Sun Prairie Utilities

What This Utility Data Tells You

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.