U.S. Climate Progress Could Slow by More Than Half Under Trump

In less than a year, the Trump administration has fully transformed U.S. climate and energy policy. The changes have come through the tax code, regulatory repeals, and sweeping but fickle tariffs. Taken together, it means that the worst-case scenario for climate action under Biden has now become the best-case scenario under Trump.

That’s one of the key findings of the Rhodium Group’s latest Taking Stock report, an annual look at how U.S. policies will shape our energy system and emissions trajectory. It’s the first comprehensive assessment of the degree to which Trump’s second term, early as it is, could impede the energy transition. While total U.S. emissions are not expected to go up in the coming decade, the report projects greatly diminished progress compared to the path we were on a year ago.

That point is most clearly illustrated by the following finding: For the past two decades, the U.S. has been reducing emissions by an average of 1% per year. In the coming decade, Rhodium projects that Trump’s policies could reduce this rate by more than half.

Last year’s report, produced at the absolute peak of U.S. climate policy, modeled the effect of clean energy tax credits in the Inflation Reduction Act, new regulations on cars, trucks, power plants, and oil and gas operations, Biden’s freeze on new liquified natural gas export facilities, and a number of state-level policies. While these actions were not expected to be enough to fulfill Biden’s promise to the rest of the world under the Paris Agreement to cut emissions by 50% to 52% by 2030 compared to 2005, they represented America’s first credible show of climate leadership on the global stage. The report estimated that by 2035, we would be able to reduce greenhouse gas emissions 38% to 56%.

Now the low end of that spectrum has become overly optimistic. Rhodium has revised its estimate downwards to reflect revisions to the tax credits in the One Big Beautiful Bill Act — namely, the early end of subsidies for wind, solar, and EVs. The new report also takes into account tariffs, which primarily serve to reduce industrial activity in the U.S. in the near term, Congress’ cancellation of California’s vehicle emissions waivers, and Trump’s efforts to roll back greenhouse gas regulations. The result is that Rhodium expects emissions to decline by 26% to 35% by 2035.

The gap between this projection and last year’s represents about 800 million to 1.3 billion metric tons of carbon. On the high end, that’s roughly equivalent to the emissions from California, Texas, and Michigan combined.

The estimates are expressed as a range because the report looks at what would happen under three different scenarios. The highest emissions scenario models a world where oil and gas prices remain low, clean technology costs remain high, and the economy grows faster than current projections. The low emissions scenario is the opposite — it shows how Trump’s policies will affect our trajectory if oil and gas prices are higher, clean technologies see steeper cost declines and performance improvements, and economic growth is more aligned with current projections. The mid-emissions scenario splits the difference.

The most significant policies for shifting our emissions trajectory, according to Ben King, one of the report’s authors, are the combination of tax credits and regulations affecting the power sector. The regulations, in particular, mean the difference between having almost no coal plants on the grid by 2040 and retaining as many as 77 gigawatts of coal power by that date. “That’s still a massive decline in the amount of coal relative to what we have today,” King said, “but it is a very different-looking grid than if those regulations were to stay in place.”

Whether coal plants are replaced by clean energy or natural gas largely depends on the cost of each. Somewhat counterintuitively, the report projects less coal in the high emissions scenario because low natural gas prices mean that gas plants supplant both coal and renewables.

Even the forms of clean energy that the Trump administration supports, such as nuclear and geothermal, are not expected to play a significant role in reducing emissions over the next 15 years. For example, in the low emissions scenario, where oil and gas prices are high, about 2 gigawatts of new advanced nuclear is added to the grid in the 2030s. But because the tax credit for existing nuclear plants is set to expire in 2032, the models project that 2 gigawatts to 5 gigawatts of nuclear power will shut down in the 2030s, more than canceling out the additions.

The effect of unwinding transportation-related regulations and incentives is more straightforward — fewer EVs, higher emissions. Last year’s report projected that up to 72% of all light duty vehicle sales would be electric by 2032. The new report expects light duty EV sales to make up just 43% of the total, at most, by 2040. This is almost entirely due to the loss of greenhouse gas rules. If those remained in place, EV sales could reach 71% by 2040.

Perhaps the only bright side in the report is a section on household energy costs. The loss of tax credits for renewables and home efficiency upgrades will raise electricity bills compared to the projections in last year’s report. But despite that, Rhodium expects overall household energy costs to decrease in the coming decades — in all scenarios. That’s primarily due to the switch to electric vehicles, which lowers transportation costs for EV drivers and puts downward pressure on the cost of gasoline for everyone else.

No modeling exercise is perfect, and this one contains a number of caveats. One of the biggest points of uncertainty right now is how much energy demand from data centers will grow. The authors modeled just one pathway for data centers, with power demand nearly doubling by 2030 and more than tripling by 2040. But they note that analyst estimates fall as much as 80% higher or 80% lower. If demand turns out to be higher, “it would effectively turn up the dial on the trends that we’re seeing already,” King said.

Another area of uncertainty is that the Trump administration is working overtime to find creative new ways to stymie wind and solar development, as my colleague Jael Holzman has documented. It could turn out that these moves are even more effective than what Rhodium has captured in this report, King told me. With tariffs changing on a weekly, sometimes even daily basis, it was also difficult to capture how much of an impact they will have on technology prices, he said. Lastly, there’s a human behavior element that’s difficult for models to project.

“In the absence of government support, this is all going to happen on the basis of what private investors see as wise moves moving forward,” King said. “I don’t know the extent to which they might look at the uncertainty that the Trump administration is introducing for some of these technologies, and say, ‘Gosh, I’m going to avoid that for the foreseeable future, and maybe even beyond.’”