Nigeria's paltry on-grid  electricity supply capacity is to drop by about 300 megawatts (MW), the Transmission Company of Nigeria (TCN) has said.

TCN stated in a statement yesterday in Abuja that the unavoidable drop in the quantity of power available for it to transmit to the distribution companies would be as a result of an expected shutdown of the Shiroro Hydro Power Plc.

The statement, which was signed by the Head of Public Communication of TCN, Seun Olagunju, explained that the drop would mostly affect northern states.

It noted that the power plant had notified it of the imminent shutdown for three days, starting from today to Wednesday.
"The shutdown of the station is to enable the engineering maintenance crew of the Shiroro power station rectify ground fault on the station's carbon dioxide control panel which provides vital auxiliary services necessary for the running of the power plant," the statement explained.

It further stated that the control panel was a fire protection scheme for all the units in the power station and that if it was out on repairs, all the units in the station would have no protection against fire outbreak, hence the need to shut down all the units of the power plant.
"During the period, grid generation will reduce by 300MW, hence the nationwide load shedding.

The impact of the load shedding would be higher in the northern axis of the nation, especially Kano, due to voltage instability issues previously affecting power supply in that axis," it added.

TCN however apologised for the inconvenience that the planned load shedding would cause the federal government and electricity consumers nationwide during the period.

It assured Nigerians that it would continue to work with the power generating stations and distribution companies nationwide to improve and stabilise the power supply situation of the nation which has continued to dip from such issues as shortage of gas stock to thermal power plants amongst others.

With this expected drop from Shiroro, total nationwide power supply will likely stay at about 2,900MW from about 3,200MW that was last week broadcast from the National Control Centre in Osogbo, Osun State.

Meanwhile, the gas-powered generating plants nationwide have been operating below half of their available capacities in recent weeks, with electricity supply fluctuating, following shortage of gas from the Nigerian Gas Company (NGC), a subsidiary of the Nigerian National Petroleum Corporation (NNPC).

The NNPC, however, said the drop in gas supply for power generation was due to rising incidents of outright sabotage of some crucial gas pipelines, which have significantly eroded available gas supply to the power plants.

The Group Managing Director of the Corporation, Mr. Andrew Yakubu, said over 30 per cent or 480 million standard cubic feet per day (MMsf/d) of the installed gas supply capacity, the equivalent to the gas requirement to generate about 1,600MW of electricity, was out due mainly to vandalism. 

But with the planned shutdown of the Shiroro Hydroelectric Power Station, which has been contributing about 409megawatts at peak generation and 300megawatts at off peak, the supply of electricity will worsen, at least, in the next three days.

The NNPC had listed the gas pipelines involved in vandalism to include, the Escravos-Warri stretch of the Escravos Lagos Pipeline System (ELPS) which accounts for 190mmcf/d, and the Trans-Forcados crude pipeline, which accounts for 230mmcf/d.

The remaining gas supply shortfall, according to the corporation, is due to maintenance issues at Utorogu gas plant, which accounts for 60mmcf/d.