TCN pushes back on GenCos’ “stranded power”, claims, 8,700MW wheeling capacity

By Onu Okorie

Transmission Company of Nigeria TCN has rejected claims by the Association of Power Generation Companies APGC that Nigeria is losing over 2,500 megawatts of power daily because the national grid cannot carry what generators produce, arguing that the Nigerian Electricity Regulatory Commission’s NERC own First Quarter 2026 Report tells a different story.

The dispute follows a 28 July media report in which APGC was quoted describing Nigeria’s power shortage as “a transmission failure, not a generation failure,” claiming more than 15,500MW of installed generation capacity is being throttled by a grid that can wheel only around 4,500MW.

In a detailed response, TCN said the same NERC report both sides are drawing from shows the opposite: that the “gap” in Nigeria’s power supply originates largely at the power stations, not on the transmission network.

According to TCN, NERC’s data puts total installed capacity across the 28 grid-connected plants at 13,625MW, nearly 1,900MW short of the figure APGC cited. More significantly, the company said the “4,500MW” ceiling APGC attributes to the grid actually matches the average capacity GenCos themselves declared available for dispatch during the quarter, a number set by generators reporting to the market, not by any transmission constraint.

TCN said its verified wheeling capacity is in fact 8,700MW, and pointed to real-world performance as evidence: on 4 March 2025, the grid carried a record 5,801.84MW, delivering the highest single-day energy volume in Nigerian history, alongside similar peaks in the same week. A network limited to 4,500MW, the company argued, could not physically have carried those volumes.

TCN also cited an ongoing expansion programme, including 82 new power transformers commissioned between January 2024 and November 2025, adding roughly 8,500MVA of capacity, along with reconductoring projects on several transmission corridors. It highlighted new 330kV lines linking Ihovbor to Benin and Ajaokuta, commissioned in April 2026, which it said opened up more than 600MW of additional evacuation capacity for two major power plants in the Niger Delta.

TCN pointed to NERC’s Plant Availability Factor (PAF) table, which recorded fleet-wide availability of just 32.72% for the quarter — meaning more than two-thirds of installed capacity was unavailable for dispatch regardless of grid capacity. Several plants recorded availability near zero, including one 500MW facility that was offline for the entire quarter.

The company noted that APGC’s own chief executive acknowledged, elsewhere in the original report, that gas supply to thermal plants had fallen below 43% of daily requirement — a statement TCN said corroborates NERC’s availability data rather than supporting the transmission-failure narrative.

TCN further argued that NERC’s load factor data undercuts the “stranded power” claim directly: at 92.26% for the quarter, only about 7.74% of declared available capacity went undispatched — roughly 345MW, far below the 2,500–4,000MW APGC says is stranded daily. Five plants, it noted, had their full declared output dispatched, recording load factors of 100%.

On transmission losses, TCN said NERC’s audited figures show a 7.96% Transmission Loss Factor, equivalent to about 327MW of average hourly loss, well below the 1,200–1,300MW daily figure cited in the original report. It also argued that the bulk of the ₦2.61 billion in related costs for the quarter stemmed from a GenCo capacity penalty rather than actual line losses.

On the widely cited ₦2.28 trillion in unpaid capacity payments, TCN argued this is better explained as a commercial collection problem among distribution companies (DisCos) than an evacuation failure, pointing to NERC’s finding that DisCos posted commercial losses more than double their regulatory target, alongside a ₦24.95 billion shortfall in remittances to the market.

On the dramatic grid collapse of 27 January 2026, when output reportedly fell from 3,825MW to 39MW within an hour, TCN said NERC’s preliminary finding pointed to a lack of reactive power support — an ancillary service tied to generation-side system planning, not a transmission asset failure.

The company did acknowledge fault in a separate incident on 23 January 2026, when a busbar failure at its Sapele transmission station triggered a total system collapse, though it noted the failure was ultimately traced to a generator-connected protective device.

TCN said it does not dispute that Nigeria’s power sector is under strain or that transmission infrastructure needs continued investment. But it maintains that characterising the sector’s shortfall as primarily a transmission “wheeling” problem is not supported by the regulator’s own quarterly data, and it has called on industry commentators to anchor public claims in NERC’s published figures going forward.