
US utility Commonwealth Edison (ComEd) has announced a plan to expand a 765 kV substation to add 2.45GW of renewables in Illinois.
After completion, the substation will enable five renewables projects, with a combined wind capacity of 2GW and solar capacity of 450MW, to connect to the Illinois electric grid and the PJM energy market. While the five renewables projects all include wind, two, the Heritage Prairie and Osagrove Flats projects, will include solar as well as wind generation capacity, with 300MW and 150MW of PV respectively.
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Design engineering began in September, including installing new circuit breakers, transformers, relay switches, network data, and control systems. The expansion of the project is expected to be completed in late 2026.
“The Wilton Center substation has been providing energy to our state and many others for over half a century, and with this expansion it will expand that capacity with fossil fuel-free power that will propel our grid into the future,” said JB Pritzker, governor of Illinois.
Currently, the Wilton Center substation yard is about one million square feet. It will expand by about 50% when construction is complete.
Currently, Illinois boasts a combined installed solar capacity of 2.2GW with more than 64,000 solar installation projects. While energy transition in the US is underway including Illinois, a total of three trade associations in the US have established Solar Powers Illinois to promote the benefits of solar in the state.
Solar Powers Illinois is composed of the Illinois Solar Energy and Storage Association (ISEA), the Solar Energy Industries Association (SEIA), and Coalition for Community Solar Access (CCSA). The partnership also aims to educate the people in Illinois on the value of solar energy and the opportunities and benefits that solar energy provides.