Do Data Centers Raise Electricity Bills?

Your ComEd bill doesn't come from one company making one decision. Bartlett sits inside ComEd's service territory, and ComEd's territory sits inside the PJM Interconnection grid — a wholesale market covering more than 67 million people across 13 states and Washington, D.C. Each year, PJM holds a capacity auction: it pays power plants to promise they'll be ready to run a few years from now. That promise is called capacity, and its price flows into the supply portion of your bill.

When data centers started requesting enormous blocks of future power — Northern Virginia's "Data Center Alley" is the extreme case, but Illinois is one of the fastest-growing markets — PJM had to buy far more capacity than before. Watch what happened to the auction price:

That's more than a tenfold increase in a few auction cycles, and the last two auctions cleared at the maximum price federal regulators allow. PJM's independent market monitor, Monitoring Analytics, estimated that data centers were responsible for about 63% of the 2025/2026 price increase — roughly $9.3 billion in added cost recovered from customers. In the December 2025 auction, data centers accounted for about 40% of the $16.4 billion total, and about $6.2 billion of that was for facilities not yet built — forecasted load that may or may not materialize, but which ratepayers cover regardless.

One advocacy estimate (from the Natural Resources Defense Council) projects average PJM household bills could run roughly $70 a month higher by 2028 than before the surge, if the trajectory holds. Treat that as a projection, not a bill you'll see next month — but it shows the direction.

ComEd's public position is that large-load customers should pay their own way. In January 2026, the utility signed Transmission Security Agreements with eight large-load customers, locking in commitments for more than 6.5 gigawatts of forecasted new load — roughly the output of six nuclear reactors. The take-or-pay structure obligates those customers to pay for up to ten years of transmission service. ComEd says the agreements prevent more than $2 billion in transmission charges from being passed to existing customers over the next decade.

ComEd CEO Gil Quiniones described the agreements as "a model for how utilities and large-load developers can responsibly meet growing power requests, ensuring that customers who impose very large demands pay their fair share." ComEd had previously asked Illinois regulators for tariff changes including higher deposits from data centers — aimed at "phantom" projects that request huge power allocations and never build, leaving everyone else to cover the planning costs.

The honest caveat: these agreements cover transmission costs for new large loads. The wholesale capacity costs described above are a separate charge, set by PJM's auctions — and those are already in your supply price.

A ComEd bill has two big pieces: supply (the electricity itself) and delivery (getting it to your house). The data-center effect lives mostly in the supply piece. ComEd's "price to compare" — the supply rate you'd measure alternative suppliers against — is 10.103 cents per kWh for October 2026 through May 2027, per the Citizens Utility Board. That's about 3% lower than this past summer's price, but still roughly 53% higher than two years ago.

One cushion: Illinois' Climate and Equitable Jobs Act puts a line item on ComEd bills called the Carbon Free Energy Resource Adjustment, which flips into a credit when energy prices run high. Recently it's ranged from about 1.6 cents per kWh down to about 0.115 cents per kWh — real money off the supply charge. That benefit is scheduled to end in June 2027.

CUB has urged ComEd to work with customers struggling to afford bills and called on the Illinois legislature to pass reforms protecting customers from data-center-driven costs — so this fight is still live in Springfield.

If data centers raise bills, why does Illinois court them? Because the state decided the trade is worth it. A 2019 law offers qualifying data-center projects a sales-tax exemption on equipment for companies investing at least $250 million and creating 20+ full-time jobs, plus a 20% income-tax credit on wages for facilities in underserved areas. A Mangum Economics study found the incentives helped attract 13 projects and more than $4.2 billion in investment, creating 8,000+ construction jobs.

The facilities landing near Bartlett — in Elk Grove Village, Wood Dale, Aurora, and Chicago — are part of that wave. Our guide to data centers near Bartlett lists the verified nearby facilities. The state's bet: the jobs, tax base, and tech investment outweigh the upward pressure on power prices. Whether that bet pays off for your household specifically is the open question.

• Compare your supply rate. If you buy from an alternative supplier (or Bartlett's municipal aggregation), compare its rate against ComEd's current price to compare: 10.103¢/kWh through May 2027. CUB publishes the comparison.
• Consider budget billing. ComEd averages payments over 12 months, which smooths the seasonal spikes — it doesn't lower the total, but it ends the surprise bills.
• Know the assistance programs. The Village of Bartlett's own site points residents to ComEd for outage and billing help; ComEd offers LIHEAP-linked bill assistance, flexible payment arrangements (up to 18 installments, 24 for limited-income households), and CARE grants.
• Cut usage where it counts. Supply charges are per-kWh, so efficiency upgrades (LEDs, smart thermostats, sealing air leaks) reduce the portion of the bill data centers inflated.
• Watch Springfield. The lasting fix — making large-load customers cover their full grid costs — is a legislative fight. CUB's position is that state reforms are still needed.