The Transmission Company of Nigeria (TCN) has given reasons why public power supply across the entire country went off on Thursday night.
According to the TCN, generation outages from three units of Egbin power plant on that night resulted in a total collapse of the electricity system, hence the outage.
It said in a statement on Friday in Abuja, that at about 8:03pm on Thursday, its supervisory control and data acquisition (SCADA) system picked up the development, adding that restoration of generation and supplies to the grid however started at about 8:22pm.
“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 20:22hrs,” said the statement.
The TCN further explained that a post mortem analysis of the event indicated that grid generation was shortened to about 4,262.7 megawatts (MW) prior to the inception of the disturbance which it added was due to capacity under-utilisation and the fact that operational capability required to maintain grid stability had waned thus leaving the system vulnerable to the extent that distresses of such 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,” it added.
Following from the lack of spinning reserves to jumpstart the system during instances of such collapse, TCN stated that it had applied to the Nigerian Electricity Regulatory Commission (NERC) for an extraordinary tariff review to incentivise power generation companies (Gencos) to provide such services.
It stated: “In order to avert such incidence on a sustainable basis, the Transmission Company of Nigeria has filed an application to the Nigerian Electricity Regulatory Commission for an extraordinary tariff review as a means of ensuring that generation companies are incentivised to provide sufficient spinning reserves and other ancillary services that are critical for managing the national grid.
“The Transmission Company of Nigeria hereby solicits for the understanding of all Nigerians as we continue with our 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.”