The Nigerian Independent System Operator, NISO, has blamed the ongoing drop in power generation on the national grid on shortages of gas for thermal power plants. It also blames lower output from hydroelectric stations. The shortfall matters because electricity shortages are being felt widely across the country, leaving homes and businesses with fewer hours of supply.
What NISO said about the generation shortfall
The explanation came in a statement NISO released on Thursday, as the shortages were being felt across the country.
NISO stated that the restricted gas supply has stopped the affected thermal stations from running at the levels they can deliver. Smaller water inflows into reservoirs have also cut the generating capacity of hydroelectric stations.
The two causes affect different parts of the generating fleet. Thermal power plants need a steady flow of gas to run. When gas supply is restricted, the machines cannot be driven to the levels they can deliver. Hydroelectric stations depend on water held in reservoirs. When inflows are smaller, the capacity they can offer to the grid falls. Both groups of stations feed the same national grid. So a shortfall in each at the same time adds up to a visible drop in the electricity available.
Why gas and water shortages cut national grid output
Two causes sit behind the fall in generation, according to the operator:
- Gas supply: restricted supply to thermal power plants has stopped them running at the levels they can deliver.
- Water inflows: smaller inflows into reservoirs have reduced the generating capacity of hydroelectric stations.
It is worth being clear about what the statement does and does not say. NISO blames the fall in generation on restricted gas supply and on lower hydroelectric output. The plants affected are described as unable to run at the levels they can deliver. This points to a gap between what the stations could produce and what they are actually producing. That gap is the shortfall the operator is describing. It exists because of limits on fuel and water, not because the stations are unable to operate at all.
How the shortfall reaches consumers
The organisation added that the fall in available generation has cut the amount of electricity allocated to Distribution Companies, DisCos, which pass it on to consumers.
The chain from the power station to the household has several links. Generation is fed into the grid. NISO allocates the available electricity to the Distribution Companies, and the DisCos then pass it on to consumers. When available generation falls, the amount allocated to the DisCos falls with it. Customers, whether in homes or businesses, are therefore at the end of a chain in which a cut at the start is passed down at every step.
The outcome is fewer hours of supply and more load shedding on distribution networks. How badly each is affected depends on the generation available and the allocation each individual DisCo receives.
For households, fewer hours of supply means less time with lights, fans and refrigeration running on grid power. For businesses, work that needs electricity is interrupted more often. The article notes that homes and businesses alike are feeling the shortages across the country. The impact depends on the generation available and on the allocation each individual DisCo receives. So the experience will differ from one distribution network to another. Customers served by different DisCos may see different levels of supply and load shedding, even though the same national shortfall is the cause.
NISO's response and commitments
"NISO acknowledges the impact of the current generation shortfall on electricity consumers nationwide and appreciates the concerns expressed by members of the public and other stakeholders.
"While we are actively working on the diversification of our energy mix for the national grid to ensure security of supply, NISO remains committed to maintaining grid stability, optimising the dispatch of available generation, and ensuring the secure, reliable and efficient operation of the national grid within prevailing operational constraints," NISO stated.
