EXPLAINER: Why national power grid keeps collapsing

EXPLAINER: Why national power grid keeps collapsing

On Tuesday, the national grid collapsed for a second time in 24 hours. Eko Electricity Distribution Company (EKEDC) and the Ikeja Electricity Distribution Company (IKEDC) announced this in separate statements on X.

This recent collapse is the seventh time the national power grid has collapsed in 2024 alone.

The Transmission Company of Nigeria (TCN), through Nafisat Ali, the Independent System Operator (ISO) executive director, told a Senate committee in April that the persistent collapse of the power grid was a compounded problem of stakeholders in the power sector.

“The causes of grid collapse in Nigeria spread across all participants, from generation companies to transmission and distribution. From generation companies, there is the inadequacy of gas supply, improper coordination of plants and gas pipelines, poor generation availability,” Ali had said.

WHAT IS THE STRUCTURE OF THE POWER SECTOR?

The power sector was privatised in 2013 under the Goodluck Jonathan administration. The power distribution and the generation burden were transferred to private distribution companies (DisCos) and private generation companies (GenCos), but the Nigerian government government retained some regulatory oversight through the Nigerian Electricity Regulatory Commission (NERC).

Some of the Nigerian distribution companies include the Egbin Power Plant, Afam Power Plc, Geregu Power Plc owned by Sahara Group and KEPCOTranscorp Power Consortium and Amperion Power Limited, respectively.

On the one hand, power distribution companies (DisCos) are in charge of delivering power from the national grid to end consumers. They operate within specific geographical areas and handle metering, billing and maintenance of the local distribution network.

The TCN, on the other hand, acts as the middle man between the GenCos and DisCos. In simple terms, the GenCos generate power and supply it to the national grid managed by the TCN, while the the transmission company transmits the power from the grid to its substations, which is where it is delivered to DisCos at a lower voltage and then to homes.

GRID COLLAPSE CAN BE FOR SECURITY AND BALANCE BETWEEN POWER GENERATION AND DEMAND

Habu Sadeik, a power sector analyst, told FIJ that grid collapse in Nigeria is mostly a tussle between electricity supply by the GenCos and demand by the DisCos, which is mostly mediated by the TCN through the grid.

Sadeik explained that the TCN has three departments which are the Transmission Service Provider (TSP), System Operator (SO) and Market Operator (MO).

“TSPs are the ones in charge of maintaining the cables and towers that transmit the light. MOs are the ones that handle market processes, rules, enforcement, finances etc. SOs are the ones in charge of maintaining and stabilising our national grid. The national grid is the interconnection of high transmission wires and cables across the country,” Sadeik explained.

“The national grid stabilisation and maintenance is done by two methods: grid frequency and voltage. The most common item that causes the national grid collapse is measured by grid frequency.

“Grid frequency measures the demand and supply of electricity dispatch to consumers from the GenCos. Frequency meters are measured in hertz (Hz). Based on the grid code, our normal frequency level is supposed to be 50Hz.

“For example, if power generation is 4000MWh and people use all the 4000MWh, then supply is equal to demand, and frequency should be 50Hz. This is a perfect condition but very unlikely.

“If we generate 4000MWh and people use 3700MWh, then supply is higher than demand, and for that reason, the frequency will show you 51Hz.

“If we generate 4000MWh and people are trying to use 4200MWh, demand is higher than supply, and for that reason, the frequency will show 49Hz.”

He explained that a simple scenario of power demand more than supply can be likened to using a small generating set to power two hotplates, an air conditioner and a microwave oven.

Like the generator set, the power grid will shut down automatically to protect itself.

“That’s how it happens, too, on the national grid. Nigeria’s national grid is set to operate on a designated frequency level upper limit of 51.25Hz, lower limit of 48.75Hz. The job of an SO is to make sure that the frequency movement is in between these two levels,” Sadeik explained.

Written by Akinjide Adebowale from Foundation For Investigative Journalism

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