Which of the following best describes a blackout?

A blackout refers to a condition in which a significant portion or all of an electrical network loses power and is effectively de-energized. This can occur due to a variety of factors such as system overloads, equipment failures, or major faults in the network. In such a scenario, the vast majority of consumers connected to the grid experience a loss of electricity, which can result in widespread disruption of services and impacts on daily life.

In contrast, other options describe situations that are not as severe as a blackout. A temporary power interruption in a specific area indicates a localized event rather than a widespread network failure. An outage caused by maintenance work on power lines is generally planned and does not typically result in a complete loss of network functionality. Lastly, a minor fault within a transmission line usually implies a limited impact, often rectified without leading to a complete disconnection of power across a large area. Hence, the definition encompassing a major or total de-energization of the network aligns best with the definition of a blackout.