Weak lines, broken transformers top glitches afflicting Nigeria’s power sector

This may only be the second part of the year, but Nigeria’s national grid has collapsed over half a dozen times, a clear evidence of the rot that denies millions of Nigerians access to regular power.

The latest collapse occurred on June 30, and consumers were first alerted by power distribution companies, keen on absolving themselves of blame, as they attribute the collapse to a fire outbreak on a 330KV transmission line reactor in Benin.

It was fire this time around, but Nigeria’s fragile grid is susceptible to collapses stemming from both inadequate or too much capacity. Nigeria’s power value chains – generation, transmission and distribution – are deeply troubled and their inadequacies are often explained as systemic collapse.

The design of Nigeria’s power sector intends for the bulk of electricity generated through power plants to be transmitted through a transformer which converts low voltage electricity to high voltage for efficient transport.

Transmission lines are meant to carry electricity over long distances to a substation transformer which converts high voltage electricity to low voltage for distribution. It is then moved through distribution lines which carry low voltage electricity to consumers’ homes and offices for powering appliances.

This normal flow is often disrupted at every turn. There is often inadequate gas supply to power the turbines which generate electricity. Pipelines that move gas from the Niger Delta to plants outside the region are often inadequate and prone to attacks by militants. Worse still, the Federal Government fixes gas prices sold to power plants, making the venture commercially unviable. Gas plants in Nigeria require at least 3 billion cubic feet per day of gas to operate at full capacity but they often get around 900 million standard cubic feet per day or about a third of what they actually require, which is grossly inadequate.

Power generation companies could produce over 12,000MW of electricity but the most they can generate is around 7,000MW due to difficulties in getting gas supply. The Federal Government has signed a power purchase agreement (PPA) with only Azura Power, the rest have no bankable PPA and could not access foreign capital. Stringent take-or-pay condition for gas supply agreements compels the power generation companies to take barely enough to keep only a third of the turbines running.

The Transmission Company of Nigeria (TCN) says the transmission lines are capable of wheeling 8,000MW but the most they do in reality is less than 5,000MW. When TCN successfully wheeled 5,375MW on February 7, it said, “This is the first time that the nation’s power grid had generated, transmitted and distributed this quantum of power which is clearly an evidence of the success of this administration’s policy on incremental power.”

Lack of funds has constrained plans to replace weak transmission lines resulting in high transmission losses. Of the three basic distribution system designs – Radial, Loop and Network – Nigeria uses the radial system which is cheapest to build, widely used in sparsely-populated areas but highly unreliable.

The radial system has only one power source for a group of customers so a power failure, short-circuit, or a downed power line would interrupt power in the entire line which must be fixed before power can be restored.

This is not the same with the loop system which loops electricity through the service area and returns to the original point since it is tied into an alternate power source. If one source of power fails, switches are thrown (automatically or manually), and power can be fed to customers from the other source.

The network systems, on the other hand, are the most complicated and are interlocking loop systems allowing a customer to be supplied from two, three, four, or more different power supplies. It is the most expensive and also the most reliable.

DisCos’ distribution infrastructure is seriously challenged as they have consistently failed to meet actual capacity of 5371MW. DisCos record high levels of technical losses on account of the age of the distribution assets, lack of maintenance and poor investment to improve the network.

“The current distribution network is no longer applicable in this modern age as many are over 70 years,” says Edward Ajagbe, a former engineer with the Power Holding Company of Nigeria (PHCN), in an article for BusinessDay.

Distribution lines often fall with fatal consequences on consumers. Abuja DisCo was ordered to pay N300 million in fines over cases of electrocution in its franchise areas and to conduct a detailed safety audit of its network to prevent further infractions.

These technical challenges complicate energy access for millions of Nigeria. According to the Power Sector Performance Report of the Presidential Task Force on Power, in September 2018, the power sector witnessed a power loss of 107,340MW (about N51.519 billion in monetary terms) due to insufficient gas supply, distribution and transmission infrastructure.

In 2018, the number of idle power plants increased from seven to 15 as a result of gas limitations, resulting in a revenue shortfall of N52.45 billion in October last year.

Ajagbe said that the skill set of engineers who manage the systems needs to be updated.

“They should begin to replan the system with the aid of global positioning system (GPS) to create a new system that is highly efficient,” he said.

Analysts say the technical issues in the power sector worsened because the current technical personnel in the DisCos are still used to the old civil service structures. They wait on customers to report faults and respond with speed a snail can relate with. Preventive maintenance is uncommon rather than frequent and broken transformers are abandoned.

 

ISAAC ANYAOGU