An upcoming decision from the Treasury Department has clean energy boosters and industry allies preparing for a potential disruption in the nation’s electricity supply.

Just days after signing the One Big Beautiful Bill Act on July 4, President Donald Trump announced an executive order to end “market distorting subsidies for unreliable, foreign controlled energy sources.”

The order says wind and solar energy crowds out “affordable, reliable, dispatchable domestic energy sources, compromises our electric grid, and denigrates the beauty of our Nation’s natural landscape.” It calls on Treasury Secretary Scott Bessent to issue new guidance to restrict the “use of broad safe harbors unless a substantial portion of a subject facility has been built.”

The guidance, which is expected as soon as Monday, is sparking a lobbying rush from a range of concerned stakeholders, including Republicans on Capitol Hill, utilities, data center developers and major Wall Street firms that want to underwrite big, new infrastructure investments.

Those groups are worried that the new Treasury guidance will make it more challenging to qualify for tax credits based on a “beginning of construction” metric that has been practiced for years. Under current rules, projects qualify for credits if developers start on-site physical work or purchase equipment that is at least 5 percent of the total price tag of the project.

Joey Paolino, a senior policy principal with Advanced Energy United, said the clean energy group is working to spread the message that if stringent new rules are put in place, power is going to get more expensive and states could lose economic investment.

“When you cut off supply, and it seems like the guidance is moving in that direction for wind and solar, the effect is that prices will go up,” Paolino said.

The looming Treasury guidance is just part of a full-court Trump administration press to boost fossil fuels and disrupt renewable energy. Last week, EPA canceled $7 billion in solar grants, just after proposing to scrap the legal foundation for regulation of greenhouse gases as pollutants. The Department of Interior is also complicating wind and solar projects with strict new permitting rules.

The lobbying push is also coming from Senate Republicans who negotiated the OBBB. Sens. Chuck Grassley of Iowa and John Curtis of Utah are holding up confirmation processes for Treasury Department nominees. The executive order has also rankled Sen. Lisa Murkowski (R-Alaska) and other Republicans. That Senate pressure is getting its own blowback from House Freedom Caucus members like Rep. Chip Roy (R-Texas).

Some tax lawyers say that a Treasury move to substantially change how projects qualify for tax credits could be legally vulnerable in court.

The uncertainty has left some in the clean energy industry looking to the state level for more opportunities. United's Paolino said the group is communicating with governors of both parties to share strategies for how they can grow clean energy in their states.

“You can’t just replace the tax credits, there’s not going to be a one-for-one swap with HR1,” Paolino said. “But we can get creative on technology on the supply side or policies on the demand side that can expand clean energy and help keep homeowners’ rates down.”