Yesterday I came across this cool video posted to YouTube from Florida Power and Light. In 2001, an electrical substation in Miami short-circuited and blew up – and all of it was caught on tape by a FPL employee. Watch as the high voltage slices through the substation, finishing itself off in a massive fireball. It reminds me of the fire at the substation at the corner of Martin Luther King Boulevard and East Street in 2001.
What’s great about this video is the extensive commentary included with it, which explains exactly what happens when the substation melts down:
In early 2001, the Ives Dairy Substation in Miami, Florida experienced a total system failure. It started with the simple failure of a capacitor bank (a piece of equipment used to synchronize and optimize varying electrical currents “phases” coming off the main power grid before being distributed to customers).
This short circuit caused a breaker to trip open, however it malfunctioned and created an arc fault (a continuous lightning bolt that acted like an uncontrollable welding torch from hell) between the hot lead and wherever it could find a ground, thus pulling far more current then the facility was designed for.
One of the first things that the arc fault destroyed was the emergency response system that would have notified the grid dispatcher of a serious problem (who would have then cut the power to the substation to kill the arc fault). Since the emergency system fried first in the arc fault, no signal was ever sent to the dispatcher, and the substation continued to self-destruct.
The uncontrolled arc fault caused the coolant (mineral oil) inside the primary transformer to overheat to critical levels until it was boiling in a highly flammable state. This boiling caused pressure to rise inside the transformer (like a pressure cooker) until the seals finally blew. Mineral oil vapor proceeded to pour out at that point (the plume of white fog at the end) which ignited on the arc fault. The flames caused by this immediately ignited back to the source, (the boiling transformer tank), which ignited the mother load of oil inside causing the substation to explode in a giant ball of fire.
The sudden loss of all transformer coolant resulted in a simultaneous flash-meltdown of the transformers innards, which immediately caused the main high voltage fuse to overload and blow (the loud explosion at the end), finally killing the arc.
I love watching technology go bad.