Illinois utility tests bidirectional charging with electric school buses
ComEd, an Illinois utility, has launched a pilot program using electric school buses for bidirectional charging to stabilize the power grid. The initiative allows buses to return energy to the grid during peak demand periods. This marks an innovative step in integrating electric vehicles into grid infrastructure.
In October 2025, ComEd, the largest electric utility in Illinois, began testing bidirectional charging technology with a fleet of electric school buses in the Chicago area. The program, part of a broader effort to enhance grid reliability, enables the buses to not only draw power for charging but also discharge stored energy back to the grid when needed, such as during evening peak hours.
The pilot involves five electric school buses operated by a local school district. According to ComEd's announcement, the buses are equipped with vehicle-to-grid (V2G) capable chargers installed at the district's depot. 'This project demonstrates how electric school buses can serve as mobile energy storage units, helping to balance supply and demand on our grid,' said a ComEd spokesperson in a statement. The utility aims to reduce strain on the grid and lower costs for ratepayers by leveraging the buses' batteries, which have a combined capacity of over 1,000 kWh.
Background context reveals that Illinois has been aggressively adopting electric vehicles through state incentives, including grants for school bus electrification. ComEd's initiative builds on federal funding from the Bipartisan Infrastructure Law, which allocated resources for clean transportation projects. The buses, manufactured by a major EV producer, were delivered earlier in 2025 and have been in service for routine student transport.
Early results from the pilot, shared in the utility's report, show the buses successfully discharged 200 kWh of energy during a test peak period, equivalent to powering about 15 average homes for an hour. No issues with battery degradation or vehicle performance were reported. However, challenges include coordinating charging schedules around school hours and ensuring cybersecurity for the V2G systems.
Experts view this as a scalable model. 'Bidirectional charging with school buses could transform utilities' approach to peak management, especially in regions with high EV adoption,' noted an energy analyst from a think tank. ComEd plans to expand the program if the pilot succeeds, potentially involving more districts by 2026. This effort aligns with national trends, where similar V2G trials are underway in California and Europe, though Illinois's focus on public transit vehicles sets it apart.