The Transmission Company of Nigeria (TCN) said it fully restored the national power grid at 4:54pm on Saturday after a partial system collapse which occurred at 11.15pm on Friday.
TCN spokesperson, Ndidi Mbah, said during the entire period however, the nation did not experience full loss of power supply at once.
TCN said the incident was caused by the tripping of the Lokoja – Gwagwalada transmission lines 1 and 2 after a power swing whose cause is being traced.
The Onitsha – Alaoji transmission line also tripped due to too much current, the company said.
“These made the grid to operate in two parts, with the second part which is the Western and Northern axis experiencing outage. Efforts immediately commenced to bring the Western and Northern axis back into circuit, and as soon as that was almost complete, meaning supply was available most of the areas, the Eastern axis went out,” Mbah said in a statement.
The situation worsened after a fire incident at the Onitsha Substation, which necessitated the isolation of that substation, to save lives and properties.
However, TCN said it has continued the restoration of the Western/Northern axis, and the Eastern axis of the grid.
The shutting down of Onitsha substation caused tripping of some power stations connected to the grid, prolonging the partial collapse.
“There was no one time that the entire grid was down at the same time as TCN effectively utilized power from the generating stations not directly affected by the incident to attempt to stabilize the grid.”
TCN said the partial collapse occurred once and was only prolonged by technical hitches during the grid restoration.
