One of the nation’s three hydropower plants, Shiroro Power Station, has been shut down as a result of flood problem, with seven thermal plants left idle by gas constraints and other issues.

Shiroro, which generated a high of 428 megawatts on January 3, 2018, was said to be “out due to turbine pit flood problem.”

Data obtained from the Federal Ministry of Power, Works and Housing on Sunday showed that the plant had been idle since February 20.

The nation generates most of its electricity from gas-fired power plants, while output from hydropower plants makes up about 30 per cent of the total generation.

Total electricity generation stood at 4,455.5MW as of 6am on February 28, while 2,139.6MW was unutilised generation capacity, the latest data from the ministry showed.

The number of power plants idle as of the end of February was eight, comprising Sapele I, AES, ASCO, Azura-Edo and three plants built under the National Integrated Power Project scheme – Alaoji, Ihovbor and AES.

Sapele’s ST1 unit tripped on low drum level; ST2 out on maintenance; ST3 out on stator winding problem; ST4 and 5 awaiting major overhaul; and ST6 tripped on gas control valve not following reference point.

Alaoji’s GT1, 2 and 4 tripped due to low gas pressure, and GT3 was shut down due to generator air inlet filter trouble.

Two units, GT1 and 2, at Ihovbor were said to be out due to gas constraint while GT3 and 4 were reportedly out on maintenance.

Gbarain’s GT2 was out due to gas constraint. The AES has been out of production since November 27, 2014, while the ASCO’s GT1 was shut down due to leakage in the furnace.

The GT11 of Azura-Edo Independent Power Plant, which was recently synchronised with the national grid, was said to be undergoing tests, while GT12 and 13 are awaiting inauguration.