The short answer
Use utility-provided interval data to understand when energy is consumed. Cumulative kWh, interval kWh and kW demand are not interchangeable.
The decision this guide helps you make
Check the interval length and units before calculating peaks. For example, dividing interval kWh by interval hours gives average kW for that interval.
Evidence to gather before deciding
Download data through the utility's secure account and keep timestamps, time zone, interval length and estimated/missing readings visible.
The detail that is easy to miss
A raw meter display may show multiple registers. Use the utility's explanations rather than treating every number on the screen as the monthly billable total.
Check interval units before summing
Decision case · figures, where used, are hypothetical
A hypothetical 15-minute interval averaging 8 kW represents 2 kWh. Some files already report interval kWh; converting those again creates error. Verify timestamps, interval length and daylight-saving handling.
What would make this decision ready?
Match the billing period and identify missing or estimated intervals. Keep measured peak separate from billed demand. A timestamp does not itself identify which machine caused the peak.
Understand energy versus power
A 10 kW load running for two hours uses 20 kWh. That does not mean its contribution to billed demand is always 10 kW: meters average power over defined intervals, equipment may overlap, and the tariff may apply other tests. Keep the interval length, billing period and units beside the data. A monthly kWh total describes energy consumption but cannot reconstruct the peak on its own.
Find what actually sets billed demand
Request the tariff definition and compare billed kW with the measured peak. A ratchet can use a prior peak; a contract minimum can create a floor. Capacity obligations in supply contracts may depend on different periods from local utility demand charges. Ask which component an operating change can affect and when. Avoid adding projected demand and capacity savings together unless the evidence supports both independently.
Test changes safely
Use interval data to identify simultaneous loads, then evaluate staggered starts, charging controls and schedules with the people responsible for the site. Protect refrigeration, ventilation, medical loads, production quality and comfort. A measured reduction is useful only if it is repeatable and does not shift a larger cost elsewhere. Keep a change log and compare equivalent operating periods; a quiet month after a production shutdown is not proof of a controls project’s benefit.
A demand-charge example
Illustrative billing inputs: a current billed demand of 100 kW, proposed billed demand of 85 kW and a rate of $12 per kW. The modeled demand-charge difference is $180 for that month. If a ratchet keeps billed demand at 100 kW, that immediate difference would be zero even if a measured peak falls. The calculator therefore asks for billed demand, with exclusions stated next to the output. It does not certify engineering performance or annual savings.
| Record | Why it matters | How to verify |
|---|---|---|
| Account and scope | Keeps the decision tied to the right service and customer. | Use the current utility, meter and customer class; keep account identifiers private. |
| Period and units | Prevents comparisons across different months or measures. | Write down billing days and whether the amount is kWh, kW, therms or dollars. |
| Written terms | Distinguishes a claim from an obligation. | Save the full proposed agreement, tariff or program notice and its date. |
| Unknowns and exclusions | Shows what the estimate cannot establish. | List unresolved charges, eligibility and operating assumptions before deciding. |
Use a tool without sending your numbers
A calculator is useful for checking an assumption, not for confirming a tariff, incentive or legal interpretation. Enter only nonidentifying figures in the relevant worksheet. If you need a human review, describe the question and utility first; do not paste an account number or confidential document into the inquiry. Keep the model alongside the written terms so an apparently precise output is not mistaken for a complete quote.
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Sources & further checks
Primary references checked for this guide on October 15, 2026. Follow the source for current tariffs, eligibility and program terms; rates here are not live offers.