McCarthy Building Companies has successfully completed the 800 MWdc (593 MWac) Double Black Diamond Solar project for Swift Current Energy, marking a major milestone in U.S. renewable energy infrastructure. Located about 30 miles west of Springfield, Illinois, the new facility is now the largest operating solar energy site east of the Mississippi River, delivering significant capacity to meet the state’s growing electricity demands.

A New Era of Solar Power in the Midwest

The massive project, which began construction in late 2022, reached commercial operation in 2024 and now produces enough clean energy annually to power approximately 100,000 homes. Over the course of construction, more than 1 million safe work hours were logged, creating around 500 local jobs and offering long-term career training opportunities in the solar sector.

“We are grateful to have played a role in building the Midwest’s largest solar project,” said Jeffery Boyer, vice president of operations for McCarthy’s Renewable Energy & Storage team. “Thanks to the great partners on this project, we were able to support the area’s economy by hiring and training local trades in the growing solar construction sector, helping prepare them for long-term careers in the industry. Most of the project’s components were sourced from U.S. manufacturers, making this a great example of an American-made energy project.”

A Commitment to Domestic Manufacturing and Equity

Swift Current Energy prioritized domestic sourcing for the project, with First Solar providing most of the 1.6 million solar modules from its Ohio facility, and racking solutions supplied by Nextracker, which utilized 100% U.S.-made steel in its Chicago-area manufacturing. The project also met rigorous labor standards under Illinois’ Clean and Equitable Jobs Act (CEJA), expanding job opportunities across underserved communities.

“Electricity demand in the U.S. is accelerating with new manufacturing load and tech needs. Our Double Black Diamond Solar facility is an example of how we are utilizing U.S. manufacturers and American workers to provide the energy needed to charge our country’s growth now,” said Eric Lammers, CEO and co-founder of Swift Current. “We thank our customers in collaboration with Constellation for their commitment to this project. We especially thank Sangamon and Morgan Counties for welcoming us into their communities during development and construction. We will continue to honor our commitments as we operate Double Black Diamond.”

A Wide-Ranging Impact

The project has attracted high-profile energy users, including the City of Chicago, which now sources 70% of its municipal power—covering operations like O’Hare and Midway airports—from the facility. Other notable customers include CVS Health, Loyola University Chicago, PPG, State Farm, TransUnion, and Cook County, all of whom are receiving renewable energy from the site via Constellation NewEnergy Inc.

“Double Black Diamond Solar demonstrates what’s possible when we bring customers and clean energy solutions together. We were proud to work closely with the City of Chicago and other customers to help bring this new capacity to life,” said Kathleen Barrón, Constellation’s Executive Vice President and Chief Strategy Officer. “Efforts like this aren’t just about reducing emissions – they also drive local investment, support American manufacturing, and help communities realize the full value of clean energy while advancing their sustainability goals.”

Long-Term Community Benefits

The solar farm is expected to generate $100 million in local tax revenue over its lifetime, with more than 60% going to local public schools and the remainder funding services such as public safety, infrastructure, and community programs throughout Sangamon County. Swift Current is also contributing $10 million in community benefit funds to the Sangamon Growth Alliance, Auburn School District, City of Chicago, and Cook County.

Swift Current Energy will serve as the long-term owner and operator of the site. Tax equity for the project was provided by Google, while construction financing came from MUFG, Societe Generale, Truist, and eight additional lenders.

McCarthy’s Role in Scaling Clean Energy Nationwide

This project marks a major milestone for McCarthy’s Renewable Energy & Storage group, which has now built or is building 115+ utility-scale solar projects representing nearly 17 GW of clean energy capacity and over 9 GW of energy storage since 2010. The company continues to serve as a national EPC leader for private developers and utilities aiming to expand clean energy access across the U.S.

Originally reported by McCarthy.