A construction schedule is a promise, and at Horseshoe Lake the crews kept theirs half a year early.
What happened
Sean Wolfe reported for Power Engineering on September 11 that OG&E has finished testing Unit 11 at its Horseshoe Lake Power Plant near Harrah, Oklahoma, six months ahead of schedule and under budget. Jerry Bohnen at Oklahoma Energy Today and Cassidy Mudd at News 9 in Oklahoma City carried the same milestone from the state side.
Unit 11 passed its performance tests on August 30 and spent the back half of the Oklahoma summer running while it was still officially in testing. It is expected to enter commercial operation in October, with Unit 12 right behind it. Together, the two units come to roughly 448 megawatts, which OG&E figures at about 300,000 homes. They replace Units 6 and 7, two machines that had been turning at Horseshoe Lake for 60 years.
The new units are GE Vernova 7FA.05 gas turbines, built to burn hydrogen as well as natural gas if hydrogen ever arrives in volume on that part of the system. The Oklahoma Corporation Commission approved the replacement unanimously in 2023. Ground broke in October 2024. That is a two-year build on a utility scale plant, and it landed early.
Why it counts
Almost none of this happened at a desk.
The turbines and generators came in by rail and then had to travel 44 miles across Oklahoma County to the plant site. Each turbine weighed 444,000 pounds. Each generator weighed 492,000 pounds and rode on a trailer carrying 240 tires. The transformers ran to roughly half a million pounds apiece. Before any of it moved, engineers at the Oklahoma Department of Transportation worked the route bridge by bridge.
"We've confirmed that all bridges along the route can support the load," Dan Knickmeyer of ODOT's Bridge Division said when the hauls began in the summer of 2025.
Behind that one sentence sit heavy haul drivers, escort crews, bridge engineers, riggers, millwrights, pipefitters, electricians, instrument and control technicians, and the plant operators who have to run the machine once everyone else goes home. Chris Lelak, OG&E's director of major projects, credited the delivery to "detailed route analyses." Schedules do not beat themselves.
"Completing Unit 11 ahead of schedule and under budget reflects our team's commitment to safety, operational execution and dedication to our customers."
Sean Trauschke, chairman, president and CEO, OG&E
Early and under budget is also an affordability story, and a quieter one than most. Every month a plant sits unfinished is a month of carrying costs on a project customers eventually pay for. Six months off a two year schedule is real money that never enters the calculation.
The numbers
The capacity: About 448 megawatts across Units 11 and 12, enough for roughly 300,000 homes, per OG&E and Power Engineering's September 11 report.
The budget: OG&E first estimated the project at up to $375 million and later raised the approved ceiling to more than $506 million, according to Oklahoma Energy Today. The company says Unit 11 came in under that budget. OG&E put the direct economic impact of the build at $536 million in its own June 2025 project announcement.
The equipment: Two 444,000 pound turbines, two 492,000 pound generators, transformers near half a million pounds each, moved 44 miles by road after arriving by rail.
The service territory: OG&E serves about 910,000 residential, commercial and industrial customers across 30,000 square miles of Oklahoma and western Arkansas.
The demand behind it: Commercial and industrial electricity use in the West South Central region is expected to rise 20 percent between the summer of 2025 and the summer of 2027, according to Energy Information Administration figures cited in the Power Engineering report.
Every figure above traces to the company's own filings and announcements or to the reporting linked at the bottom. None of them are estimates we built.
What comes next
Unit 12 is expected in commercial operation in October alongside Unit 11, with a ceremonial ribbon cutting at the site in November. The Oklahoma Corporation Commission has already pre-approved Units 13 and 14 at Horseshoe Lake, which means the site has headroom and the regulatory path for the next phase is partly cleared. Whether that phase gets built is a commission decision, made in Oklahoma City on the record, with the demand numbers in front of it.
That decision is worth watching for anyone in the trades. A pre-approved unit at an existing site with existing interconnection is about the fastest thing a utility can build, and it puts crews back on a job they have already learned. The workforce that just finished Units 11 and 12 knows the site, knows the routes, knows the bridge loads. Keeping that crew together and working is its own kind of infrastructure.
The wider point is that Oklahoma is adding firm capacity into a region where industrial demand is climbing 20 percent in two just years. Horseshoe Lake is not a speculative build chasing a customer that may not show. It is a replacement of two 60 year old units with modern machines at a site that already has the wires, the water and the workforce.
The Bottom Line
Reliability is not an abstraction. It is 448 megawatts that will be there in January, put in place by people who moved half million pound transformers down Oklahoma county roads and then finished six months early. The Oklahoma Corporation Commission approved the project in 2023, OG&E built it, and Oklahoma customers get modern capacity at an existing site without a new footprint or a new fight. That is what the buildout looks like when it works, and it is worth saying so out loud.
Sources: Sean Wolfe, Power Engineering, September 11, 2026 | Jerry Bohnen, Oklahoma Energy Today, September 11, 2026 | Cassidy Mudd, News 9 Oklahoma City, September 10, 2026 | OG&E, "Massive new generation units arrive at OG&E's Horseshoe Lake Power Plant," June 20, 2025
Positive Current
