Original article by Josh Gabbatiss and Ho Woo Nam republished from Carbon Brief under a CC license.

President Donald Trump’s dismantling of climate policy means the US will add an extra 7bn tonnes of emissions to the atmosphere from now until 2030, compared to meeting its former climate pledge under the Paris Agreement.

Since winning office last November, he has issued a series of executive orders and is poised to sign his “big beautiful bill” that effectively terminates Biden-era climate policies.

Carbon Brief’s analysis of modelling from the Princeton University REPEAT Project shows that this means US emissions are now set to drop to just 3% below current levels by 2030 – effectively flatlining – rather than falling 40% as required to hit the now-defunct target.

This would leave the US around 2bn tonnes short of its greenhouse-gas emissions target for that year, adding emissions equivalent to around 4% of the current global total each year

To put this in context, it is roughly the annual output of Indonesia, the world’s sixth-largest emitter.

Trump is already withdrawing his nation from its international climate obligations under the Paris Agreement.

The passage of the new Republican-backed “megabill” means that US climate targets pursued by Trump’s predecessor now appear firmly out of reach. 

7bn tonnes

Trump is due to sign the so-called “big beautiful bill” into law after it was approved by the Republican-controlled US Congress on 3 July.

This “megabill” removes virtually all of the tax credits for renewable energy, electric vehicles and clean manufacturing that were at the core of Biden’s landmark Inflation Reduction Act (IRA).

(Ahead of the US presidential election last year, Carbon Brief estimated that, by reversing the IRA and other key policies, a Trump administration would add 4bn tonnes of emissions by 2030, compared to a continued Biden administration.)

Since his return to the White House, Trump has moved to strip away his predecessor’s climate policies, including via a series of executive actions. This includes targeting vehicle fuel-efficiency standards and power sector emissions standards.

The passage of the new bill means US solar and wind power expansion will likely slow down, as will sales of electric vehicles and energy efficiency improvements. The combined effect of these policy rollbacks can be seen in the chart below, based on modelling by the REPEAT Project.

Carbon Brief has compared the impact of Trump’s policies, including the megabill, to a pathway on which the US meets its former target, under the Paris Agreement, to cut greenhouse gas emissions by 50-52% from 2005 levels by 2030. 

The cumulative gap between this pathway and the Trump administration’s trajectory amounts to 7bn tonnes of emissions over the next five years.

Based on the most recent central estimate of the “social cost of carbon” in 2030 from the US Environmental Protection Agency (EPA), published under the Biden administration, those 7bn tonnes of extra emissions would cause global climate damages worth more than $1.6tn.

Under this new set of US policies, emissions are only expected to be 20% lower than 2005 levels by 2030, rather than 50-52%, meaning the nation would be 2bn tonnes short of its goal.

This amounts to just a 3% drop from 2024 levels by 2030, meaning emissions are effectively flatlining.

Renewables down, prices up

Among the hundreds of provisions in the new Republican-backed bill are several key rollbacks that are expected to affect US emissions.

Under the IRA, wind and solar projects could receive tax credits up to 2034. Following the Republican bill, most projects would need to start construction within the next year to qualify.

Without federal support, the pipeline of new renewable-energy projects is expected to contract.

The REPEAT analysts estimate that cumulative new solar capacity additions will drop by 29 gigawatts (GW) by 2030 and around 140GW by 2035. For wind power, the decrease is set to be 43GW by 2030 and 160GW by 2035.

Some renewable projects will likely be built without support, but developers will need to contend with other Trump administration policies, such as stopping federal windfarm approvals.

The lost renewable capacity is unlikely to be entirely replaced by fossil fuels, due to a multi-year backlog in the construction of gas-fired power plants. 

Tax credits for nuclear and geothermal power have been retained until 2036 in the bill. While these projects generate clean electricity, they can also take a long time to build. 

Other key policies in the new bill include the removal of tax credits worth up to $7,500 to purchase electric vehicles, which could result in tens of millions fewer such cars and vans being sold. Ending tax credits for low-carbon manufacturing is also expected to undo progress in building clean technologies, such as solar panels and electric cars, domestically.

Beyond its effect on US emissions, various early analyses have suggested the Republican-backed bill is likely to increase energy prices and lead to job losses.

REPEAT estimates household energy costs are likely to be $165 higher in 2030 and more than $280 higher by 2035, following the passing of the bill.

Some of this increase can be attributed to fewer electric vehicles on the road, leading to higher petrol and diesel consumption and prices. Slowing construction of solar and wind projects as power demand increases will also likely affect the cost of electricity.

Without tax credits to boost the construction of new generation capacity, residential electricity prices are set to increase by 7% – or $110 – by 2026, for the average US customer, according to analysis conducted for trade body the Clean Energy Buyers Association.

In the state of Wyoming, the same analysis found that electricity prices may rise by as much as 30% over the next year. Other firmly Republican states, such as North Carolina and Tennessee, are also expected to see near-term price rises in the double digits.

Methodology

Modelling of the impact of the Trump administration’s “big beautiful bill” is from the REPEAT Project, a joint initiative of the Princeton University ZERO Lab and Evolved Energy Research. 

The project has assessed the emissions impact of the executive actions that the Trump administration has already taken to unwind Biden-era policies, as well as the bill itself. 

Carbon Brief compared this trajectory out to 2030 with a straight-line pathway towards the official US climate target for 2030. This is set out in the US’ nationally determined contribution (NDC) under the Paris Agreement. It is worth noting that the Trump administration is withdrawing the US from the Paris Agreement.

Original article by Josh Gabbatiss and Ho Woo Nam republished from Carbon Brief under a CC license.