G 0.8 Power Supply Failure or Disruption

Despite high supply reliability, there are repeated interruptions in power supply by distribution network operators (DNO) or energy supply companies (ESC). The majority of these disruptions last less than one second and are so brief that humans do not notice them. However, interruptions lasting more than 10 ms are capable of disrupting IT operations. In addition to disruptions in the supply network, unannounced work shutdowns or cable damage from excavation work can also cause power supply failures.

Power supply does not only affect the obvious, direct power consumers (PCs, lighting, etc.). Many infrastructure systems today depend on electricity, such as elevators, climate control, alarm systems, security doors, automatic door closing systems, and sprinkler systems. Even water supply in high-rise buildings depends on electricity because of the pumps required to generate pressure in upper floors. During prolonged power outages, the failure of infrastructure systems can result in no activities being possible in the affected areas.

In addition to outages, other power supply disruptions can impair operations. Overvoltage, for example, can cause malfunctions or even damage to electrical equipment.

It should also be noted that power supply outages or disruptions in the neighborhood can potentially affect your own business processes, for example, if access roads are blocked.

Examples:

• Due to an error in the UPS of a data center, it did not return to normal operation after a brief power failure. After the batteries were discharged (after about 40 minutes), all computers in the affected server room failed.
• In early 2001, California experienced a power shortage lasting over 40 days. The power supply situation was so strained that the California Power Grid Operator instituted rolling blackouts. These blackouts, which lasted up to 90 minutes, affected not only households but also the high-tech industry. Because alarm systems and surveillance cameras were also turned off by the power outage, the power supply companies kept their shutdown plans secret.
• In November 2005, after heavy snowfalls in Lower Saxony and North Rhine-Westphalia, many municipalities were without power for days because many high-voltage pylons collapsed under the weight of snow and ice. Restoration of power supply took several days.