NorthWestern Energy (Montana)

Average revenue per kWhRevenue divided by electricity sold. This average is not a tariff or a household bill.Definition ↗ is realized revenue ÷ sales, not a tariff.

MT · commercial

MT · industrial

MT · residential

Sold to retail customers in the stated state (utility x state grain); bundled full-service rows only in the summaries; energy-only and delivery-only rows are listed but never added to bundled sales. Realized average revenue per kWh is not a tariff.

SAIDISystem Average Interruption Duration Index: the minutes of sustained interruption the average customer had over the year, customer-minutes interrupted divided by customers served. Each utility calculates and reports its own figure on EIA-861 Schedule 3, under the method it declares. A system average says nothing about one address.Definition ↗, SAIFISystem Average Interruption Frequency Index: how many sustained interruptions the average customer had over the year, customers interrupted divided by customers served, as the utility reports it on EIA-861 Schedule 3.Definition ↗ and CAIDICustomer Average Interruption Duration Index: minutes per sustained interruption, SAIDI divided by SAIFI on the same basis. EIA-861 asks utilities for SAIDI and SAIFI only; EIA publishes CAIDI with the data and the atlas shows it as published, never recomputed.Definition ↗ count sustained interruptions. Figures with and without major event daysDays a utility sets apart from normal operation: EIA describes them as events such as snowstorms, floods or heatwaves, or periods of outages that differ greatly from the utility's own five-year history. EIA-861 asks for the indices both with and without them. Part B respondents determine them under IEEE 1366; Part C respondents define a major event themselves. The two series answer different questions and are never blended.Definition ↗ are different measures; compare like with like.

MT · IEEE 1366EIA-861 Schedule 3 has two parts. Part B is for utilities that calculate SAIDI and SAIFI and determine major event days under IEEE 1366-2003 or IEEE 1366-2012; Part C is for any other method, where the utility also states how it defines a momentary interruption and whether inactive accounts count as customers. Figures from the two parts are not comparable and the atlas never pools them; utilities under Part C do not share one method either.Definition ↗

• Customers the indices are based on
  376,392 customers
• Highest voltage counted as distribution
  34.5 kV
• How it was measuredDetermined under IEEE 1366-2003 or IEEE 1366-2012; the form does not record which edition
  Outages recorded automatically: no
• Others reporting the same way · major event days included6 utilities in MT under IEEE 1366. Each counts once whatever its size; this is context, not a ranking.
  SAIDI median 296.9 (16.5–1,606.3) minutes/customer/yearSAIFI median 1.62 interruptions/customer/year
• Others reporting the same way · major event days excluded6 utilities in MT under IEEE 1366. Each counts once whatever its size; this is context, not a ranking.
  SAIDI median 147.6 (7.7–505.9) minutes/customer/yearSAIFI median 1.3 interruptions/customer/year

Reported by the utility on EIA-861 Schedule 3 under the method it declares. IEEE 1366 and other-method figures are not comparable, and values with and without major event days answer different questions. A system average says nothing about one address. CAIDI is published by EIA as SAIDI divided by SAIFI; it is not a line on the form. A value the utility left blank stays blank. Source and licence· Frozen facts for this utility ↗

Programme results as each utility filed them, by customer class and report year, each in its own unit. Classes are never added into a total, years are never added into a period, and savings are never divided by sales. The one ratio shown, enrolled demand-response customers against the utility's own EIA-861 customer count for the same state, class and year, carries both counts.

Energy efficiency EIA-861 Schedule 6 Part A

Reported by the utility on EIA-861 Schedule 6 Part A as adjusted gross savings at the customer meter under its own evaluation; figures are not comparable across utilities. Reporting-year incremental savings are annualized for participants new that year; life-cycle savings run over the programmes' planned life (energy as a lump sum, peak as the average annual reduction). Each class is shown as filed and the total row is the filer's own; nothing is summed here. Costs are nominal dollars of the report year (the form collects thousands; PUDL publishes dollars). A blank stays blank.

Demand response EIA-861 Schedule 6 Part B

Reported by the utility on EIA-861 Schedule 6 Part B. Potential peak savings assume every programme is called; actual peak savings are what was achieved at the company's own annual peak hour, and the two are never merged. Customers are enrolled customers, a count. Costs are nominal dollars of the report year. The form has no total row and none is computed here. A blank stays blank.

Population: organizations of this release with EIA-861 rows in the core states. A short-form respondent has no figures to file; a long-form respondent without a row may have no programmes or may have a nonutility administrator reporting for it. Years without a row are listed against the table's span, not against the years this utility filed the form.

Release 20260929T050546Z-51ae0f7d3c78 · Record JSON