Power Outage

What Does Power Outage Mean?

A power outage is a short- or long-term state of electric power loss in a given area or section of a power grid. It could affect a single house, building or an entire city, depending on the extent of the damage or cause of the outage.


A power outage is also known as power failure, power blackout or simply as blackout.

Techopedia Explains Power Outage

Power failures in an electric network can be caused by different factors, but the most common are often faults in the power lines and in the distribution stations themselves. Only very rarely are the power plants themselves at fault since these systems are built to withstand minor disasters and have various backup facilities that kick in when the main system goes offline for some reason.

Smaller power distribution facilities have fewer (or no) backup systems because they are cheaper and simpler to repair. However, the number one cause of power outages is the power lines themselves, since they are the most vulnerable and least protected elements in a power grid, especially in areas where it is not feasible to hide them underground, such as in between large stretches of uninhabited land or rural areas without large sewer systems.

Types of power outage:

  • Brownout — This is simply a phenomenon where the voltage in the system drops, and it is characterized by the dimming of lights, hence the name. This can cause incorrect performance in electrical equipment.
  • Blackout — A total loss of power in an area due to damage in the power grid, from the power stations to the power lines. The outage can last from a few minutes to an indeterminate amount of time, depending on the extent of damage. In places affected by great natural disasters that completely destroy the electric grid system, it can take months to restore power.

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Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.