Municipal · Wisconsin · EIA 18312

Sun Prairie Utilities

Municipal · Wisconsin · 18K customers. According to the U.S. Energy Information Administration's EIA Form 861, reliability for 2023 shows SAIDI 17 minutes/customer.

Reliability verdict

Sun Prairie Utilities shows above-average chronic reliability in 2023: 17 minutes SAIDI excluding major events across 18K customers.

17 min
SAIDI 2023
0.44
SAIFI 2023
17 min
SAIDI ex-MED
18K
Customers

Chronic reliability judged on SAIDI excluding major event days when reported (IEEE 1366). Source: EIA Form 861 · August 2026.

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Signature read: short interruption minutes vs the 911 utility cohort (≤96 min tercile cut).

What short-outage Sun Prairie Utilities filings show

Sun Prairie Utilities is a municipally-owned utility operating in Wisconsin under EIA identifier 18312. It reports service to approximately 18,263 customer accounts and generated about $0.03 billion in annual electric revenue, with a service footprint spanning 3 ZIP codes. As a municipal utility, it is typically governed by a local board or city council and is exempt from federal income tax.

In 2023, the average Sun Prairie Utilities customer experienced 16.9 minutes of power interruptions, the industry-standard SAIDI metric (System Average Interruption Duration Index). That is comfortably under the 120–180 minute national benchmark range, a sign of solid grid resilience and quick outage response. The SAIFI figure, which tracks average outage events per customer, came in at 0.44 for the same period, meaning customers statistically saw about 0 distinct interruptions that year. Excluding major event days (hurricanes, ice storms), SAIDI drops to 16.9 minutes, the gap between that figure and the headline 16.9 reveals how much weather, not day-to-day infrastructure, drove outages.

Sun Prairie Utilities has 3 years of continuous EIA reporting on file (2021–2023), enough to read a real trend rather than a single-year snapshot. Over that span, SAIDI rose from 12.7 to 16.9 minutes, possibly reflecting tougher weather years or grid upgrades that have not caught up yet.

A+
Reliability Score
91/100
Sun Prairie Utilities · 3 of 3 dimensions reported

Based on this utility's own EIA Form 861 reliability record -- baseline (major-event- excluded) outage duration, total outage duration, and outage frequency -- each benchmarked against every reporting utility nationwide. Not a measure of electricity rates or customer service, which this portal does not track.

Baseline Reliability A+ 16.9 min/yr
SAIDI excluding major-event days — day-to-day grid performance
Total Outage Duration A+ 16.9 min/yr
SAIDI including storms and major events — the full-year experience
Outage Frequency A 0.44/yr
SAIFI — average number of interruptions per customer per year
SAIDI vs. national mean (341 min) 2.2%

17 minutes per customer per year

Sun Prairie Utilities SAIDI

Power-out minutes per year (2023)

17 SAIDI17 SAIDINat. avg 341341SAIDI17SAIDI

Excellent

SAIDI by year (2021-2023)

Minutes per customer-year · EIA Form 861

Year-by-year SAIDI for Sun Prairie Utilities from the same EIA filings as the table below. Lower is better; major-event years can spike the headline figure.

Source: U.S. EIA Form 861 As of August 2026

Sun Prairie Utilities SAIDI trend

0 5 10 15 20 25 2021 2022 2023 12.7 20.7 16.9
Year-by-year SAIDI from the same EIA filings as the table below. Lower is better; major-event years can spike the headline figure.

Sun Prairie Utilities vs the nationwide SAIDI distribution

Where this utility's headline SAIDI sits among every EIA Form 861 utility with a reported figure

17 Among the lowest fewer outage minutes than 95% of 911 utilities

Utilities nationwide, banded by latest reported SAIDI (minutes)

Each bar is a band; taller bars hold more utilities. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source U.S. EIA Form 861 reliability filings · August 2026

Price vs. reliability

Where Sun Prairie Utilities sits on price vs. reliability

Among the 781 U.S. utilities large enough to report both revenue per customer and a recent outage record, Sun Prairie Utilities charges more per customer than 3% of them, and is more reliable (lower SAIDI) than 96% of them, placing it in the quadrant where it pays less while still being more reliable, the best-value quadrant. Revenue per customer and outage minutes are independent figures: paying more does not guarantee fewer outages.

Sun Prairie Utilities vs. a 40-utility national peer sample, price percentile vs. reliability percentile. Scatter plot of 41 data points (bubble-sized by third dimension). 050100150 050100150 Best valuePays for itCheap + riskyWorst deal Price percentile Reliability percentile Point, Price percentile: 0 · Reliability percentile: 22Point, Price percentile: 3 · Reliability percentile: 35Point, Price percentile: 8 · Reliability percentile: 5Point, Price percentile: 10 · Reliability percentile: 15Point, Price percentile: 13 · Reliability percentile: 75Point, Price percentile: 15 · Reliability percentile: 95Point, Price percentile: 18 · Reliability percentile: 12Point, Price percentile: 20 · Reliability percentile: 52Point, Price percentile: 23 · Reliability percentile: 10Point, Price percentile: 25 · Reliability percentile: 25Point, Price percentile: 28 · Reliability percentile: 47Point, Price percentile: 30 · Reliability percentile: 100Point, Price percentile: 33 · Reliability percentile: 32Point, Price percentile: 35 · Reliability percentile: 60Point, Price percentile: 38 · Reliability percentile: 30Point, Price percentile: 40 · Reliability percentile: 37Point, Price percentile: 43 · Reliability percentile: 65Point, Price percentile: 45 · Reliability percentile: 43Point, Price percentile: 48 · Reliability percentile: 0Point, Price percentile: 50 · Reliability percentile: 7Point, Price percentile: 53 · Reliability percentile: 72Point, Price percentile: 55 · Reliability percentile: 80Point, Price percentile: 57 · Reliability percentile: 85Point, Price percentile: 60 · Reliability percentile: 70Point, Price percentile: 63 · Reliability percentile: 2Point, Price percentile: 65 · Reliability percentile: 62Point, Price percentile: 68 · Reliability percentile: 90Point, Price percentile: 70 · Reliability percentile: 67Point, Price percentile: 73 · Reliability percentile: 45Point, Price percentile: 75 · Reliability percentile: 40Point, Price percentile: 78 · Reliability percentile: 87Point, Price percentile: 80 · Reliability percentile: 17Point, Price percentile: 83 · Reliability percentile: 92Point, Price percentile: 85 · Reliability percentile: 27Point, Price percentile: 88 · Reliability percentile: 20Point, Price percentile: 90 · Reliability percentile: 77Point, Price percentile: 93 · Reliability percentile: 55Point, Price percentile: 95 · Reliability percentile: 82Point, Price percentile: 98 · Reliability percentile: 57Point, Price percentile: 100 · Reliability percentile: 50Sun Prairie Utilities, Price percentile: 3 · Reliability percentile: 96
Sun Prairie Utilities vs. a 40-utility national peer sample, price percentile vs. reliability percentile.

Revenue per customer: $1,674/year · Latest SAIDI: 16.9 minutes/year.

SAIDI 2023 breakdown: 16.9 minutes

Reliability Trend (2021–2023)

Year SAIDI (min) SAIDI nMED SAIFI Customers
2021 12.7 12.7 0.510 16,828
2022 20.7 20.7 0.520 17,382
2023 16.9 16.9 0.440 18,262

SAIDI nMED = SAIDI without major event days. Source: EIA Form 861.

Service Area

Sun Prairie Utilities serves 3 ZIP codes in Wisconsin.

535325359053596

Frequently Asked Questions

How reliable is Sun Prairie Utilities?

Sun Prairie Utilities had a SAIDI of 16.9 minutes in 2023. Excluding major storm impacts, this beats the national average, a sign of above-average reliability.

What type of utility is Sun Prairie Utilities?

Sun Prairie Utilities is classified as a Municipal serving Wisconsin.

How many customers does Sun Prairie Utilities serve?

Sun Prairie Utilities serves approximately 18,263 customers in Wisconsin.

How has Sun Prairie Utilities's reliability changed over time?

Sun Prairie Utilities has 3 years of reliability data (2021-2023). This utility's SAIDI has stayed fairly flat over the period. Review the trend table above for year-by-year detail.

Utility Profile

Type
Municipal
State
Wisconsin
Customers
18,263
Annual Revenue
$0.03B
EIA ID
18312

Utilities with similar EIA profiles

Two cross-state peer sets for Sun Prairie Utilities. Same-state SAIDI neighbors stay in Read-with below; these neighborhoods are nearest other-state utilities with at least 10,000 reported customers.

Similar customer count

Nearest utilities by Form 861 customers (18K here), outside Wisconsin.

Similar chronic SAIDI

Nearest utilities by latest SAIDI minutes (16.9 here), outside Wisconsin, excluding the customer-peer set.

Source: U.S. Energy Information Administration Form 861 annual electric power industry survey · ZIP service territory: OpenEI. Disclaimer: informational only, not professional advice. See full disclaimer · methodology.