The United States Environmental Protection Agency (EPA) is repealing rules limiting emissions by coal and gas power plants, in a move that undoes decades of protections meant to curb gasses scientists say are responsible for global warming.

“Americans have been demanding more common sense at federal agencies under President [Donald] Trump’s leadership,” EPA Administrator Lee Zeldin said at a news conference in Houston on Monday. “That means cutting red tape so we can build new power-generating infrastructure.”

The EPA estimated the changes would eliminate more than $300bn in costs for power plants. The agency also proposed a separate rule, expected to be made final next year, that could prevent future administrations from returning and again regulating greenhouse gas emissions from power plants.

The lifting of restrictions is sure to be challenged by environmental groups, who say it would come at a cost to the health of Americans and further degrade the environment. EPA officials said the change would allow utilities to make the best decisions for their ratepayers rather than be forced to close aging or inefficient plants.

“Denying the existence of a quarter of the country’s climate pollution is utterly reckless. It will lead to more lost lives and suffering from intense heatwaves, drastic storms and destructive wildfires, just like those we’ve seen this summer,” said Maggie Coulter, an attorney at the Center for Biological Diversity’s Climate Law Institute.

The EPA has rolled back a series of environmental oversight rules since US President Trump returned to office in 2025.

In February, it revoked a 2009 scientific finding that determined that carbon dioxide and other greenhouse gases threaten public health and welfare, a stance that allowed for regulation of motor vehicles, power plants and other industrial sources of air pollution.

At the time, Trump celebrated the change, calling it “the single largest deregulatory action in American history”.

Health and environmental advocacy groups filed a lawsuit challenging the revocation of that finding in February, saying it will risk the health and welfare of US citizens.

The rescinding of restrictions on coal and gas power plant emissions announced on Monday is expected to similarly be challenged in court.

“Trump wants to let power plants pollute as much as they want. This will result in serious health risks for families, our water and air, and the entire planet,” Democratic Senator Patty Murray, who represents the northwestern state of Washington, said in a statement on X. “Americans want clean air and clean water. We all need to speak up to stop this.”

The announcement on Monday was made on the sidelines of a G20 ministerial meeting in Houston on “energy abundance”. It was both a nod to the important role oil-rich Texas plays in the energy industry and a potential snub of European and other international allies in attendance who have pursued environmentally friendly policies that the Trump administration has moved to undo.

Trump called climate change “the greatest con job ever perpetrated on the world” at a speech to the United Nations last year, and his administration withdrew the US — for the second time — from the 2015 Paris climate accord that sets voluntary goals to curb planet-warming emissions.

The US president has boasted of US energy abundance even as the Iran war continues to disrupt global fuel markets and gas prices top $4.31 a gallon ($1.14 per litre), up more than a dollar from a year ago.

The rollbacks are meant to fulfill Trump’s repeated pledge to “unleash American energy” and make it easier for utilities to supply electricity for homes and businesses.

The power plant rule is among nearly three dozen environmental regulations that EPA’s Zeldin targeted in early 2025 when he announced what he called the “most consequential day of deregulation in American history”.

Zeldin said in proposing the new rules last year that they were meant to end the “war on so much of our US domestic energy supply” by former President Joe Biden and Barack Obama’s administrations.

‘Enormous costs’

Environmental and public health groups called the rollbacks dangerous and pledged to challenge the rules in court.

“Tearing down our national protections against climate pollution from power plants will have enormous costs for the health, safety and well-being of families across the country,” said Vickie Patton, general counsel for the Environmental Defense Fund. “Americans everywhere are already suffering from record-breaking heat, more dangerous floods and storms, and skyrocketing insurance costs.”

The EPA has a legal responsibility to protect the public from harmful pollution, Patton said, adding that “clean, affordable and reliable technologies are widely available to power our homes and businesses”.

Coal, gas and oil-fired power plants are responsible for about one-quarter of the nation’s total climate pollution, second only to the transportation sector. Pollution from power plants is one of the largest sources of climate-changing pollution in the world.

The rules targeted by Trump’s EPA could prevent an estimated 30,000 deaths and save $275bn each year they are in effect, according to an Associated Press analysis last year that included the agency’s own prior assessments and a wide range of other research.

Even a partial dismantling of the rules would mean more pollutants such as smog, mercury and lead — and especially more tiny airborne particles that can lodge in lungs and cause health problems, the AP analysis found. It would also mean higher emissions of greenhouse gases, driving Earth’s warming to deadlier levels.

Biden, a Democrat, had made fighting climate change a hallmark of his presidency. Coal-fired power plants would have been forced to capture smokestack emissions or shut down under a strict EPA rule issued in 2024. Those rules are now being upended.

In its proposal last year, the EPA argued that carbon dioxide and other greenhouse gases from fossil fuel-fired power plants “do not contribute significantly to dangerous pollution” or climate change and therefore do not meet a threshold under the Clean Air Act for regulatory action. Greenhouse gas emissions from coal and gas-fired plants “are a small and decreasing part of global emissions″, the EPA said.

Zeldin, a Republican and former congressman, said Biden-era actions were designed to “suffocate our economy in order to protect the environment”, with the intent to regulate the coal industry “out of existence” and make it “disappear”.

The coal industry and groups representing coal-fired power plants have denounced the Biden rule as “overreach” by the EPA and urged its repeal.

Lifting the rule will protect grid reliability and shield electricity consumers from higher costs at a time of surging demand from data centers, artificial intelligence and advanced manufacturing, according to America’s Power, a trade organisation for the US coal fleet.