Annual Probability of Extended Power Outage

The average US electricity customer experiences about 1.5 power outages per year, with a total duration of about 8 hours. Approximately 30% of customers experience at least one outage lasting more than one hour in a given year. Extended outages (lasting 24+ hours) affect about 5-10% of customers annually.

Weather events are the leading cause of power outages, accounting for about 67% of all major outages. This includes severe storms, hurricanes, ice storms, extreme heat (which can cause equipment failures and rolling blackouts), and wildfires. Equipment failure accounts for about 20% of outages, and human error (including vehicle accidents involving power poles) causes about 8%.

Power outage frequency and duration have been increasing in the United States. Major weather-related outages (affecting 50,000+ customers) have increased by about 67% since 2000, largely attributed to aging grid infrastructure, more extreme weather events, and increased electricity demand. Preparation measures include maintaining flashlights and batteries, having a battery-powered radio, keeping devices charged, having a backup power source (generator or battery backup), and maintaining an emergency water and food supply. Extended outages pose particular risks for those dependent on electric medical equipment.