37% Growth in ComEd C&I Customers? That Didn’t Pass the Smell Test.

By Nate Richards, Enerex

I was reading a summary of the Illinois Commerce Commission’s 2026 Office of Retail Market Development report in a MagniFYI featured article by David Givens when one number stopped me.

37% year-over-year growth in ComEd C&I customers on competitive supply?

That didn’t pass the smell test. Specifically, the report showed a 36.7% increase in competitively served nonresidential customers and a 21.7% increase in their electricity usage. If that much growth had occurred, I wanted to understand where it came from.

So I opened DataHub Market Share Nowcast.

The numbers were already in DataHub

We’ve developed a comprehensive market size and supplier market share tool within Enerex DataHub. For this comparison, it gave me a consistent view of the Illinois utility switching data.

The Illinois switching data in DataHub did not show that jump. The discrepancy was immediately apparent. We went back to the ICC’s own monthly workbooks to reconcile the figures, and the apparent growth disappeared.

The Excel range behind the headline

The published comparison used a partial ComEd nonresidential total for May 2025 and the full nonresidential total for May 2026.

In the ICC’s 2025 ComEd workbook, on the 05 MAY 2025 sheet, summing H11:L11 gives 116,197 competitive customers. That is exactly the 2025 baseline printed in the ORMD report. But the full nonresidential total in P11 is 159,466.

The narrower SUM range leaves out Watt Hour, High Voltage, Railroad, and Lighting/Other. Those four categories account for 43,269 customers that already existed in May 2025.

The 2026 workbook reports 158,856 competitive nonresidential customers in P10 on its May sheet. Compare that full total with the partial 2025 baseline and you get the reported growth. Compare full totals in both years and you get a slight decline:

Published comparison: 158,856 / 116,197 - 1 = +36.7%
Same classes both years: 158,856 / 159,466 - 1 = -0.38%

The published result is exactly what you get when an Excel SUM range misses four categories. We can reproduce the range mismatch from the public data; we have not inspected ICC’s internal report-building workbook.

The same omission affects electricity usage. The report’s 2025 value matches SUM(H21:L21), leaving out 671,847,281 kWh from those four categories. On a consistent basis, ComEd nonresidential competitive usage declined 1.66%, rather than growing 21.7%.

A different picture of the market

The error also changes the combined ComEd and Ameren headline:

Published figures: ORMD 2026 report, Table 1, printed page 6. Corrected figures reconcile to the ICC monthly switching filings. Combined figures cover ComEd and Ameren.

These are May-to-May comparisons: customer counts for those months and one month of electricity usage in each year. They are not annual energy totals.

That distinction matters when you are sizing a market. Finding additional supplier volume in a disclosure does not automatically mean the total market grew. It may simply explain more of the load already inside the market total.

Then I asked our AI to rewrite the market analysis

Once we had reconciled the numbers, I asked our AI to rewrite the retail market portion of the report using the correct data from DataHub Market Share Nowcast.

The assignment was specific: use consistent customer classes, distinguish customer counts from electricity usage, avoid treating May usage as annual energy, and tie the figures back to their sources. We checked the calculations and reviewed the resulting narrative against the published data.

The result is the Enerex DataHub Power Market Brief: Illinois 2026, our independent correction and market analysis. It includes the residential and nonresidential comparisons and the reconciliation showing exactly which categories explain the apparent gain.

This is why we built DataHub. Suppliers need to know how large an opportunity really is and where they stand. Brokers need market information they can explain to customers. A number becomes much more useful when you can check what it includes and follow it back to the source.

Explore DataHub to learn more about the market intelligence behind the brief.

P.S. I have notified the ICC via memo about this error. I’m confident they will re-issue the report with a correction soon.