AI projects, even as they've become crucial to a US economic outlook now clouded by the Middle East war. The biggest data-center operators have lined up hundreds of billions of dollars in capital spending this year. But some local governments have moved to block large data centers, and there are bills in a dozen states to impose temporary moratoriums, according to research firm ClearView Energy Partners. Maine became the first state to pass a ban on large data-center construction this week. Analysts project that electricity prices will likely continue to rise faster than overall inflation, driven at least in part by surging AI demand -- and doubt that the bring-your-own-power plan will defuse the opposition. "I don't think that's just going to magically solve the local concerns about data centers," says Corey Young, director of the Center for Energy and the Built Environment at Washington & Jefferson College near Pittsburgh, who's worked with local governments on energy issues. Trump and Shapiro are among the leaders hoping it'll solve at least some of them. The president has championed AI. But faced with growing concerns about affordability -- especially since power prices became a hot-button issue in November's state elections -- Trump has touted the bring-your-own approach. He hosted executives from a slew of tech giants, including Meta Platforms Inc. and Microsoft Corp., and got them to sign non-binding pledges to secure electricity for their data centers. Shapiro has also been rowing back a bit. Last June, hailing an Amazon.com Inc. plan for $20 billion worth of data-center campuses, he said "the future of AI runs right through Pennsylvania." This year, acknowledging some opposition, he announced the "Governor's Responsible Infrastructure Development standards," including requirements that projects must bring or fully fund their own power generation and protect water resources. "I know Pennsylvanians have real concerns about these data centers and the impact they could have on our communities, our utility bills, and our environment," he said in his Feb. 3 budget address. "And so do I." At Homer City, which could eventually have one of the biggest data-center campuses in Pennsylvania and perhaps the whole country, building is well underway. The 3,200-acre site -- where demolition of the old power plant, with smokestacks and cooling towers that were a local landmark, began about a year ago -- is bustling with more than 1,000 construction workers. Homer City Redevelopment and Kiewit Power Constructors Co. have removed 93,000 tons of material from demolition of the old plant, and they erected the first steel for the new facility recently. Talks are in progress with potential customers like data centers or advanced manufacturers who would build on the site, says Chief Executive Officer Corey Hessen. A new treatment facility is being built for the cooling water they'll need. As for power, the goal is to hook up the first two of seven GE Vernova turbines to the grid in the second quarter of 2028. The plant will provide about 3,700 megawatts to the energy campus -- substantially more than the peak load last year for the entire Pittsburgh area -- and still have some 800 megawatts to spare for the local grid, enough to power 800,000 homes, Hessen says. "We're bringing our own power and then some," he says. "That, I think, meets the expectations of the national and the state and the local communities of what this project can and should be." There's local backing for the project because this corner of western Pennsylvania has been desperate to attract jobs lost when the coal mines closed and manufacturers left, says Homer City Borough Mayor Kyle Cobaugh. "I think it is going to be good for our area," Cobaugh says. "It's going to bring in the hopefully right people, the right jobs and help re-stimulate our area." A study by industry groups argues that Pennsylvania data centers will add $12 billion in annual economic output and support almost 20,000 jobs by 2036. Across Pennsylvania, though, a Quinnipiac University poll in February found that 68% of voters would oppose having a data center in their community. The environmental group PennFuture has called for a statewide moratorium until stricter regulations are adopted. It's also one of the groups appealing the commonwealth's approval of an air permit for the Homer City natural gas plant. Concerned Residents of Western PA is another group fighting the project -- imploring local officials to revoke permits and enact a moratorium on data center development because of concerns about emissions and pollution. "Given the scale of negative impacts we will experience, we must act now," Indiana County resident Susan Comfort told county commissioners at a March 25 meeting. While some of those impacts only affect people living near the projects, higher power prices hit more broadly. Households have already gotten squeezed. In Pennsylvania, the average monthly bill has climbed by about 30% since 2020, to between $150 and $160, according to the state's Office of Consumer Advocate. There are other reasons besides data centers. Still, the giant grid operator PJM, which handles wholesale markets in Pennsylvania and a dozen other states -- covering almost one-fifth of the US population -- has been challenged by the takeoff of AI and resulting spike in power demand. At three auctions held since mid-2024 to pay generators to be maintained and ready to serve, the cost soared by more than $23 billion because of data centers alone, which accounted for 49% of the total supply procured. That's effectively baking in more hikes to consumer bills. Goldman Sachs analysts expect data centers to account for about 40% of overall US power demand growth over the next five years. That will likely keep electricity inflation at around 6% through at least 2027, and it could go higher if the AI companies don't help out enough with the needed capacity boost, they wrote. Plans like the ones backed by Trump and Shapiro aim to ensure that they do. While there are doubts about how it'll work in practice, many tech firms say they're on board with the idea, partly because having their own electricity sources can help accelerate projects. What's known as "speed to power" in the industry jargon is becoming a decisive factor for data centers. It can take three years or longer to connect to the grid in many parts of the country, said Holly Lahd, a managing director at consultant CBRE Energy. By contrast, it took Elon Musk's xAI just 122 days to develop its Colossus data center in Tennessee, using portable gas generators. But that project has triggered complaints about pollution, legal challenges to the permitting process, and a probe by Senate Democrats. At some data centers, developers are bringing their own power by building on-site power generation that's completely off the electricity grid, unlike the Homer City project. A drawback of that model is that it narrows the customer base for local grids, leaving them short of cash to invest in aging systems, according to Jigar Shah at advisory firm Multiplier, who was a senior energy official in the Biden administration. "You end up with something more rickety that has more outages," he says. While access to power has been the biggest roadblock for data-center investors, NIMBYism is swiftly moving up to No. 2, says S&P Global analyst Brian Partridge. He expects about one-fourth of all US data centers built by 2030 will have on-site power, and is tracking some 130 gigawatts of such projects - roughly equal 10% of current US generating capacity - though he cautions that 30 gigawatts are likely mere "dreams." If that estimate is correct, it leaves a lot of data centers that won't be generating their own power. And beyond AI there are other pressures pointing to higher prices, on both the supply and demand side, like the electrification of transportation and home heating, or the fragmentation of US grids. At a couple of recent energy finance conferences, bankers worried aloud that surging data-center demand will pressure household bills and shift the economics of new projects. All this means that "bring your own" plans won't address the root problem of stopping the rise in electricity prices, according to Michael Thomas, founder of energy data company Cleanview. "If that's the only thing that we do," he says, "you're going to have a lot of angry people in two years who say, 'Hey, my electricity bill is 25%, 50% higher.'"

How the AI boom derailed clean‑air efforts in one of America's most polluted cities

April 10 (Reuters) - Barbara Johnson has been fighting coal pollution for decades in her mostly Black neighborhood of North St. Louis as an organizer with Metropolitan Congregations United - one of many activist groups campaigning for cleaner air in a city that has some of the country's dirtiest. Until recently, Johnson had reason to believe things would improve: tougher federal soot standards adopted in 2024 under the Biden administration were scheduled to go into effect in 2027, requiring plants to slash emissions or shut down. That would have forced one of the area's biggest polluters - Ameren's Labadie Energy Center power plant - to cut its soot emissions in half to stay in business. Johnson's hopes vanished in February, however, when President Donald Trump's administration scrapped the standards before they took effect as part of broader efforts to ensure the nation's grid can meet surging demand from data centers. Now she wonders if she'll ever get to see the changes she's been fighting for since her youth. "You take two steps forward and four steps back," said Johnson, 75. "I am used to that backwards trend but how many generations will it take to make those positive changes stick?" Trump's rollbacks in support of AI mark a reversal in U.S. environmental policy and a painful truth for America's clean air activists: After years pushing coal toward the exits, the rise of power-hungry data centers has nudged the country's most polluting power source back to the stage. Trump last year issued an executive order entitled "Reinvigorating America's Beautiful Clean Coal Industry", opens new tab that said coal-fired power was crucial to meeting the rise in U.S. electricity demand driven by the construction of artificial intelligence data processing centers. He has since provided funding to keep old plants running, issued orders to delay plant retirements, and rolled back environmental regulations on mercury and other toxins to free plants from costly upgrades. "Ensuring affordable baseload power, including coal, is essential for keeping the lights on and heating American homes," the U.S. Environmental Protection Agency said in an emailed statement about the regulatory rollbacks. "EPA is committed to ensuring clean air for all Americans regardless of race, gender, creed, or background." The U.S. Department of Energy estimates artificial intelligence and data‑center growth will create 50 gigawatts of new electricity demand by 2030 - a nearly 4% increase over the 1,300 gigawatts produced by all U.S. power plants in 2025. Reuters interviewed 20 air quality activists and health advocates for this story and found all had identified the AI boom - and the policies supporting it - ⁠as the biggest potential threat to U.S. air quality due to its need for power, including from dirty sources like coal. Over the past decade, the number of U.S. coal plants providing energy to the grid and other industrial operations dropped to about 200 from nearly 400 in 2015, according to EPA data examined by Reuters. But that pace has slowed fast. In 2025 only four plants producing 2.6 gigawatts were retired, compared with 94 producing 15 gigawatts in 2015, as the DOE issued emergency orders keeping them online, according to the U.S. Energy Information Administration. A coalition of farmers, environmentalists and homeowners have united to resist data-center expansion out of concern for its impacts, ranging from higher power bills to reduced water supplies - a potential liability for Republicans in the November midterm elections. Trump has since secured voluntary agreements from big tech companies to pay up for their power needs and shield American consumers from higher bills, but his administration has not announced steps to address the health effects of higher pollution from expanded power generation. St. Louis will be among the U.S. cities most impacted by the regulatory rollbacks, mainly because of its already poor air quality and the close proximity of the huge Labadie plant, according to the interviews, and government data reviewed by Reuters. Last year, metro St. Louis residents had "good" air to breathe during only one-third of the days of the year, according to the standards used by the EPA's Air Quality Index. That ranked St. Louis 475th in air quality out of 501 small and large U.S. metro areas. The Labadie Energy Center is a significant contributor, according to EPA data and recent scientific studies, opens new tab. The plant, a sprawling facility that sits around 40 miles to the city's west, produces the highest combined total of sulfur dioxide and nitrogen oxides among U.S. coal plants, and also emits soot at a rate that is two to three times that of nearly every other U.S. coal plant, according to EPA data. That pollution drives an estimated economic burden of up to $5.5 billion each year, with about $820 million of those costs borne by St. Louis area residents, according to a Reuters analysis of the EPA's Co-Benefits Risk Assessment (COBRA) tool. COBRA estimates health costs such as emergency room visits and measures how much people, collectively, are willing to pay for cleaner air because it lowers the risk of premature death. Reuters showed the analysis to two outside experts - Bryan Hubbel, a senior fellow at non-profit research group Resources for the Future and John Graham, a senior scientist at the environmental research group Clean Air Task Force - who both agreed with the figures. Labadie's owner, St. Louis-based ⁠utility Ameren Corp , did not contest the Reuters analysis of the EPA data. Ameren said the plant operates within the existing federal pollution limits. Labadie will keep running for at least another decade as demand from artificial intelligence-driven data centers outpaces the rollout of cleaner power, Ameren said. "Our employees live here, raise families here and rely on the same energy as our neighbors," Craig Giesman, Ameren's director of environmental services, said in a statement. "That is just one of many reasons we remain focused on operating responsibly, protecting public health and providing reliable energy, especially when it's needed most." The EPA declined to comment on Reuters' analysis of the COBRA data, but pointed out the agency is seeking to update its cost-benefit modeling tools. A scientific study led by researchers at the University of Washington and published in the Journal of the International Society for Environmental Epidemiology last year said St. Louis would be the city most impacted by delaying tougher soot standards on U.S. coal plants. Biden's regulation would have forced Labadie to slash its soot emissions by more than half to continue to operate. Those soot limits would have yielded net public health benefits of up to $3 billion, opens new tab nationwide by 2037, according to the EPA's 2023 cost-benefit analysis. The EPA under Trump has since reversed course. The agency told Reuters the Biden administration's estimates were overblown and that existing standards provide "an ample margin of safety to protect public health." St. Louis clean ⁠air activists see it differently. "Our region continues to be a sacrifice zone," said Darnell Tingle, director of United Congregations of Metro-East, another activist network. "We are trying to prepare for these data centers, and negate their harm to our communities." CHEAP POWER The predominantly Black neighborhoods of North St. Louis already have some of the city's worst air quality. Tiny particles of soot pollution small enough to penetrate the brain and lungs exceed federal safety limits there regularly, according to a Reuters analysis of data tracked by the EPA, thanks to industrial sources along with pollution from nearby highways and rail operations. Some 78% of African Americans live within 30 miles of a coal-fired power plant, according to the NAACP, compared to 56% of non-Hispanic whites. Soot pollution from power plants, meanwhile, kills African Americans at a rate that is 25% higher than the national average, according to a 2019 study in the Environmental Science & Technology journal. "The logic is that we need ⁠cheap electricity in the U.S. But if you look at the rise in healthcare costs for residents in the St. Louis area, this isn't cheap," said Patricia Schuba, who runs a local environmental group that monitors Labadie and three other coal plants. Tougher pollution limits had forced Ameren to upgrade Labadie. About a decade ago, Ameren installed state-of-the-art soot pollution controls for two of Labadie's four coal-fired boilers in order to comply with Obama-era soot limits. At a minimum, older controls on the remaining boilers would have needed retrofitting to meet Biden‑era limits, Ameren told the EPA in a March 2025 letter seeking an exemption. Ameren declined to answer questions about how much upgrading the plant would have cost. Meanwhile, data‑center developers are breaking ground on major projects around St. Louis, pushing up regional electricity demand. Ameren has said it has signed service contracts for an additional 2.3 ⁠gigawatts of potential peak demand from data centers - roughly the output of the Labadie plant - and that more requests are coming. One of the biggest upcoming data center projects is a 1,000-acre development by Amazon Web Services proposed for rural Montgomery County, about 55 miles from Labadie. The power would be supplied by Ameren. Amazon declined to comment. The data center industry's trade group - the Data Center Coalition - said its member companies were among the top purchasers of clean energy but that utilities, regulators and grid operators are ultimately responsible for the kinds of power generation being used by consumers. "While the data center industry is leaning in to support the development of the 21st-century electrical grid, it's important to recognize that resource planning and generation procurement decisions are made by utilities, grid operators, and policymakers, not large load customers like data centers," said Lucas Fykes, Senior Director of Energy Policy and Regulatory Counsel at the coalition. Reporting by Valerie Volcovici and Tim McLaughlin; editing by Richard Valdmanis, Michael Learmonth and Frank Jack Daniel Our Standards: The Thomson Reuters Trust Principles., opens new tab * Suggested Topics: * Climate & Energy * Climate Change * Healthcare Providers * Lawsuits Valerie Volcovici Thomson Reuters Valerie Volcovici covers U.S. climate and energy policy from Washington, DC. She is focused on climate and environmental regulations at federal agencies and in Congress and how the energy transition is transforming the United States. Other areas of coverage include her award-winning reporting plastic pollution and the ins and outs of global climate diplomacy and United Nations climate negotiations.

How the AI Boom Derailed Clean‑air Efforts in One of America's Most Polluted Cities

By Valerie Volcovici and Tim McLaughlin April 10 (Reuters) - Barbara Johnson has been fighting coal pollution for decades in her mostly Black neighborhood of North St. Louis as an organizer with Metropolitan Congregations United - one of many ⁠activist groups ⁠campaigning for cleaner air in a city that has some of the country's dirtiest. Until recently, Johnson had reason to ⁠believe things would improve: tougher federal soot standards adopted in 2024 under the Biden administration were scheduled to go into effect in 2027, requiring plants to slash emissions or shut down. That would have forced one of the area's biggest polluters - Ameren's Labadie Energy Center power plant - to cut its soot emissions in half to stay in business. Johnson's hopes vanished in February, however, when President Donald Trump's administration scrapped the standards before they took effect as part of broader efforts to ensure the nation's grid can meet surging demand from data centers. Now she wonders if she'll ever get to see the changes she's been fighting for since her youth. "You take two steps forward and four steps back," said Johnson, 75. "I am used to that backwards trend but how many generations will it take to make those positive changes stick?" Trump's rollbacks in support of AI mark a reversal in U.S. environmental policy and a painful truth for America's clean air activists: After years pushing coal toward the exits, the rise of power-hungry data centers has nudged the country's most polluting power source back to the stage. Trump last year issued an executive order entitled "Reinvigorating America's Beautiful Clean Coal Industry" that said coal-fired power was crucial to meeting the rise in U.S. electricity demand driven by the construction of artificial ⁠intelligence data processing centers. He has since provided funding ⁠to keep old plants running, issued orders to delay plant retirements, and rolled back environmental regulations on mercury and other toxins to free plants from costly upgrades. "Ensuring affordable baseload power, including coal, is essential for keeping the lights on and heating American homes," the U.S. Environmental Protection Agency said in an emailed statement about the regulatory rollbacks. "EPA is committed to ensuring clean air for all Americans regardless of race, gender, creed, or background." The U.S. Department of Energy estimates artificial intelligence and data‑center growth will create 50 gigawatts of new electricity demand by 2030 - a nearly 4% increase over the 1,300 gigawatts produced by all U.S. power plants in 2025. Reuters interviewed 20 air quality activists and health advocates for this story and found all had identified the AI boom - and the policies supporting it - as the biggest potential threat to U.S. air quality due to its need for power, including from dirty sources like coal. Over the past decade, the number of U.S. coal plants providing energy to the grid and other industrial operations dropped to about 200 from nearly 400 in 2015, according to EPA data examined by Reuters. But that pace has slowed fast. In 2025 only four plants producing 2.6 gigawatts were retired, compared with 94 producing 15 gigawatts in 2015, as the DOE issued emergency orders keeping them online, according to the U.S. Energy Information Administration. A coalition of farmers, environmentalists and homeowners have united to resist data-center expansion out of concern for its impacts, ranging from higher power bills to reduced water supplies - a potential liability ⁠for ⁠Republicans in the November midterm elections. Trump has since secured voluntary agreements from big ⁠tech companies to pay up for their power needs and shield American consumers from higher bills, but his administration has not announced steps to address the health effects of higher pollution from expanded power generation. St. Louis will be among the U.S. cities most impacted by the regulatory rollbacks, mainly because of its already poor air quality and the close proximity of the huge Labadie plant, according to the interviews, and government data reviewed by Reuters. Last year, metro St. Louis residents had "good" air to breathe during only one-third of the days ⁠of the year, according to the standards used by the EPA's Air Quality Index. That ranked St. Louis 475th in air quality out of 501 small and large U.S. metro areas. The Labadie Energy Center is a significant contributor, according to EPA data and recent scientific studies. The plant, a sprawling facility that sits around 40 miles to the city's west, produces the highest combined total of sulfur dioxide and nitrogen oxides among U.S. coal plants, and also emits soot at a rate that is two to three times that of nearly every other U.S. coal plant, according to EPA data. That pollution drives an estimated economic burden of up to $5.5 billion each year, with about $820 million of those costs borne by St. Louis area residents, according to a Reuters analysis of the EPA's Co-Benefits Risk Assessment (COBRA) tool. COBRA estimates health costs such as emergency room visits and measures how much people, collectively, are willing to pay for cleaner air because it lowers the risk of premature death. Reuters showed the analysis to two outside experts - Bryan Hubbel, a senior fellow at non-profit research group Resources for the Future and John Graham, a senior scientist at the environmental research group Clean Air Task Force - who both agreed with the figures. Labadie's owner, St. Louis-based utility Ameren Corp, did not contest the Reuters analysis of the EPA data. Ameren said the plant operates within the existing ⁠federal pollution limits. Labadie will keep running for at least another decade as demand from artificial intelligence-driven data centers outpaces the rollout of cleaner power, Ameren said. "Our employees live here, raise families here and rely on the same energy as our neighbors," Craig Giesman, Ameren's ⁠director of environmental services, said in a statement. "That is just one of many reasons we remain focused on operating responsibly, protecting public health and providing reliable energy, especially when it's needed most." The EPA declined to comment on Reuters' analysis of the COBRA data, but pointed out the agency is seeking to update its cost-benefit modeling tools. A scientific study led by researchers at the University of Washington and published in the Journal of the International Society for Environmental Epidemiology last year said St. Louis would be the city most impacted by delaying tougher soot standards on U.S. coal plants. Biden's regulation would have forced Labadie to slash its soot emissions by more than half to continue to operate. Those soot limits would have yielded net public health benefits of up to $3 billion nationwide by 2037, according to the EPA's 2023 cost-benefit analysis. The EPA under Trump has since reversed course. The agency told Reuters the Biden administration's estimates were overblown and that existing standards provide "an ample margin of safety to protect public health." St. Louis clean air activists see it differently. "Our region continues to be a sacrifice zone," said Darnell Tingle, director of United Congregations of Metro-East, another activist network. "We are trying to prepare for these data centers, and negate their harm to our communities." CHEAP POWER The predominantly Black neighborhoods of North St. Louis already have some of the city's worst air quality. Tiny particles of soot pollution small enough to penetrate the brain and lungs exceed federal safety limits there regularly, according to a Reuters analysis of data tracked by the EPA, thanks to industrial sources along with pollution from nearby highways and rail operations. Some 78% of African Americans live within 30 miles of a coal-fired power plant, according to the NAACP, compared to 56% of non-Hispanic whites. Soot pollution from power plants, meanwhile, kills African Americans at a rate that is 25% higher than the national average, according to a 2019 study in the Environmental Science & Technology journal. "The logic is that we need cheap electricity in the U.S. But if you look at the rise in healthcare costs for residents in the St. Louis area, this isn't cheap," said Patricia Schuba, who runs a local environmental group that monitors Labadie and three other coal plants. Tougher pollution limits had forced Ameren ⁠to upgrade Labadie. About a decade ago, Ameren installed state-of-the-art soot pollution controls for two of Labadie's four coal-fired boilers in order to comply with Obama-era soot limits. At a minimum, older controls on the remaining boilers would have needed retrofitting to meet Biden‑era limits, Ameren told the EPA in a March 2025 letter seeking an exemption. Ameren declined to answer questions about how much upgrading the plant would have cost. Meanwhile, data‑center developers are breaking ground on major projects around St. Louis, pushing up regional electricity demand. Ameren has said it has signed service contracts for an additional 2.3 gigawatts of potential peak demand from data centers - roughly the output of the Labadie plant - and that more requests are coming. One of the biggest upcoming data center projects is a 1,000-acre development by Amazon Web Services proposed for rural Montgomery County, about 55 miles from Labadie. The power would be supplied by Ameren. Amazon declined to comment. The data center industry's trade group - the Data Center Coalition - said its member companies were among the top purchasers of clean energy but that utilities, regulators and grid operators are ultimately responsible for the kinds of power generation being used by consumers. "While the data center industry is leaning in to support the development of the 21st-century electrical grid, it's important to recognize that resource planning and generation procurement decisions are made by utilities, grid operators, and policymakers, not large load customers like data centers," said Lucas Fykes, Senior Director of Energy Policy and Regulatory Counsel at the coalition. (Reporting by Valerie Volcovici and Tim McLaughlin; editing by Richard Valdmanis, Michael Learmonth and Frank Jack Daniel)

How the AI boom derailed clean‑air efforts in one of America's most polluted cities

America's push for cleaner air faces a new challenge. The growing demand for electricity from data centers is reviving coal-fired power plants. This shift is reversing environmental regulations and impacting communities with poor air quality. Activists are concerned about the long-term health effects. The future of clean air hangs in the balance as energy needs surge. Barbara Johnson has been fighting coal pollution for decades in her mostly Black neighborhood of North St. Louis as an organiser with Metropolitan Congregations United - one of many activist groups campaigning for cleaner air in a city that has some of the country's dirtiest. Until recently, Johnson had reason to believe things would improve: tougher federal soot standards adopted in 2024 under the Biden administration were scheduled to go into effect in 2027, requiring plants to slash emissions or shut down. That would have forced one of the area's biggest polluters - Ameren's Labadie Energy Center power plant - to cut its soot emissions in half to stay in business. Johnson's hopes vanished in February, however, when President Donald Trump's administration scrapped the standards before they took effect as part of broader efforts to ensure the nation's grid can meet surging demand from data centers. Now she wonders if she'll ever get to see the changes she's been fighting for since her youth. "You take two steps forward and four steps back," said Johnson, 75. "I am used to that backwards trend but how many generations will it take to make those positive changes stick?" Trump's rollbacks in support of AI mark a reversal in U.S. environmental policy and a painful truth for America's clean air activists: After years pushing coal toward the exits, the rise of power-hungry data centers has nudged the country's most polluting power source back to the stage. Trump last year issued an executive order entitled "Reinvigorating America's Beautiful ⁠Clean Coal Industry" ⁠that said coal-fired power was crucial to meeting the rise in US electricity demand driven by the construction of artificial intelligence data processing centers. He has since provided funding to keep old plants running, issued orders to delay plant retirements, and rolled back environmental regulations on mercury and other toxins to free plants from costly upgrades. "Ensuring affordable baseload power, including coal, is essential for keeping the lights on and heating American homes," the U.S. Environmental Protection Agency said in an emailed statement about the regulatory rollbacks. "EPA is committed to ensuring clean air for all Americans regardless of race, gender, creed, or background." The U.S. Department of Energy estimates artificial intelligence and data-center growth will create 50 gigawatts of new electricity demand by 2030 - a nearly 4% increase over the 1,300 gigawatts produced by all U.S. power plants in 2025. Reuters interviewed 20 air quality activists and health advocates for this story and found all had identified the AI boom - and the policies supporting it - as the biggest potential threat to U.S. air quality due to its need for power, including from dirty sources like coal. Over the past decade, the number of U.S. coal plants providing energy to the grid and other industrial operations dropped to about 200 from nearly 400 in 2015, according to EPA data examined by Reuters. But that pace has slowed fast. In 2025 only four plants producing 2.6 gigawatts were retired, compared with 94 producing 15 gigawatts in 2015, as the DOE issued emergency orders keeping them online, according to the U.S. Energy Information Administration. A coalition of farmers, environmentalists and homeowners have united to resist data-center expansion out of concern for its impacts, ranging from higher power bills to reduced water supplies - a potential liability for Republicans in the November midterm elections. Trump has since secured voluntary agreements from big tech companies to pay up for their power needs and shield American consumers from higher bills, but his ⁠administration has not announced steps to address the health effects of higher pollution from expanded power generation. St. Louis will be among the U.S. cities most impacted by the regulatory rollbacks, mainly because of its already poor air quality and the close proximity of the huge Labadie plant, according to the interviews, and government data reviewed by Reuters. Last year, metro St. Louis residents had "good" air to breathe during only one-third of the days of the year, according to the standards used by the EPA's Air Quality Index. That ranked St. Louis 475th in air quality out of 501 small and large U.S. metro areas. The Labadie Energy Center is a significant contributor, according to ⁠EPA data and recent scientific studies. The plant, a sprawling facility that sits around 40 miles to the city's west, produces the highest combined total of sulfur dioxide and nitrogen oxides among U.S. coal plants, and also emits soot at a rate that is two to three times that of nearly every other U.S. coal plant, according to EPA data. That pollution drives an estimated economic burden of up to $5.5 billion each year, with about $820 million of those costs borne by St. Louis area residents, according to a Reuters analysis of the EPA's Co-Benefits Risk Assessment (COBRA) tool. COBRA estimates health costs such as emergency room visits and measures how much people, collectively, are willing to pay for cleaner air because it lowers the risk of premature death. Reuters showed the analysis to two outside experts - Bryan Hubbel, a senior fellow at non-profit research group Resources for the Future and John Graham, a senior scientist at the environmental research group Clean Air Task Force - who both agreed with the figures. Labadie's owner, St. Louis-based utility Ameren Corp, did not contest the Reuters analysis of the EPA data. Ameren said the plant operates within the existing federal pollution limits. Labadie will keep running for at least another decade as demand from artificial intelligence-driven data centers outpaces the rollout of cleaner power, Ameren said. "Our employees live here, raise families here and rely on the same energy as our neighbors," Craig Giesman, Ameren's director of environmental services, said in a statement. "That is just one of many reasons we remain focused on operating responsibly, protecting public health and providing reliable energy, especially when it's needed most." The EPA declined to comment on Reuters' analysis of the COBRA data, but pointed out the agency is seeking to update its cost-benefit modeling tools. A scientific study led by researchers at the University of Washington and published in the Journal of the International Society for Environmental Epidemiology last year said St. Louis would be the city most impacted by delaying tougher soot standards on U.S. coal plants. Biden's regulation would have forced Labadie to slash its soot emissions by more than half to continue to operate. Those soot limits would have yielded net public health benefits of up to $3 billion nationwide by 2037, according to the EPA's 2023 cost-benefit analysis. The EPA under Trump has since reversed course. The agency told Reuters the Biden administration's estimates were overblown and that existing standards provide "an ample margin of safety to protect public health." St. Louis clean air activists see it differently. "Our region continues to be a sacrifice zone," said Darnell Tingle, director of United Congregations of Metro-East, another activist network. "We are trying to prepare for these data centers, and negate their harm to our communities." Cheap power The predominantly Black neighborhoods of North St. Louis already have some of the ⁠city's worst air quality. Tiny particles of soot pollution small enough to penetrate the brain and lungs exceed federal safety limits there regularly, according to a Reuters analysis of data tracked by the EPA, thanks to industrial sources along with pollution from nearby highways and rail operations. Some 78% of African Americans live within 30 miles of a coal-fired power plant, according to the NAACP, compared to 56% of non-Hispanic whites. Soot pollution from power plants, meanwhile, kills African Americans at a rate that is 25% higher than the national average, according to a 2019 study in the Environmental Science & Technology journal. "The logic is that we need cheap electricity in the U.S. But if you look at the rise in healthcare costs for residents in the St. Louis area, this isn't cheap," said Patricia Schuba, who runs a local environmental group that monitors Labadie and three other coal plants. Tougher pollution limits had forced Ameren to upgrade Labadie. About a decade ago, Ameren installed state-of-the-art soot pollution controls for two of Labadie's four coal-fired boilers in order to comply with Obama-era soot limits. At a minimum, older controls on the remaining boilers would have needed retrofitting to meet Biden-era limits, Ameren told the EPA in a March 2025 letter seeking an exemption. Ameren declined to answer questions about how much upgrading the plant would have cost. Meanwhile, data-center developers are breaking ground on major projects around St. Louis, pushing up regional electricity demand. Ameren has said it has signed service contracts for an additional 2.3 gigawatts of potential peak demand from data centers - roughly the output of the Labadie plant - and that more requests are coming. One of the biggest upcoming data center projects is a 1,000-acre development by Amazon Web Services proposed for rural Montgomery County, about 55 miles from Labadie. The power would be supplied by Ameren. Amazon declined to comment. The data center industry's trade group - the Data Center Coalition - said its member companies were among the top purchasers of clean energy but that utilities, regulators and grid operators are ultimately responsible for the kinds of power generation being used by consumers. "While the data center industry is leaning in to support the development of the 21st-century electrical grid, it's important to recognize that resource planning and generation procurement decisions are made by utilities, grid operators, and policymakers, not large load customers like data centers," said Lucas Fykes, Senior Director of Energy Policy and Regulatory Counsel at the coalition.

How the AI boom derailed clean‑air efforts in one of America's most polluted cities

Barbara Johnson has been fighting coal pollution for decades in her mostly Black neighborhood of North St. Louis, Missouri, as an organizer with Metropolitan ⁠Congregations United -- one of many activist groups campaigning for cleaner air in a city that has some of the dirtiest air in the United States. Until recently, Johnson had reason to believe things would improve: tougher federal soot standards adopted in 2024 under the administration of U.S. President Joe Biden were scheduled to go into effect in 2027, requiring plants to slash emissions or shut down. That would have forced one of the area's biggest polluters -- Ameren's Labadie Energy Center power plant -- to cut its soot emissions in half to stay in business. Johnson's hopes vanished in February, however, when President Donald Trump's administration scrapped the standards before they took effect as part of broader efforts to ensure the nation's grid can meet surging demand from data centers. Now she wonders if she'll ever get to see the changes she's been fighting for since her youth. "You take two steps forward and four steps back," said Johnson, 75. "I am used to that backwards trend but how many generations will it take to make those positive changes stick?" Trump's rollbacks in support of artificial intelligence mark a reversal in U.S. environmental policy and a painful truth for America's clean air activists: After years pushing coal toward the exits, the rise of power-hungry data centers has nudged the country's most polluting power source back to the stage. Trump last year issued an executive order entitled "Reinvigorating America's Beautiful Clean Coal Industry" that said coal-fired power was crucial to meeting the rise in U.S. electricity demand driven by the construction of artificial intelligence data processing centers. He has since provided funding to keep old plants running, issued orders to delay plant retirements, and rolled back environmental regulations on mercury and other toxins to free plants from costly upgrades. "Ensuring affordable baseload power, including coal, is essential for keeping the lights on and heating American homes," the U.S. Environmental Protection Agency said in an emailed statement about the regulatory rollbacks. "EPA is committed to ensuring clean air for all Americans regardless of race, gender, creed, or background." The U.S. Department of Energy estimates artificial intelligence and data-center growth will create 50 gigawatts of new electricity demand by 2030 -- a nearly 4% increase over the 1,300 gigawatts produced by all U.S. power plants in 2025. Twenty air quality activists and health advocates were interviewed for this story and all identified the ⁠AI boom -- and the policies supporting it -- as the biggest potential threat to U.S. air quality due to its need for power, including from dirty sources like coal. Over the past decade, the number of U.S. coal plants providing energy to the grid and other industrial operations dropped to about 200 from nearly 400 in 2015, according to EPA data. But that pace has slowed fast. In 2025 only four plants producing 2.6 gigawatts were retired, compared with 94 producing 15 gigawatts in 2015, as the DOE issued emergency orders keeping them online, according to the U.S. Energy Information Administration. A coalition of farmers, environmentalists and homeowners have united to resist data-center expansion out of concern for its impacts, ranging from higher power bills to reduced water supplies -- a potential liability for Republicans in the November midterm elections. Trump has since secured voluntary agreements from big tech companies to pay up for their power needs and shield American consumers from higher bills, but his administration has not announced steps to address the health effects of higher pollution ⁠from expanded power generation. St. Louis will be among the U.S. cities most impacted by the regulatory rollbacks, mainly because of its already poor air quality and the close proximity of the huge Labadie plant, according to the interviews and government data. Last year, metro St. Louis residents had "good" air to breathe during only one-third of the days of the year, according to the standards used by the EPA's Air Quality Index. That ranked St. Louis 475th in air ⁠quality out of 501 small and large U.S. metro areas. The Labadie Energy Center is a significant contributor, according to EPA data and recent scientific studies. The plant, a sprawling facility that sits around 65 kilometers to the city's west, produces the highest combined total of sulfur dioxide and nitrogen oxides among U.S. coal plants, and also emits soot at a rate that is two to three times that of nearly every other U.S. coal plant, according to EPA data. That pollution drives an estimated economic burden of up to $5.5 billion each year, with about $820 million of those costs borne by St. Louis area residents, according to an analysis of the EPA's Co-Benefits Risk Assessment (COBRA) tool. COBRA estimates health costs such as emergency room visits and measures how much people, collectively, are willing to pay for cleaner air because it lowers the risk of premature death. The analysis was presented to two outside experts -- Bryan Hubbel, a senior fellow at nonprofit research group Resources for the Future and John Graham, a senior scientist at the environmental research group Clean Air Task Force -- who both agreed with the figures. Labadie's owner, St. Louis-based utility Ameren, did not contest the analysis of the EPA data. Ameren said the plant operates within the existing federal pollution limits. Labadie will keep running for at least another decade as demand from artificial intelligence-driven data centers outpaces the rollout of cleaner power, Ameren said. "Our employees live here, raise families here and rely on the same energy as our neighbors," Craig Giesman, Ameren's director of environmental services, said in a statement. "That is just one of many reasons we remain focused on operating responsibly, protecting public health and providing reliable energy, especially when it's needed most." The EPA declined to comment on Reuters' analysis of the COBRA data, but pointed out the agency is seeking to update its cost-benefit modeling tools. A scientific study led by researchers at the University of Washington and published in the Journal of the International Society for Environmental Epidemiology last year said St. Louis would be the city most impacted by delaying tougher soot standards on U.S. coal plants. Biden's regulation would have forced Labadie to slash its soot emissions by more than half to continue to operate. Those soot limits would have yielded net public health benefits of up to $3 billion nationwide by 2037, according to the EPA's 2023 cost-benefit analysis. The EPA under Trump has since reversed course. The agency said the Biden administration's estimates were overblown and that existing standards provide "an ample margin of safety to protect public health." St. Louis clean air activists see it differently. "Our region continues to be a sacrifice zone," said Darnell Tingle, director of United Congregations of Metro-East, another activist network. "We are trying to prepare for these data centers, and negate their harm to our communities." The predominantly Black neighborhoods of North St. Louis already have some of the city's worst air quality. Tiny particles of soot pollution small enough to penetrate the brain and lungs exceed federal safety limits there regularly, according to an analysis of data tracked by the EPA, thanks to industrial sources along with pollution from nearby highways and rail operations. Some 78% of African Americans live ⁠within 50 kilometers of a coal-fired power plant, according to the NAACP, compared to 56% of non-Hispanic whites. Soot pollution from power plants, meanwhile, kills African Americans at a rate that is 25% higher than the national average, according to a 2019 study in the Environmental Science & Technology journal. "The logic is that we need cheap electricity in the U.S. But if you look at the rise in health care costs for residents in the St. Louis area, this isn't cheap," said Patricia Schuba, who runs a local environmental group that monitors Labadie and three other coal plants. Tougher pollution limits had forced Ameren to upgrade Labadie. About a decade ago, Ameren installed state-of-the-art soot pollution controls for two of Labadie's four coal-fired boilers in order to comply with Barack Obama-era soot limits. At a minimum, older controls on the remaining boilers would have needed retrofitting to meet Biden-era limits, Ameren told the EPA in a March 2025 letter seeking an exemption. Ameren declined to answer questions about how much upgrading the plant would have cost. Meanwhile, data-center developers are breaking ground on major projects around St. Louis, pushing up regional electricity demand. Ameren has said it has signed service contracts for an additional 2.3 gigawatts of potential peak demand from data centers -- roughly the output of the Labadie plant -- and that more requests are coming. One of the biggest upcoming data center projects is a 400-hectare development by Amazon Web Services proposed for rural Montgomery County, about 90 kilometers from Labadie. The power would be supplied by Ameren. Amazon declined to comment. The data center industry's trade group -- the Data Center Coalition -- said its member companies were among the top purchasers of clean energy but that utilities, regulators and grid operators are ultimately responsible for the kinds of power generation being used by consumers. "While the data center industry is leaning in to support the development of the 21st-century electrical grid, it's important to recognize that resource planning and generation procurement decisions are made by utilities, grid operators, and policymakers, not large load customers like data centers," said Lucas Fykes, senior director of energy policy and regulatory counsel at the coalition.