SriLanka, Nov. 1 -- The immediate cause of the islandwide power outage on October 17 was the loss of 187 megawatts of electricity from the national grid following the disconnection of the first generating unit at the Norochcholai Lakvijaya Power Plant, according to a preliminary investigation report submitted by the National System Operator (NSO) to the Public Utilities Commission of Sri Lanka (PUCSL).

The report states that at around 11.43 a.m. that day, the 187 megawatts generated by the first unit at Norochcholai was lost from the grid within 450 milliseconds. Although all five stages of the Under-Frequency Load Shedding (UFLS) mechanism were activated in an attempt to stabilise the system, the protective measures failed to prevent it...