The broad safe harbors in question have to do with the way the government defines the “beginning of construction,” which, in the realm of federal tax credits, is a term of art. Under the current Treasury guidance, developers must either complete “physical work of a significant nature” on a given project or spend at least 5% of its total cost to prove they have started construction during a given year, and are therefore protected from any subsequent tax law changes.
As my colleague Matthew Zeitlin previously reported, oftentimes something as simple as placing an order for certain pieces of equipment, like transformers or solar trackers, will check the box. Still, companies can’t just buy a bunch of equipment to qualify for the tax credits and then sit on it indefinitely. Their projects must be up and operating within four years, or else they must demonstrate “continuous progress” each year to continue to qualify.
As such, under existing rules and Trump’s new law, wind and solar developers would have 12 months to claim eligibility for the investment or production tax credit, and then at least four years to build the project and connect it to the grid. While a year is a much shorter runway than the open-ended extension to the tax credits granted by the Inflation Reduction Act, it’s a much better deal than the House’s original version of the OBBBA, which would have required projects to start construction within two months and be operating by the end of 2028 to qualify.
Or so it seemed.
The tax credits became a key bargaining chip during the final negotiations on the bill. Senator Lisa Murkowski of Alaska fought to retain the 12-month runway for wind and solar, while members of the House Freedom Caucus sought to kill it. Ultimately, the latter group agreed to vote yes after winning assurances from the president that he would “deal” with the subsidies later.
Last week, as all of this was unfolding, I started to hear rumors that the Treasury guidance regarding “beginning of construction” could be a key tool at the president’s disposal to make good on his promise. Industry groups had urged Congress to codify the existing guidance in the bill, but it was ultimately left out.
When I reached out to David Burton, a partner at Norton Rose Fulbright who specializes in energy tax credits, on Thursday, he was already contemplating Trump’s options to exploit that omission.
Burton told me that Trump’s Treasury department could redefine “beginning of construction” in a number of ways, such as by removing the 5% spending safe harbor or requiring companies to get certain permits in order to demonstrate “significant” physical work. It could also shorten the four-year grace period to bring a project to completion.
But Burton was skeptical that the Treasury Department had the staff or expertise to do the work of rewriting the guidance, let alone that Trump would make this a priority. “Does Treasury really want to spend the next couple of months dealing with this?” he said. “Or would it rather deal with implementing bonus depreciation and other taxpayer-favorable rules in the One Big Beautiful Bill instead of being stuck on this tangent, which will be quite a heavy lift and take some time?”
Just days after signing the bill into law, Trump chose the tangent, directing the Treasury to produce new guidance within 45 days. “It’s going to need every one of those days to come out with thoughtful guidance that can actually be applied by taxpayers,” Burton told me when I called him back on Monday night.
The executive order cites “energy dominance, national security, economic growth, and the fiscal health of the Nation” as reasons to end subsidies for wind and solar. The climate advocacy group Evergreen Action said it would help none of these objectives. “Trump is once again abusing his power in a blatant end-run around Congress — and even his own party,” Lena Moffit, the group’s executive director said in a statement. “He’s directing the government to sabotage the very industries that are lowering utility bills, creating jobs, and securing our energy independence.”
Industry groups were still assessing the implications of the executive order, and the ones I reached out to declined to comment for this story. “Now we’re circling the wagons back up to dig into the details,” one industry representative told me, adding that it was “shocking” that Trump would “seemingly double cross Senate leadership and Thune in particular.”
As everyone waits to see what Treasury officials come up with, developers will be racing to “start construction” as defined by the current rules, Burton said. It would be “quite unusual” if the new guidance were retroactive, he added. Although given Trump’s history, he said, “I guess anything is possible.”
