WASHINGTON – The Biden administration on Thursday announced the first regulations to limit greenhouse pollution from existing power plants, capping an unparalleled string of climate policies that, taken together, could substantially reduce the nation’s contribution to global warming.

The proposals are designed to effectively eliminate carbon dioxide emissions from the nation’s electricity sector by 2040.

The regulations governing power plants come on the heels of other plans to cut tailpipe emissions by speeding up the transition to electric vehicles, curb methane leaks from oil and gas wells and phase down the use of a planet-warming chemical in refrigerants.

Together with the 2022 Inflation Reduction Act, which is pouring more than US$370 billion (S$492 billion) into clean energy programmes, the actions would catapult the United States to the forefront of the fight to constrain global warming.

“We are in the decisive decade for climate action, and the President’s been clear about his goals in this space, and we will meet them,” Mr Biden’s senior climate adviser Ali Zaidi said in a telephone call with reporters on Wednesday.

The government is not mandating the use of equipment to capture carbon emissions before they leave the smokestack. Rather, it is setting caps on pollution rates which power plant operators would have to meet.

They could do that by using a different technology or, in the case of gas plants, switching to a fuel source like green hydrogen, which does not emit carbon.

The nation’s 3,400 coal- and gas-fired power plants generate about 25 per cent of greenhouse gases produced by the US, pollution that is dangerously heating the planet.

The plan is sure to face opposition from the fossil fuel industry, power plant operators and their allies in Congress. It is likely to draw an immediate legal challenge from a group of Republican Attorneys-General that has already sued the Biden administration to stop other climate policies.

A future administration could also weaken the regulation.

“This proposal will further strain America’s electric grid and undermine decades of work to reliably keep the lights on across the nation,” said Mr Jim Matheson, president of the National Rural Electric Cooperative Association, which operates power plants serving the least developed communities.

Mr Patrick Morrisey, the Republican Attorney-General of West Virginia, who for the past decade has led a multi-state legal battle to constrain the Environmental Protection Agency’s (EPA) authority, predicted that the newest proposals would not survive court challenges.

“It is not going to be upheld, and it just seems designed to scare more coal-fired power plants into retirement – the goal of the Biden administration,” he added.

Senator Joe Manchin from West Virginia, a Democrat who has opposed many of his party’s climate policies, said on Wednesday that he would oppose all of Mr Biden’s nominees to the EPA unless the administration drops the regulation – a threat that carries teeth in the narrowly divided Senate.

“This administration is determined to advance its radical climate agenda and has made it clear they are hell-bent on doing everything in their power to regulate coal- and gas-fuelled power plants out of existence, no matter the cost to energy security and reliability,” said Mr Manchin, who has earned millions from his family’s coal business.

He faces a potentially difficult re-election campaign next year that could pit him against Governor Jim Justice, a Republican who has announced he will run for the Senate in 2024.

West Virginia has increasingly shifted to the right, with voters there backing Mr Donald Trump over Mr Biden by 39 points in the 2020 presidential election.

Mr Michael Regan, administrator of the EPA, announced the proposed regulations in a speech on the campus of the University of Maryland on Thursday. EPA officials chose the university setting to appeal to youth climate activists who they hope will help turn out the vote for Mr Biden’s 2024 re-election campaign.

“Every generation has its own defining challenge, one that shapes countless lives and impacts the future for decades to come, and climate change is that challenge for you,” Mr Regan told students.

“We see you, we hear you, and I am certain that President Biden does as well. That’s why when President Biden took office, he launched the most ambitious climate agenda in United States history.”

Many youth climate activists have been irate with Mr Biden after he approved an enormous oil drilling project on pristine federal land in Alaska, known as Willow. They view his actions as a betrayal of his 2020 campaign promise to halt new oil and gas drilling on public land.

The White House argues that the collective impact of Mr Biden’s climate regulations and legislation, in terms of reduced emissions, outweighs any environmental damage that would be caused by the Willow project.

Burning oil drilled at the Willow site would emit an estimated 280 million tonnes of planet-warming carbon dioxide, according to the White House. The new rules on power plants would lower emissions by 617 million tonnes between 2028 and 2042, according to the EPA.

Adding the other proposed EPA regulations would bring the total amount of eliminated emissions to 15 billion tonnes by 2055 – roughly the amount of pollution generated by the entire US economy over three years.

Several analyses have projected that the Inflation Reduction Act will cut emissions by at least another billion tonnes by 2030.

That could put the nation on track to meet Mr Biden’s pledge that the US would cut its greenhouse gases in half by 2030 and stop adding carbon dioxide to the atmosphere altogether by 2050. But analysts have said that more policies will need to be enacted to reach the latter target.

That is the action required of all major industrialised countries, scientists said, to keep average global temperatures from reaching 1.5 deg C above pre-industrial levels.

Beyond that point, the effects of catastrophic heat waves, flooding, drought, crop failure and species extinction would become significantly harder for humanity to handle.

The planet has already warmed by an average of 1.1 deg C.

“Each of these several regulations from the EPA are contributing to the whole picture that is necessary to steer this ocean liner away from the worst climate disaster,” said Mr Dallas Burtraw, an economist with Resources for the Future, a non-partisan research organisation that focuses on energy and environmental policy.

EPA officials said the proposed regulations are designed to offer flexibility to industry. For example, coal plants that are already scheduled to retire before 2032 may not have to install new pollution controls like carbon capture technology.

About a quarter of operating coal-fired power plants are already scheduled to retire by 2029, according to the Energy Information Administration.

While the proposed rules would increase costs for power plant operators, the EPA estimates that limiting pollution from smokestacks would produce a net economic benefit of up to US$85 billion by 2042 through improved public health from lower levels of soot and sulfur dioxide, which also spew from coal-fired power plants.

By 2030, the proposed standards would prevent about 1,300 premature deaths, more than 800 hospital and emergency room visits, more than 300,000 cases of asthma attacks, 38,000 school absences and 66,000 lost workdays, according to the EPA.

In some ways, the EPA move is designed to speed up changes that are already under way in the energy industry.

Coal, the dirtiest fossil fuel, is in decline – no new coal plants have been built in the US in the last decade. In the same time frame, the cost of wind and solar power has plummeted, and electricity generation from wind turbines and solar panels has more than tripled.

Wind now generates more than 10 per cent of the nation’s electricity, and solar power now accounts for about 3 per cent and is growing fast. As a result, planet-warming pollution from power plant smokestacks has dropped about 25 per cent in the last decade, absent any direct regulation.

In recent years, many large electric utilities have announced targets to stop adding carbon dioxide to the atmosphere by 2045 or 2050.

“Our emissions continue to go down as a sector, and we predict that will continue to happen regardless of the rule,” said Ms Emily Fisher, executive vice-president of clean energy and general counsel at the Edison Electric Institute, an organisation that lobbies on behalf of investor-owned electric utilities.

But some lobbyists said the timeline proposed by the Biden administration is beyond what industry can achieve.

“They didn’t just come up with those targets on the back of an envelope,” said Mr Jeffrey Holmstead, a lawyer who represents fossil fuel companies and electric utilities with the firm Bracewell LLP. “If the idea is to go significantly faster than that, then companies are going to have real concerns.”

Ms Lissa Lynch, a lawyer with the Natural Resources Defence Council, an advocacy group, said electric utilities had complained about new clean air regulations for decades but had ultimately managed to comply. “The industry always claims they are impossible to meet, cost too much money, threaten reliability and the economy,” she added of the regulations. “Ultimately they go on to innovate and comply, often well in advance of the deadlines that are set.”

Nearly a decade ago, Mr Biden’s former boss, President Barack Obama, tried to regulate emissions from power plants. His administration wrote broad and ambitious rules that were designed to replace coal-fired plants with wind farms and solar panels.

That policy was never implemented. It was first blocked by the Supreme Court and later rolled back by President Trump.

Last summer, the Supreme Court confirmed that the EPA had the authority to regulate carbon dioxide emissions from power plants, but in a limited way.

Biden administration officials involved with the new power plant rule – many of whom worked on the defunct Obama rule – have sought to ensure that this time it will stand up to scrutiny.

“In light of what the Supreme Court ruled, they’re not swinging for a home run,” said Mr Richard Lazarus, an environmental law professor at Harvard Law School. “They’re swinging for a hit.” NYTIMES