The California Independent System Operator (CaISO) has declared a Flex Alert for the southern San Francisco Bay Area after unknown vandals caused heavy damage to a substation in San Jose. The Flex Alert covers the Silicon Valley area and Santa Clara County and is expected to last until midnight tonight.
Flex Alerts are usually announced during expected periods of heavy power consumption, and generally consist of the grid operator asking consumers to avoid running heavy appliances such as washing machines and air conditioners.
CaISO and Pacific Gas & Electric (PG&E) report that unknown vandals fired shots at transformers at the Metcalf transmission substation, an important node in the local transmission grid that's just south of San Jose proper. Bullet holes in transformers caused cooling fluid leakage; as PG&E assesses the damage to the substation the utility will need to take equipment offline, potentially causing temporary power shortages.
In addition to delaying loads of laundry and other power-hungry tasks, CaISO is asking San Jose-area residents and businesses to turn off lighting that's not strictly necessary and take other common-sense measures to reduce demand on the grid.
Just another reminder of how fragile our current power distribution system really is, vulnerable to acts of both Nature and bored vandals with guns.