New transmission substations in LaSalle and Woodford Counties expand capacity to enable utility scale wind farms while enhancing reliability for surrounding communities

ComEd today announced the successful energization of two new 345 kV transmission substations to its grid, enabling the interconnection of up to 550 megawatts (MW) of wind generation in LaSalle and Woodford counties.

With unprecedented demand for electricity across the US and here in Illinois, ComEd customers have seen the impact of higher PJM, the electric transmission grid operator for 65 million people in 13 states and the District of Columbia, including ComEd’s service area, capacity costs driven by a growing supply and demand imbalance, putting upward pressure on customers. To bring long term relief for customers more generation resources will be needed, and ComEd is committed to advancing grid investments that increase capacity and make way for the integration of more renewable energy generation, including from two new wind farms to be built in LaSalle and Woodford counties in the next two years. These substations clear the way for commercial operation of two future wind farms, Osagrove Flats (150 MW) and Panther Grove (400 MW), in late 2026 and early 2027, respectively.

In addition to enhancing reliability for the greater transmission network, ComEd’s newest substations are critical to enabling the interconnection of new utility scale wind farms to the grid, supporting up to 550 MW of new wind generation expected to come online in 2026-2027. This capacity is equivalent to the amount of energy needed to serve approximately 264,000 homes for a year.