The site of what was Pennsylvania's largest coal-fired power plant is now one of the busiest construction projects in the country. Homer City Generation said on September 4 that more than 1,800 tradespeople are working on the Homer City Energy Campus, nearly double the 1,000 it reported in March. It expects about 2,000 by the end of the year.
The project is the most ambitious attempt yet to build a gas-fired power plant expressly to serve AI data centers. It is also a test of how far such a plant can get while its air permit is still being challenged.
The plan
Homer City Redevelopment and contractor Kiewit Power Constructors unveiled the project on April 2, 2025. The former Homer City Generating Station, which began operating in 1969 and was permanently decommissioned on July 1, 2023, is being turned into a natural gas-powered data center campus of more than 3,200 acres. GE Vernova will supply seven 7HA.02 gas turbines, with first deliveries expected in 2026.
The developers said the campus would deliver up to 4.5 GW to support hyperscale data centers, and that its emissions per megawatt-hour would be 60% to 65% lower than the coal plant's. The company now puts the campus at 4.4 GW, according to Lehigh Daily. They also projected more than 10,000 direct on-site construction jobs over about five years, across the plant and the data center campus, and about 1,000 permanent direct and indirect positions. They projected an initial investment of more than $10 billion for power infrastructure and site readiness, with data center development adding billions more, and said the plant would run on gas from the Marcellus Shale.
The location is a large part of the appeal. The old station is about 50 miles east of Pittsburgh and is directly connected to both the PJM and NYISO transmission systems, the developers said. Much of the infrastructure from the coal plant, including transmission, is already in place.
"This project demonstrates the best in what investing in power can do; more affordable and reliable energy for everyone," GE Vernova chief executive Scott Strazik said at the launch.
Going vertical
Construction has moved from foundations to steel. In its "first steel" announcement, Homer City Redevelopment said the first structure to rise was the gas-insulated switchgear building, which will house the high-voltage equipment connecting the campus to the PJM grid. Heat recovery steam generator housings and turbine infrastructure come next.
That grid connection matters. The campus is designed to serve multiple large data center customers on site, but the developers have also said it will supply power to thousands of homes on the local grid. It is not a purely islanded plant like the behind-the-meter plants being built for single tenants in Ohio.
Financing has kept pace. Knighthead Capital Management, which originated the project more than eight years ago and leads its financing, has funded more than $1 billion into construction to date, the developer said, more than the coal plant earned in revenue in its last five years of operation.
"As we begin vertical construction, today's milestone sets us on schedule," said Corey Hessen, chief executive of Homer City Redevelopment. The developer reported no OSHA-recordable incidents in the first year of construction.
The September workforce update said about 95% of the craft workers are local and more than 135 are apprentices, with nine trade unions on site. "For years, our local didn't take in a single apprentice because the work simply wasn't here," said Shawn Steffee of Boilermakers Local 154. The hiring numbers come from the company and are not independently verified, Lehigh Daily noted.
The permit fight
The project's legal footing is less settled than its steel. The state Department of Environmental Protection issued air quality plan approval 32-00457A on November 18, 2025. It authorizes seven combined-cycle combustion turbines and up to ten simple-cycle aeroderivative units, according to DEP's technical review and Lehigh Daily.
The permit faces two appeals, both filed on December 18. Clean Air Council, PennFuture and the Sierra Club took it to the state Environmental Hearing Board, arguing that DEP failed to apply its own environmental justice policy and to weigh the plant's climate consequences. Separately, 13 young Pennsylvanians appealed the same day, with two more added on December 28. On March 23 the board denied Homer City Generation's motion to consolidate the cases.
"We will not stand by idly while our government greenlights a devastating and illegal toxic data center power plant," said Clean Air Council executive director Alex Bomstein. The company declined to comment on the appeal, according to The Allegheny Front, as cited by Lehigh Daily.
Building while a permit is under appeal is legal but carries risk. If the board were to send the permit back to DEP, the company could face new conditions on emissions or operations after spending billions on equipment designed around the existing approval.
Why it matters
Homer City shows the scale at which gas is being built for AI. At 4.4 GW, the plant is designed to serve several hyperscale campuses at once. Its developers argue that reusing an old coal site, with existing transmission and a grid connection to two markets, lets them move faster than a greenfield project.
The appeals show the other side. The groups challenging the permit are contesting a large new fossil plant justified by data center demand, on a site where a coal plant closed only in 2023. How the hearing board handles environmental justice and climate arguments will shape how other states permit similar projects.
What to watch
The developer has said first power is targeted for early 2028. Turbine deliveries from GE Vernova, expected to begin this year, are the next physical milestone. On the legal side, the Environmental Hearing Board's handling of the two appeals will decide whether the plant operates under its current permit. And the identity and size of the data center tenants, which will determine how much of the 4.4 GW is consumed on site and how much flows into PJM, remains the commercial question to watch.