Grid reliability · 2024 · 10 reporting utilities

Power outages in North Dakota

The utilities that reported here serve 406,369 customers between them, not the whole state. Weighted by customer count, they averaged 87 min without power in an ordinary year and 103 min once major events are counted. Each figure comes only from the filers that published it, and the counts are below.

What it means

Why there are two numbers

Across the utilities that filed both figures, major events account for 15% of the outage time North Dakota recorded once they are counted: 103 min against 87 min without them, a factor of 1.2×. Solar panels alone do not help during an outage, because a grid-tied array shuts down when the grid does, so riding through one is a battery question. This figure will not answer it: it is an annual average across a utility’s customers, not the length or the load of any single outage. What it does say is how much of the outage time here arrives with major events rather than on ordinary days.

The comparison is drawn from the 10 utilities that filed both figures, which is all of them, so both sides of the ratio describe the same set of customers. The two headline figures above are averaged over everyone who filed each one, so dividing them would not give this number.

Ordinary year87 min37 of 51 jurisdictions, longest first · 10 filings
With major events103 minStorms, ice, and fires included as filed · 10 filings
Interruptions a year0.9×Ordinary year; 0.9× with major events
The bill sideWhat solar offsetsRates and modelled output by utility

The utilities behind the average

Each of North Dakota’s figures is a customer-weighted average of the filings that carried that metric, not of the table as a whole: the ordinary-year average is built from 10 filings and the storm-inclusive average from 10 filings, out of 10 filings that published an outage figure at all. Those are the same utilities on both sides. A utility that filed without publishing a metric, or whose two major-event variants contradicted each other, is absent from that metric rather than counted as zero.

Reported interruption metrics for 2024, largest utility first.
UtilityCustomersOrdinary yearWith major eventsInterruptions
Montana-Dakota Utilities Co98,01779 min83 min0.9×
Northern States Power Co - Minnesota95,75455 min55 min0.6×
Otter Tail Power Co59,7612.2 hr2.8 hr1.1×
Cass County Elec Coop Inc58,76224 min24 min0.4×
Nodak Electric Coop Inc21,561108 min108 min1.0×
Verendrye Electric Coop Inc20,67737 min37 min0.7×
Mountrail-Williams Elec Coop19,1032.4 hr4.7 hr1.1×
McKenzie Electric Coop Inc13,5463.5 hr4.3 hr1.6×
Northern Plains Electric Coop12,2254.4 hr4.4 hr1.9×
Dakota Valley Elec Coop Inc6,9633.1 hr3.7 hr1.6×

What this page is not

It is a state average of utility filings, not a measurement at any address. Each filing is itself an average over a whole service territory, so a rural feeder and a downtown network arrive here as one number, and nothing in this dataset says how far an individual address sits from it. Nothing here predicts a future year either, and a single severe storm can move a utility’s figure by an order of magnitude.

The methodology page states the sources, the definitions, and the limits. Back to the Grid Reliability Index

Source: U.S. Energy Information Administration, Form EIA-861 reliability file, data year 2024, covering 2024-01-01 through 2024-12-31. The snapshot covers no later period.