CLIMATEWIRE | The rollbacks in clean energy incentives in Republicans’ budget planswill put the brakes on U.S. greenhouse gas emissions reductions by throttling the growth of renewables and electric vehicles, analyses from four research firms showed.
The extent of the Republican cuts is still being determined as the House takes up the Senate version of the GOP budget legislation. But early modeling by research groups shows the bill that passed Tuesday in the Senate would lift emissions of carbon dioxide by 8 to 12 percent from levels expected over the next decade if Democrats’ climate law, the Inflation Reduction Act (H.R. 5376 (117)), remained in place.
That figure is close to the 8 to 11 percent increase over the same period under the bill passed last month by House Republicans, according to figures calculated by the Rhodium Group. Those estimates don’t take into account the impacts the Trump administration’s regulatory actions would have on the carbon dioxide emissions released from power plants and tailpipes.
On supporting science journalism
If you’re enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
President Joe Biden pledged to cut greenhouse gases 61 to 66 percent below 2005 levels by 2035 — a target his administration said was needed to keep the world’s climate from careening further off track.
“These [bills] push those goals far out of reach,” said Jesse Jenkins, a Princeton University professor who runs the Rapid Energy Policy Evaluation and Analysis Toolkit that modeled the effects of the bills.
“These bills basically, substantively, dismantle the policy enacted by the previous administration and Congress,” he added “And so they push us back onto the much slower decarbonization trajectory.”
House and Senate Republicans will now meld the two iterations of their bill in hopes of meeting President Donald Trump’s July 4 deadline to enact the cornerstone of his policy agenda. It’s unclear exactly how the clean energy tax provisions will unfold: House GOP fiscal hard-liners railed against Senate tweaks that they claimed would continue showering green energy with incentives.
The U.S. is the world’s No. 2 emitter of greenhouse gases behind China and has been the largest historical contributor to climate change. Either of the Republicans’ bills would imperil global goals of limiting temperature rise to less than 2 degrees Celsius since the Industrial Revolution, the target laid out in the Paris Climate Agreement. Trump has vowed to pull the United States out of that pact for the second time.
And the legislation would all but seal the fate of more ambitious attempts to keep that temperature increase below 1.5 C, a point at which scientists warn the effects of climate change become more severe and irreversible — and which many scientists say is already out of reach.
Many of those climate impacts already are occurring in the form of fiercer hurricanes, severe heatwaves, unruly wildfires and devastating drought. Global temperatures set their second consecutive record last year – and surpassed the 1.5 C increase for the entire calendar year for the first time.
The Inflation Reduction Act was the nation’s most aggressive attempt to wrestle with the U.S.’ role in heating the planet. Biden and fellow Democrats hailed it as a bid by the U.S. to join the global competition for the emerging clean tech and vehicles sectors, an arena in which China has taken a sizable lead.
Trump has railed against efforts to battle climate change and dismissed the IRA’s clean energy incentives as the “Green New Scam,” as he urged lawmakers to eliminate those policies. The IRA had been expected to help bring U.S. greenhouse gas emissions down by 43 to 48 percent in 2035, according to Jenkins’ REPEAT modeling project.
Robbie Orvis, senior director of modeling and analysis at climate policy think tank Energy Innovation, said those reductions are quickly disappearing.
“Emissions will increase a lot,” he said. “You’ll have less clean energy deployed. And what will replace that will be a mix in the power sector of gas and coal.”
Jenkins’ REPEAT modeling projects that when combined with Trump’s plans to repeal emissions limits for power plants, vehicles and other sources, the House and the Senate bills would spike U.S. greenhouse gases 25.7 and 25.2 percent in 2035, respectively, compared with Biden-era policies.
Climate research firm Rhodium Group found the House bill would lead to “meaningfully higher greenhouse gas emissions levels”— between 500 and 730 million metric tons greater in 2035.
In a high-emissions scenario under the House bill, overall U.S. greenhouse gases would fall 4 percentage points by 2035 from 2024 levels — or 23 percent below 2005 levels — which amounts to “effectively no progress on decarbonization,” Rhodium said.
A low-emissions outcome would push U.S. emissions 39 percent below 2005 levels in 2035, still short of what climate scientists say is needed for the U.S. to do its part in keeping temperatures in check.
Other analyses confined their findings to the bills while maintaining rules that Trump has not yet formally rescinded. Think tank Center for Climate and Energy Solutions and research firm Greenline Insights said the Senate version would increase U.S. emissions 8 percent by 2035 from current trajectories.
Energy Innovation arrived at the same 8-percent bump — raising emissions by 280 million metric tons — while it found the House version boosted 2035 emissions by 310 million metric tons, or 8.9 percent. That 30 million metric ton spread is roughly the same amount of annual greenhouse gas emissions from 7 million gasoline-powered cars or the energy use of 4 million homes.
The two chambers’ bills offer starkly different sunsets for the clean energy incentives. The Senate iteration allowed solar and wind power developers to claim full credits for projects that begin construction within one year of bill enactment or are placed in service before 2028 — though beginning construction in that first year effectively creates a four-year runway to receive the credits before projects must be placed into service. The House required projects to commence construction within 60 days and begin operating before 2029.
The Senate also extended battery storage incentives and allowed developers to more easily finance projects by transferring credits. The Senate GOP stripped a new tax on solar and wind projects if their component parts are traceable to Chinese manufacturers from the final bill — Energy Innovation published its modeling Monday and therefore included that provision.
The 940-page bill would also end consumer credits for purchasing new and used electric vehicles, which automakers have said would slow production and jeopardize jobs.
While solar and wind power will continue getting built under the Senate bill, it would slow the pace and raise the cost, Orvis said. Natural gas power plants will run more often, operating at 52 percent capacity in 2035 compared with 35 percent currently.
Removing consumer incentives for electric vehicles would not significantly affect emissions because EPA tailpipe standards provided a floor for shifting the market off internal combustion engines, Orvis said. But those standards are not expected to stand — the EPA on Monday sent a proposed rule that is expected to revise that regulation to the White House Office of Management and Budget.
Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2025. E&E News provides essential news for energy and environment professionals.