The nation’s electricity grid system faced a total collapse on Thursday, the Transmission Company of Nigeria announced on Friday.
It, however, stated that the restoration of the grid was at an advanced stage and explained that the total collapse was due to tripping of three generator units at the Egbin power generation station in Lagos.
The daily report on the power sector that was made available to our correspondent by the TCN on Friday stated that the grid collapsed totally on Thursday, September 28, 2017, after the country generated 3,515 megawatts of electricity the preceding day.
The TCN said, “A total system collapse was recorded on September 28, 2017 at 20:03hours. Reports obtained from stations and the sequence of events generated by the SCADA system indicated that the system collapse was triggered by the tripping of Egbin Units ST4, ST6 and ST5 at 20:03:15, 20:03:32 and 20:03:34, respectively.
“By this incident, the Nigerian electric power grid lost generation completely before restoration commenced at 20:22hours.”
The power transmission firm stated that a post mortem analysis of the event indicated that grid generation was curtailed to about 4,262.7MW prior to the disturbance due to capacity under-utilisation, as the operational capability required to maintain grid stability had waned.
This, it said, left the system vulnerable to the extent that perturbations of this magnitude resulted in severe system frequency dip that culminated in system collapse.
“The analysis clearly indicated that there was insufficient level of spinning reserve provided by grid-connected generation companies arising from low tariffs for providing ancillary services,” the TCN added.
In order to avert such an incidence on a sustainable basis, the firm stated that it had filed an application to the Nigerian Electricity Regulatory Commission for an extraordinary tariff review.
It said this would serve as a means of ensuring that generation companies were incentivised to provide sufficient spinning reserves and other ancillary services critical for managing the national grid.
The firm solicited for the understanding of all Nigerians and promised to continue with efforts to provide the electricity industry with a world class national grid.
“On our part, we will strive to ensure that the stride attained recently in frequency control is sustained in line with world industry standards and codes,” it added.