Electricity customers in the United States experienced an average of 11 hours of power outages in 2024, doubling the annual average observed over the previous decade. This significant increase is primarily linked to three major hurricanes – Beryl, Helene and Milton – which alone accounted for 80% of total hours without electricity, according to data from the U.S. Energy Information Administration.
Interruptions driven by extreme weather events
In 2024, outages attributed to major events averaged nearly nine hours, compared with an average of four hours per year from 2014 to 2023. Interruptions unrelated to exceptional events remained stable at about two hours annually. Utilities classify outages based on their origin: extreme weather conditions, vegetation interfering with lines, or internal system failures.
Outages are measured using two industry metrics: the System Average Interruption Duration Index (SAIDI) and the System Average Interruption Frequency Index (SAIFI). SAIDI measures the total duration of non-momentary outages experienced by a customer in one year, while SAIFI indicates the number of annual outages per customer.
Hurricanes hit Southeastern states hardest
South Carolina recorded the longest outages in the country, with nearly 53 hours per customer in 2024. When Hurricane Helene struck in September, more than 5.9 million customers lost power across ten states, including at least 1.2 million in South Carolina. High winds and flooding damaged distribution lines and substations, causing extended disruptions.
Texas was hit in July by Hurricane Beryl, which left 2.6 million people without electricity. In October, Hurricane Milton cut power to 3.4 million customers in Florida. North Carolina and Florida also suffered prolonged disruptions due to storm-related damage.
Wide disparities between states
Some states reported average outage durations of less than two hours, including Arizona, South Dakota, North Dakota and Massachusetts. In contrast, Hawaii experienced an average of 4.4 outages per customer – the highest rate nationwide. This frequency is attributed to severe weather, volcanic activity, unexpected failures at oil-fired plants, and challenges in integrating new generation capacity.
Northeastern states such as Maine and Vermont also had above-average outage frequencies, often due to storms causing trees to fall on power lines. In contrast, states like Maryland, Illinois and South Dakota reported fewer than one outage per customer in 2024.
