On the heels of the hottest summer ever recorded in the US, the Trump administration has said it will erase any limits on emissions from coal and gas plants that are dangerously heating up our planet.

The US Environmental Protection Agency said it will strip itself of its ability to regulate greenhouse gas emissions coming from power plants under the Clean Air Act, removing a key tool to address the climate crisis.

By erasing any limits on such emissions from coal and gas plants, the Trump administration has severely limited any future administration’s ability to curb this pollution.

The EPA calculated the move will result in 123m metric tons of additional carbon emissions in the next decade, and save power plant operators $370m in direct compliance costs. Lee Zeldin, the agency administrator said the Trump administration is protecting American energy from a “war on coal”.

“Americans will see a decrease in electricity prices, but this is just the beginning,” said Zeldin, who unveiled the reversal of the 2024 carbon pollution standards at a G20 meeting in Houston on Monday.

“We are working to go even further so that American energy can be fully unleashed. Realizing the full potential of American energy means more jobs, lower prices and a more prosperous America.”

The EPA said that greenhouse gas emissions from power plants have “no material impact on global climate change”. This is despite the fact that US electricity generation is responsible for a quarter of the country’s greenhouse gas emissions. If the sector were itself a country, it would be the fifth largest carbon polluter in the world, after China, the US, India and Russia.

Trump, who has called the climate crisis “bullshit” and “a hoax”, earlier this year overturned the foundational 2009 EPA endangerment finding – spurred by a supreme court ruling – that greenhouse gases pose a significant threat to public health and the environment.

This has opened the way for the administration to scrub out any limits on the planet-heating gases that are causing our world to rapidly overheat and worsen deadly heatwaves, drought, wildfires and floods. In February, the EPA eliminated pollution standards for cars and trucks as part of a series of actions Zeldin described as “driving a dagger straight into the heart of the climate change religion”.

Environmental groups immediately vowed to challenge the latest rollback in court. “This is full-throated climate denial while the climate crisis happens in real time and a shocking betrayal of the American public,” said Holly Bender, chief program officer at the Sierra Club.

“The Sierra Club will fight back against this reckless and dangerous proposal with everything we have in the courts, in Congress, and in communities across the country.”

When it issued the latest carbon pollution standards for power plants under Joe Biden’s administration in 2024, the EPA found the rules would slash 1bn tonnes of greenhouse gases by 2047 and deliver $370bn in net benefits.

The rules also would have prevented 1,200 premature deaths and 360,000 asthma attacks in 2035 alone, due to air quality improvements. Under Trump, however, the EPA has eliminated the dollar benefit of saving lives through reduced air pollution in its calculations.

“Every American deserves to breathe clean air, but time and again this administration gives a green light to more pollution at the expense of our health,” said Gina McCarthy, who was administrator of the EPA under Barack Obama.

“Everyone will be affected by their actions, but the most vulnerable among us, our kids and grandkids, will suffer the most. Today’s decision lets the nation’s biggest industrial polluters off the hook by reversing findings the agency itself established.”

Trump has long championed the use of fossil fuels, such as coal and gas, pushing a “drill, baby drill” approach that has opened up more land for extraction while demolishing clean air and water regulations the industry said it found too onerous.

As well as handing out hundreds of millions of dollars in taxpayer funds to prop up coal plants, which have struggled economically in recent years, the Trump administration has sought to directly strangle clean energy projects such as solar and offshore wind.

The latest EPA intervention will probably be significant, if it survives legal challenge, as it will stymie any future attempt to restrict carbon pollution from power plants. It is the latest episode in a decade-long saga over how, or if, the US tames its power emissions.

In 2016 the supreme court knocked down Obama’s clean power plan. A more narrow version, with the parameters set again by the court, was then enacted under Biden.