A revised analysis of the climate and energy costs associated with last year’s Inflation Reduction Act is projecting that one of the Biden administration’s signature initiatives will leave taxpayers on the hook for more than twice as much as initially projected, or more than $1 trillion.

The analysis by the Penn Wharton Budget Model at the University of Pennsylvania says the climate and energy provisions of the bill alone are now expected to cost $1.045 trillion over the next decade, up considerably from the $385 billion the center said the provisions would cost when the measure was first signed by President Biden last summer.

Working with economists from Goldman Sachs, the analysts at the University of Pennsylvania now project that Mr. Biden’s push to force Americans into electric vehicles will cost $393 billion over the next 10 years; that initiatives aimed at promoting investments in solar and wind projects will cost taxpayers $263 billion; and that spending to encourage the manufacturing of solar, wind, and battery components will cost $183 billion. The remaining costs of the bill are accounted for by hydrogen projects, carbon-capture initiatives, biofuels, and energy efficiency grants and loans.

After earlier failing to convince Republicans to go along with his Green New Deal, Mr. Biden managed to get many aspects of that initiative through Congress by teaming up with Senator Manchin of West Virginia and re-branding the bill as the Inflation Reduction Act in summer 2022. Mr. Manchin’s support for the bill, negotiated in secret, came to cost him dearly. His popularity at home plummeted after its passage, and he is now considered one of the most vulnerable Democrats in the Senate for the 2024 elections.

More recently, Mr. Manchin has railed against the bill he himself orchestrated, claiming that the Biden administration reneged on promises it made to invest in fossil fuel production along with the clean energy initiatives.

“If the administration does not honor what they said they would do and continue to liberalize what we are supposed to invest in over the next 10 years, I will do everything in my power to prevent that from happening,” the senator said during an appearance on Fox News Monday. “And if they don’t change, then I would vote to repeal my own bill.”

“They broke their word to the American public,” Mr. Manchin said. “This legislation was balanced. In the next 10 years, we are going to have enough fossil fuel to run our country and to help our allies around the world. We will also be investing in new technology for the future.  

“Now, the Biden administration has disregarded this completely. This was about energy security, and we have not heard a word about energy security out of their mouths since it was passed. It’s all about the environment,” he said. 

The odds of a repeal of the measure, with a Democrat in the White House and the party holding a narrow majority in the Senate, are practically nil. Mr. Biden and his fellow Democrats — most of whom consider climate change an existential threat meriting even more debt than the $30 trillion already weighing down the country — consider the bill one of the current administration’s most significant achievements.