Substation explosion and fire causes major blackout across northern Puerto Rico

What happened

On Sunday 11 February 2018, an explosion and fire at an electric substation in Puerto Rico caused a widespread blackout. The Puerto Rico Electric Power Authority (PREPA) told the Associated Press that much of northern Puerto Rico, including parts of the capital, San Juan, and the municipalities of Guaynabo, Carolina and Juncos, was left without power. PREPA hoped power would be restored within a day. The outage came five months after Hurricane Maria caused the longest blackout in United States history, and it was reported as a setback to efforts to restore power on the island. The San Juan mayor posted an update saying the fire had almost totally been extinguished and the cooling phase was beginning.

Contributing factors

PREPA officials told CNN that the fire was caused by a mechanical failure. The source notes that Puerto Rico's power grid was already vulnerable, with PREPA's power plants averaging 44 years old, compared with an industry average of 18 years.

Lessons learned

1. Ageing grid infrastructure can fail catastrophically and should be prioritised for inspection and replacement.
2. Substations need fire suppression and cooling arrangements that can contain a failure and prevent it spreading to adjacent equipment.
3. Operators recovering from a major storm should plan for secondary failures on equipment that has already been stressed.

More lessons on maintenance, inspection and ageing assets, fire suppression and firefighting, weather and external hazards, from every incident on the register.

Source

time.com