Bills and Data Guides for Illinois Businesses
Understand consumption, demand, supply, delivery, and the evidence behind a useful account review.
A bill review separates the cost categories before comparing prices. Use the bill-change analyzer to reconcile two periods and see the arithmetic effect of usage, supply price, demand, and other net charges. Differences in billing days and operations need separate interpretation.
For more complex accounts, request authorized interval data and the actual account capacity values. Validate units, timestamps, coverage, meter identifiers, and gaps before relying on a model. A monthly maximum is not a substitute for a coincident-peak capacity tag.
Guides in this topic
Advanced Metering Infrastructure (AMI) for Illinois Commercial Energy
What AMI smart meters give a commercial customer, how interval data supports demand management and procurement, and how to access your data.
Updated 2026-08-01
Ancillary Services on a Commercial Electric Bill: What They Are
What ancillary services are, how they appear bundled or passed through on a commercial retail electricity bill, and why a buyer should confirm which.
Updated 2026-08-01
Capacity Tag Forecasting: How a PLC Is Set and Managed
How a commercial account's capacity tag (PLC) is set by system peak hours, why load shape drives it, and how it can be forecast and reduced.
Updated 2026-08-01
Capacity vs Transmission Pass-Through: Which to Fix in a Supply Offer
For a buyer comparing offers, how capacity and transmission differ as cost components, why a contract may fix one and pass the other through, and how to decide.
Updated 2026-08-01
Capacity, Energy, and Transmission: The Three Supply Cost Buckets
How energy, capacity, and transmission each get priced in a commercial electricity supply offer, and why a buyer should know which bucket an offer includes.
Updated 2026-08-01
Choosing a Platform for Commercial Interval Data
How to choose a tool for handling commercial interval data: ingestion, reconciliation, load-shape analysis, and authorization and privacy considerations.
Updated 2026-08-01
Coincident-Peak Alerts: Setting Up a Playbook
What coincident-peak alerts are, why the hours that set your capacity tag matter, and how to build a practical curtailment playbook around peak-alert days.
Updated 2026-08-01
ComEd Delivery vs Supply: Reading the Split on a Commercial Bill
How to separate the delivery and supply sides of a ComEd business bill, why only supply is shoppable, and how the split prevents overstating savings.
Updated 2026-08-01
ComEd's Purchased Electricity Adjustment (PEA): How It Moves Your Monthly Bill
What ComEd's PEA rider is, which customers it applies to, why it changes month to month, and why it does not touch a fixed ARES supply contract.
Updated 2026-08-01
Commercial Interval Data: Request, Validate, and Use It
A practical Illinois guide to requesting utility interval usage data, checking CSV quality, calculating load shape, and using it in energy procurement.
Updated 2026-08-01
Deconstructing a Commercial Natural Gas Bill in Illinois
The anatomy of an Illinois commercial gas bill: supply versus delivery, the purchased-gas-cost mechanism, therms, riders, taxes, and interruptible service.
Updated 2026-08-01
Demand Charges vs. Demand Ratchets: Which Applies to You
The difference between an ordinary demand charge and a demand ratchet that lets a past peak set a billing floor — and how to tell which applies to you.
Updated 2026-08-01
EV Fleet Charging and Your Capacity Tag
How uncontrolled commercial EV and fleet charging can raise peak demand and the capacity tag, and how managed charging and up-front modeling mitigate it.
Updated 2026-08-01
How Battery Storage Lowers Capacity and Transmission Costs
How behind-the-meter battery storage can reduce peak demand and lower the capacity tag and transmission cost components, with honest, site-specific caveats.
Updated 2026-08-01
How to Read a ComEd Commercial Electric Bill
A line-by-line orientation to a ComEd commercial bill: delivery vs supply, demand and capacity determinants, riders, and usage data.
Updated 2026-08-01
Interval Data Granularity: 5-min vs 15-min
What interval-data granularity means and how finer versus coarser intervals affect demand analysis, peak identification, and billing determinants.
Updated 2026-08-01
Peak Load Contribution (PLC) for Tenants in Multi-Tenant Buildings
How capacity tags work for tenants in multi-tenant buildings: submetering vs. master meter, allocation, and what a tenant can control.
Updated 2026-08-01
Peak Shaving 101: Reducing Capacity Tags in ComEd
How trimming load during PJM coincident-peak hours can lower a future capacity tag in ComEd territory, plus the practical limits.
Updated 2026-08-01
Power Factor Penalties in ComEd: Fix or Ignore?
What power factor is, when a low power factor can trigger a charge on a commercial bill, and how correction is weighed against doing nothing.
Updated 2026-08-01
Tariff Riders in ComEd to Know
What tariff riders are, how the ICC approves them, and the categories of rider a commercial customer typically sees on a ComEd delivery bill.
Updated 2026-08-01
Transmission (Network) Charges in PJM: What to Watch
How PJM transmission and network cost recovery reaches commercial bills, what drives these charges, and what buyers should watch in a contract.
Updated 2026-08-01
What Is a Capacity Tag (PLC) and How It Is Set
A plain-language guide to how a capacity tag (peak load contribution) is measured from peak-hour usage and flows into your bill.
Updated 2026-08-01
What to Do After a High PLC Year
Practical steps once a high capacity tag is locked for the delivery year: understand the set window, plan reductions, and verify the tag.
Updated 2026-08-01
Need an account-specific answer?
These guides explain how Illinois commercial energy works. A specific recommendation starts with your actual bill, usage, and contract dates.