Cyber Risk Compendium

Power failure or disruption

BSI ID: G 0.8

Despite high supply reliability, power supply interruptions occur repeatedly on the part of distribution network operators (DNOs) and energy supply companies (ESCs). Most of these disruptions last less than a second and are so short that they go unnoticed. However, even interruptions of more than 10 ms are enough to disrupt IT operations. In addition to disruptions in the supply network, unannounced shutdowns or cable damage during civil engineering work can also cause power failures.

It is not only obvious, direct consumers of electricity (PCs, lighting, etc.) that are dependent on the power supply. Many infrastructure facilities are now dependent on electricity, e.g. lifts, air conditioning, hazard warning systems, security gates, automatic door closing systems and sprinkler systems. Even the water supply in high-rise buildings is dependent on electricity because of the pumps required to generate pressure in the upper floors. During prolonged power outages, the failure of infrastructure facilities can mean that no work can be carried out in the affected premises.

In addition to outages, other power supply disruptions can also impair operations. Overvoltage, for example, can lead to malfunctions or even damage to electrical equipment. It should also be noted that power failures or disruptions in the neighbourhood may also affect your own business processes, for example if access routes are blocked.

Examples:

  • Due to a fault in the UPS of a data centre, it did not switch back to normal operation after a short power failure. After the batteries were discharged (after about 40 minutes), all computers in the affected server room failed.

  • In early 2001, there was a power emergency in California that lasted over 40 days. The power supply situation there was so tense that the California Independent System Operator ordered rotating power outages. These power outages, which lasted up to 90 minutes, affected not only households but also the high-tech industry. Because the power outage also shut down alarm systems and surveillance cameras, the energy suppliers kept their shutdown plans secret.

  • In November 2005, after heavy snowfall in Lower Saxony and North Rhine-Westphalia, many communities were without power for days because many high-voltage pylons had collapsed under the weight of snow and ice. It took several days to restore power.