Norochcholai coal power plant, which was shut down as a precaution following yesterday’s (17) islandwide power outage, will remain disconnected from the national grid for several days, the National System Operator (NSO) has announced.
In a statement, the NSO said the plant would remain offline while standard safety procedures were carried out following the incident.
The temporary loss of 810 megawatts of generating capacity would be managed through careful electricity supply arrangements to minimise the impact on consumers over the coming days, it said.
The NSO added that rainy weather would help maintain hydropower generation at maximum levels, while an expected relative decline in electricity demand was also likely to ease pressure on the power system.
The islandwide outage occurred at around 11.43 a.m. on October 17 after a generating unit disconnected from the national grid, triggering an imbalance that caused the entire power system to collapse in less than 30 seconds.
According to the NSO, restoration work began shortly afterwards. By 12.11 p.m., major hydropower generating units had been brought back online, and the power system was restarted simultaneously in four separate sections.
Despite challenges caused by small-scale power generation sources outside the direct control of the system control centre, restoration efforts continued through the activation of distribution feeders from 12.37 p.m.
By around 3.00 p.m., electricity had been restored to essential services, including major hospitals, water treatment plants and the airport. Grid substations across the country were reconnected by 5.00 p.m., restoring electricity to the majority of consumers.
The NSO noted that the disconnection of a generating unit as a safety measure was a normal occurrence at power plants. However, a complete collapse of the national power system following such a disconnection or another disruption was not considered normal.
An internal investigation has been launched to establish the sequence of events that led to the blackout and identify its underlying causes, the NSO said.
