Illinois · municipal utility
St. Charles Municipal Electric Utility: power factor rules
Demand-billed commercial customers with a metered power factor below 0.85 have their billing demand increased.
Power-factor rule confirmed Tariffs checked 2026-10-03
Smaller customers
Rate 3 Small General Service has no power-factor adjustment.
The power-factor rule
Rate 5 General Service; Rate 7 Large General Service (450 kW and up); Rate 9 Primary Metered Large General Service
Applies to: Demand-billed non-residential customers.
How it works: If the metered power factor in the billing cycle is below 0.85, billing demand is multiplied up by the shortfall.
Formula: Billing demand = (1 + (0.85 − PF)) × metered demand.
Example: Illustration: 500 kW metered at 0.78 PF gives (1 + 0.07) × 500 = 535 kW billing demand. At 0.85 or above, billing demand is the metered 500 kW. Illustration, not a bill estimate; billed demand, measurement intervals, minimums and credits determine the actual adjustment.
"If customer's metered power factor is below .85 in the current billing cycle, the customer billing demand will be adjusted ... Billing Demand = (1+(.85 - Power Factor)) x metered demand."
Source: City of St. Charles, IL Code of Ordinances, Title 13, Ch. 13.08 Electricity, Sections 13.08.260 B.2, 13.08.275 B.2, 13.08.292 B.2 (Power factor correction). Municode Supplement 10 (posted September 22, 2026). Checked 2026-10-03; review by 2027-10-03.
Caveats
- The latest amending ordinance for Rates 5 and 7 was not verified.
What to do next
- Size the kVAR for your load.
- Send us a bill and we'll tell you what you're paying and what correction is worth.
Cities we serve in St. Charles Municipal Electric Utility territory
Tariffs change. This summary reflects the documents cited above as checked on 2026-10-03; your utility's current rate schedule and your bill govern what you pay.