The Trinidad and Tobago Electricity Commission says at approximately 3:00 pm, during the course of maintenance work at its Toco Substation, a fault occurred which caused the generating units at the Cove Power Station in Tobago to trip, triggering a cascading effect across the island.
The entire island subsequently lost supply.
Ninety-five percent of the customers were back on supply at approximately 4:30 p.m. and restoration work is ongoing.
The root cause of the initial fault is being investigated.