CONTROL CENTRE BLAMES POOR PERFORMANCE ON OBSOLETE FACILITIES
The National Control Centre, Osogbo, has fingered obsolete generators, manual frequency control, low gas supply and system black-starting and a host of others as the cause of severe impediments currently being experienced in its operations.
The General Manager, NCC, Mr. Jonathan Ndiagwalukwe, while receiving the Minister of Power, Prof. Barth Nnaji, who visited to the centre recently, said that the Control Center, which is the nerve centre of all operations of the Power Holding Company of Nigeria, PHCN, is bedeviled generators that are old and ill maintained.
Despite recording a new peak generation of 3943.6MW recently, current generation fell again to about 3,300MW on account of poorly maintained facilities.
Ndiagwalukwe revealed that gas supply to thermal stations has been erratic and leading to shortfalls from the generating stations, thereby resulting in hiccups in operational planning, adding that there should be a firm commitment on gas supply between PHCN and NCC.
Dumping of substandard load
Speaking further on the challenges confronting the Center, he noted that the redial nature of the grid system subjects it to instability any time a critical and heavily loaded line trips leading to dumping of substantial load as there is no alternative supply route to the affected areas.
He also noted that frequent tripping of critical transmission lines is a major cause of system disturbance, adding that some critical transmission lines are single circuits, as a result, the centre cannot cater for maintenance needs, often leading to system collapse.
This, he explained, were the issues the Onitsha-Alaoja (T4A), Benin-Onitsha (B1T) 330KV lines and the inability to evacuate all the available generation in the Eastern part of the grid.
Ndiagwalukwe further said that the number of reactors for voltage control in the system is inadequate, saying, 'Some high voltage nodes like Birnin Kebbi and Onitsha have no reactors, the National Control Centre, Benin and Osogbo each requires an additional reactor to support the existing ones while the northern part of the country suffers from low voltage due to very long distance between the load centers and the generating stations.'
He, however, said that the Transmission Company of Nigeria, TCN has embarked on voltage stability study with a view to providing clues on how the problem can be solved.
The Centre boss further noted that the poor state of the distribution network makes it vulnerable to rainstorms, leading to high system frequency, a development that forces system controllers to shut down some generating units and reduce generation on some to keep the frequency under control.
He added that load allocation violations arising from the reluctance of distribution companies to respond to load shedding instructions also contribute to system collapse, saying, 'Stations hardly stick to their load allocation, compelling NCC operators to be constantly calling on people to come down to their allocation.'
He cited other challenges confronting the control centers to include communications and staffing, adding that the Supervisory Control And Data Acquisition, SCADA, which the Center uses for real time monitoring of power stations and substations, has a number of deficiencies.
He, therefore, appealed to the minister to turn around the crisis in the nation's power sector and create an environment for enhanced performance at the National Control Centers.