The Trump administration’s new clean energy tax guidance deals a fresh blow to many wind and solar companies already reeling from enactment of the Republican megalaw, raising new questions about the trajectory of renewables.

The Treasury Department plan, released Friday and mandated by an executive order on July 7, rewrites decades-old standards for how wind and solar projects can qualify for lucrative credits. The revisions no longer allow projects that incur 5 percent of their costs to be considered under construction — a move that could make it difficult for many developers to receive federal support and move forward. The guidance also requires companies to meet the new standards within two weeks, angering industry advocates.

The move “is part of an unprecedented side deal the administration made with anti-clean energy ideologues to undermine Congress,” said Abigail Ross Hopper, president and CEO of the Solar Energy Industries Association. She predicted the guidance would threaten thousands of small businesses.

States need to take “urgent action” to counteract the Trump administration, said Heather O’Neill, president and CEO of Advanced Energy United, a trade group.

“With energy demands set to soar and jobs at risk, states across the country should take executive action to speed up project procurement, siting, and permitting approvals while longer-term reforms are made,” she said.

Lawsuits, costs and a solar rally

Treasury’s guidance is part of a wider effort by the Trump administration to eliminate climate regulations and cut incentives for wind and solar.

The Interior Department has proposed new restrictions on renewable projects planned on federal land. EPA has proposed rolling back regulations on climate pollution from cars and power plants, as well as undoing the scientific finding that underpins the agency’s legal obligation to regulate carbon dioxide.

The plan also could be challenging for small solar projects that are larger than 1.5 megawatts, according to analysts.