ComEd is rejecting speculative data center interconnection requests as grid pressure reaches constraints, forcing developers to prove operational viability.

ComEd, the primary electric utility for Chicago and northern Illinois, is tightening grid-connection standards in an effort to block speculative data center projects. Pressure on the grid that services roughly 70 percent of the state has intensified due to new hyperscale data center developments, and ComEd's new safeguards appear to be moderating energy demand.

In 2025, ComEd faced 75 large-load requests, including prospective data center developments, according to Crain's. Six data center projects committed $1 billion in letters of credit under a new Transmission Security Agreement to ensure their power demands won't spike residential customer bills.

Yet the regulations threaten to constrain Illinois real estate development of one of the nation's fastest-growing—and most lucrative—asset types. When ComEd evaluated 11 large-load projects, only four survived scrutiny. Since the AI boom, ComEd and other energy providers have seen an explosion of speculative data center proposals that could consume vast amounts of electricity.

ComEd proposes requiring demand-response controls during peak demand periods or mandating that data centers provide their own power. The approach appeals to many Illinois residents concerned about rising electricity bills to subsidize an industry receiving billions in tax breaks.

The data center surge has prompted political figures and municipalities across the state to recommend or implement moratoriums on development. The asset type has become a political flashpoint, with data center regulation expected to be a key issue in the upcoming Chicago mayor's race.

Suburban resistance has escalated to litigation: Chicago suburbs are suing data center companies including T5 in Grayslake, while Cicero is mobilizing to legally challenge a Digital Realty development at the neighboring Hawthorne Race Course site.