With the sudden end of a long-standing federal tax credit for residential solar projects in sight, Maine’s solar installation companies are bracing for a short surge in demand followed by a long stretch of uncertainty.

The residential clean energy credit, sometimes referred to as the 25D solar credit, offers homeowners a federal tax credit worth 30% of the cost of a new solar system. Depending on the project, that credit can be worth a five-figure sum. But the federal reconciliation bill, which President Donald Trump signed at an Independence Day picnic, ends eligibility for any expenses made after Dec. 31, several years earlier than was previously planned. That’s left some companies scrambling to plan past six months from now.

“Our installation schedule is probably going to fill up pretty quickly, as people feel the urgency to take advantage of the 30% tax credit,” said Sam Zuckerman, owner of Brunswick-based Maine Solar Solutions. “We do have a plan in place to be able to increase our install capacity from now until the end of the year.”

That plan includes hiring a small number of temporary employees and offering 6-day workweeks to current workers interested in taking on overtime, Zuckerman said. But he expects demand to slow in the coming year.

“If it’s significant … it may impact our business operations to the point where we may need to downsize a little bit,” Zuckerman said, echoing concerns he outlined weeks ago. At that point, lawmakers were considering requiring projects to be placed into service by the end of the year to qualify, but the final version of the bill offers slightly more time.

South Portland-based ReVision Energy has also seen a recent spike in interest from both residential and commercial customers, said senior counsel Steve Hinchman.

“ReVision Energy usually fills the annual queue by fall, but this year we expect to be fully booked by midsummer. … The uncertainty is pushing timelines up across the board,” Hinchman said in a written statement. “We anticipate being quite busy through the end of 2025, but our concern is what happens after.”

Asked whether the company was considering staffing changes, a ReVision spokesperson declined to comment beyond Hinchman’s statement.

Andrea LaPlante, chief financial officer at LaPlante Home Services, said her customers are “still in the information-gathering phase” when it comes to planning around the new credit timelines, but she has already seen demand rise with the temperatures this summer.

“If the solar demand does reduce, that would be disappointing for us,” LaPlante said. But “we don’t anticipate layoffs.”

LaPlante’s company offers a range of services, including installing heat pumps and generators, so workers specializing in solar could shift to another team if demand fell too low — and vice-versa if there’s a short-term spike in solar installations, she said. But the company will likely need to shift its marketing approach to highlight the long-term savings on electricity that solar panels can provide, rather than the immediate cost savings the credits present, she said.

“That’s unfortunately going to have to be the direction that we take in our marketing,” she said. “Our customers are always interested in making sure they can take advantage of that federal tax credit.”