Everyone has a generator story. You buy a “5kVA” generator because that is what the label says. Then you plug in the fridge, the iron and the fan at the same time, and it chokes. The label told you what the machine was built for. It did not tell you what you could actually get out of it on a bad day.
Nigeria’s power plants are the same. When you hear that the country has more than 13,000 MW of generation capacity, it is natural to ask why the lights are still off. The answer starts with a distinction that headlines often blur: installed capacity is what a plant is built to produce, but available capacity is what it can actually produce today. And between available and delivered, there is a third number again.
Three numbers that are often confused
Installed capacity
The nameplate rating of the 28 grid-connected plants: 13,625 MW.
Available capacity
What those plants declare they can actually dispatch at a given time. The ratio of the two is the Plant Availability Factor (PAF).
Generated output
What is actually sent onto the grid. Its ratio to available capacity is the load factor.
Source: NERC Q1 2026 report. Bars are drawn to scale against installed capacity.
What the 2026 data show
| Period | Average available (MW) | PAF | Average generated |
|---|---|---|---|
| January 2026 | 4,901 | 36% | about 4,421 MWh/h |
| Q1 2026 | 4,457.96 | 32.72% | 4,112.72 MWh/h |
| April 2026 | 4,286 | 31% | 4,048 MWh/h |
| September 2026 | 5,038 | about 37% | 4,089 MW |
September PAF is GridIQ’s calculation (5,038 ÷ 13,625). Average hourly generation in MWh/h is numerically the same as average output in MW. Available capacity fell by 942.42 MW between Q4 2025 and Q1 2026, from 5,400.38 MW to 4,457.96 MW.
Put simply, in the first quarter of 2026 roughly two-thirds of installed capacity was not available at any given time. The September figure of 5,038 MW is better, but it still means that around 63% of the fleet was out of reach.
Where the missing megawatts go
The gap is not one problem. It is several, and plants fail in different ways.
Fuel
Most grid plants burn gas. When gas does not arrive, or suppliers cut off indebted plants, availability falls regardless of the condition of the machines.
In February 2026, NISO said thermal plants were getting less than 43% of the gas they needed. See our outage explainer.
Plant condition
Ageing units, overdue maintenance and forced outages take capacity out of service. In April 2026, Olorunsogo 2 had just 33 MW available from 750 MW installed, and Sapele Steam had 5 MW from 720 MW and generated nothing for the month.
Water
Hydro plants such as Kainji, Jebba, Shiroro and Zungeru depend on reservoir levels and seasons, so their output moves through the year. In September 2026, Zungeru 1 declared 587 MW available but generated 358 MW.
The grid itself
Plants can only produce what the system can safely absorb. In Q1 2026, the average lower and upper daily grid frequency were 49.11Hz and 50.72Hz, both outside the prescribed band of 49.75Hz to 50.25Hz.
The outcome is concentrated. In April 2026, ten of the 28 plants produced 81% of the electricity, including Egbin, Kainji, Jebba and Ihovbor 2. The same fleet contains plants in very different shape:
Capacity available as a share of installed capacity
Source: NERC operational factsheet and quarterly data for April 2026.
A system with no cushion
There is a second lesson in the numbers. The load factor in Q1 2026 was 92.26%, meaning almost everything the plants declared available was used.
In September the load factor eased to 81%: available capacity rose 5.89% on August while generation slipped 0.30%. The highest generation ever delivered to the grid is 5,801.84 MW, recorded on 4 March 2025, which is less than half of installed capacity.
How to read the data like an analyst
- Ask which of the three numbers is being quoted. Installed, available and generated are not interchangeable.
- Watch PAF to see whether plants are healthy, and load factor to see whether the grid has headroom.
- Look at the plant, not only the fleet. A handful of plants carry most of the load.
- Remember the figure is self-reported. The capacity declared available is reported to the system operator, so trends over several months are more reliable than any single day.
The GridIQ Take
Installed capacity tells you what Nigeria has built. Available capacity tells you what Nigeria can actually use.
Closing the distance between the two, through reliable fuel, maintained plants and a stable grid, is a cheaper route to more power than building much more on paper.
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