State regulators’ review of the controversial power line proposed to stretch across three rural Maryland counties will extend to at least February 2027, officials announced Thursday, a timeline that prevents developers from meeting the grid operator’s deadline to ensure reliable electricity.

Under the Public Service Commission’s new schedule, the project developer, the New Jersey-based Public Service Enterprise Group, must file environmental analyses of its route by March 2026. Over two weeks in September 2026, the commission plans to hold public hearings in counties along the project’s 67-mile path, while final briefs on the proposal aren’t due to regulators until February 12 of the next year.

That marks a significant delay to the timeline requested by PSEG, which had proposed a final decision by the end of March 2026 in order to finish construction by June 1, 2027.

The region’s grid operator, PJM Interconnection, commissioned New Jersey-based PSEG to build the Maryland Piedmont Reliability Project and has warned that growing demands from data centers and electrification could soon strain its system. The grid operator has said that if the Piedmont Reliability Project and other new transmission lines aren’t built, the region could suffer rolling brownouts and blackouts as soon as the summer of 2027.

In a statement announcing the timeline, PSC spokeswoman Tori Leonard said the commission takes the reliability of the power grid seriously.

“In adopting this schedule that includes a longer timeline than PSEG had requested, the Commission has confidence that PJM, the region’s grid operator, will efficiently maintain the grid during the duration of the Commission’s review of PSEG’s application,” Leonard said.

The Public Service Commission notes in its order that PSEG didn’t submit its permitting application until the last day of 2024, months later than the company had indicated it would file, which left regulators less time for review.

PJEM spokesman William Smith said the developer is reviewing the schedule to determine next steps.

“The MPRP is a necessary infrastructure project to ensure grid reliability and affordability for Maryland ratepayers,” Smith said.

A spokesperson for PJM did not respond to emailed questions about the consequences of the delay.

The $424 million proposed transmission line has sparked a firestorm of opposition along its route through Baltimore, Carroll and Frederick counties. That’s partly because the line would shuttle electricity from Pennsylvania to the doorstep of Northern Virginia, where energy-hungry data centers are adding new stress to the power grid.

Tensions have flared to the point that PSEG sought the assistance of U.S. marshals to complete required surveys on the land of unwilling property owners.

A federal District Court judge in Baltimore has granted surveyors permission to enter the properties of non-consenting landowners but denied the company’s request for U.S. marshal help last month after most landowners said they allow the surveys.

Project opponents welcomed the PSC’s decision this week to take more time in its review.

“PSEG came into Maryland under the cover of darkness, misleading residents, suing our neighbors, threatening homes with eminent domain, and trying to force an unnecessary project on a reckless timeline,” Baltimore County Republican Del. Nino Mangione posted on social media Thursday.

Mangione, who’s running for County Council, called the new hearing schedule “a tremendous victory” for his side.

“We applaud the PSC for rejecting PSEG’s rushed schedule, but this fight is far from over,” he said.