Interstate Power and Light Co

What This Utility Data Tells You

Interstate Power and Light Co is a investor-owned utility operating in Iowa under EIA identifier 9417. It reports service to approximately 501,812 customer accounts and generated about $1.67 billion in annual electric revenue, with a service footprint spanning 500 ZIP codes. As an investor-owned utility, it operates under state public utility commission oversight that reviews rate cases and reliability performance.

In 2023, the average Interstate Power and Light Co customer experienced 149.4 minutes of power interruptions — a metric called SAIDI (System Average Interruption Duration Index). That sits within the 120–180 minute national benchmark range, indicating performance typical of U.S. distribution utilities. SAIFI — the average number of outage events per customer — was 1.00 for the same period, so customers statistically faced roughly 1 distinct interruption that year. Excluding major event days (hurricanes, ice storms), SAIDI drops to 88.2 minutes — the gap between that figure and the headline 149.4 reveals how much weather, not day-to-day infrastructure, drove outages.

The EIA dataset includes 4 years of continuous reporting (2020–2023) for Interstate Power and Light Co, which lets you see whether reliability is trending up or down rather than judging from a single snapshot. SAIDI has improved from 3180.0 to 149.4 minutes over that window — a meaningful direction for prospective customers and regulators watching capital investment outcomes. All figures on this page come directly from EIA Form 861, the federal annual electric power industry survey, with service territory ZIPs sourced from OpenEI — you can cross-reference them with your own utility bill or use them when comparing providers before relocating.