But such logic may not prevail, MIT’s Wolfram said. ​“If we’re building a lot of battery factories and solar plants in red congressional districts, hopefully that will insulate IRA from repeal,” she said. ​“But I fear there’s a risk that Republicans would want to destroy Biden’s signature climate achievement, even if it’s against their economic interests.”

The GOP could also decide it would rather steer money earmarked to clean energy to other priorities — like tax cuts.

Wolfram co-authored a recent paper that suggested Republicans might seek to get rid of tax credits and other federal climate spending in an attempt to reduce the federal deficit because the deficit would be expected to balloon if they extend the tax cuts enacted by Congress during the first Trump administration, which are set to expire at the end of 2025.

What can Trump do on his own? 

While Congress would need to take action to fully repeal the Inflation Reduction Act, a Trump administration can make moves on its own to halt or at least complicate the provision of the IRA’s tax credits, Godfrey said, such as instructing the Treasury Department to amend, suspend, or delay implementation of the rules that determine how tax credits are calculated and disbursed.

“There is space for an administration that wants to throw sand in the gears to come in and say, ​‘We’re suspending the rule, or we’re suspending the notice of proposed rulemaking,’” Godfrey said. ​“People should be concerned about a Trump administration without complete control of Congress to use administrative powers to readjust those rules in a way that will be detrimental to their implementation.”

Beyond obstructing the Inflation Reduction Act rollout, other decisions fall squarely within the authority of the executive branch — and a future Trump administration has a blueprint to follow on those fronts.

Project 2025, the policy platform created by right-wing think tank the Heritage Foundation, calls for restructuring federal agencies — including the Environmental Protection Agency, the Department of Energy, and the Department of Interior — in ways that would restrict or end their roles in promoting clean energy and reducing greenhouse gas emissions.

Trump has disavowed any knowledge of or support for Project 2025, but CNN has reported that at least 140 people who worked in the Trump administration were involved in the project, including six of his former Cabinet secretaries.

Among the proposals in Project 2025: reversing a landmark 2009 finding from the EPA that carbon dioxide emissions are a threat to human health, which is currently the basis for federal regulations on greenhouse gases. The platform also calls for EPA to reconsider rules limiting tailpipe emissions from road vehicles and withdraw California’s long-held option to set its own vehicle standards — an ability that has allowed it and more than a dozen other states to adopt more stringent emissions rules for cars, trucks, and buses than the federal government.

Project 2025 would also have the Interior Department prioritize fossil-fuel extraction on federal lands and have the Federal Energy Regulatory Commission end consideration of environmental impacts of new fossil-gas pipelines. And the blueprint calls for key programs within the Department of Energy to be ​“eliminated or reformed,” including the Office of Clean Energy Demonstrations, Office of State and Community Energy Programs, Grid Deployment Office, and the ARPA-E advanced energy R&D program.

The $400 billion pool of loan authority under the DOE’s Loan Programs Office is also under threat. That program has already made tens of billions of dollars available to solar projects, battery factories, nuclear power plants, clean hydrogen production sites, critical-minerals mining, processing, and recycling, and a host of other climate-related projects. Project 2025 calls for eliminating the office, which under former President Obama gave crucial early loans to Tesla. News reports indicate some prospective Trump administration officials want to redirect the loan program toward fossil fuel projects instead.

A full-scale implementation of the Project 2025 agenda would harm not just U.S. clean energy and climate-related investments and economic growth, but also broader job growth and energy costs, according to an August report from think tank Energy Innovation. The analysis found that the policies called for in the blueprint would result in $320 billion in annual GDP losses, 1.7 million clean energy jobs lost, $32 billion in higher household energy costs, and an increase in greenhouse gas emissions of roughly 1 billion metric tons by 2030 compared to a scenario in which current policies were kept in place.

Godfrey expressed hope that a Trump administration would forgo the more drastic parts of Project 2025, such as eliminating ​“whole arms of DOE” that support industries such as critical-minerals mining, processing, and recycling, which are seen as crucial to U.S. competitiveness against China.

Yet he also warned that companies that have won promises of loans and grants from agencies under the Biden administration but haven’t yet received them could face the threat of clawback. ​“If you have an executed agreement in place, you should be OK. Anything short of that, I think there’s some risk there,” he said.

All of these threats run the risk not only of delaying urgent action on climate change, but of causing economic hardship in a world in which carbon-free energy is clearly beating fossil fuels on purely economic terms, said Tom Steyer, the billionaire founder of Farallon Capital Management who has backed a variety of climatetech investments and political and philanthropic causes.

“The only political party on the globe that still is denying that climate change has an impact economically and environmentally is the Republican Party,” Steyer told Canary Media earlier this year. ​“The cost of wind and solar and batteries is going to drop precipitously. The advantage they have in cost is only going to get bigger.”

“For the U.S. to try to give up the future and go back to the 1950s — an internal-combustion-engine, fossil-fuel-driven world — it destroys jobs in the United States, destroys industries in the United States, and drives up inflation,” he said.

Gina McCarthy, former national climate advisor in the Biden administration and head of the EPA under the Obama administration, was defiant in a statement Wednesday morning.

“No matter what Trump may say, the shift to clean energy is unstoppable and our country is not turning back,” McCarthy wrote. ​“Our coalition is bigger, more bipartisan, better organized, and fully prepared to deliver climate solutions, boost local economies, and drive climate ambition. We cannot and will not let Trump stand in the way of giving our kids and grandkids the freedom to grow up in safer and healthier communities.”