Blackouts

A blackout (also power cut, power outage, or power failure) is a short- or long-term loss of the electric power to an area.
There are many causes of power failures in an electricity network.Examples of these causes include faults at power stations, damage to electric transmission lines, substations or other parts of the distribution system, a short circuit, or the overloading of electricitymains.
Power failures are particularly critical at sites where the environment and public safety are at risk. Institutions such as hospitals, sewagetreatment plants, mines, and the like will usuallyhave backup power sources such as standby generators, which will automatically start up when electrical power is lost. Other critical systems, such as telecommunications, are also required to haveemergency power. Telephone exchange rooms usually have arrays of lead-acid batteries for backup and also a socket for connecting a generator during extended periods of outage.-------------------------------------------------
Protecting computer systems from power outages
Computer systems containing logic circuitry are susceptible to data loss or hardware damage that can be caused by the suddenloss of power, the use of an uninterruptible power supply or UPS can provide a constant flow of electricity in the event that a primary power supply becomes unavailable for a short period of time. Historical blackouts
The most severe blackouts concerning affected population and duration were:
U.s.a. (north-east) + Canada (central)
14.08.2003 (detailed description see Annex)
A combination oflack of maintenance, human error and equipment failures caused an outage that affected large portions of the Midwest and Northeast United States and Ontario, Canada. This area typically has a totalelectric load of 61,800 MW. The blackout began a few minutes after 4:00 pm Eastern Daylight Time and power was not restored for 4 consecutive days in some parts of the United States.
Duration 4 days...