Do you need a website for your business?
The Principal Partner and Chief Executive Officer, Abe Lee Engineering Company Limited and former CEO, Ikeja Electric, Mr. Abiodun Ajifowobaje, tells ’FEMI ASU the causes of load rejection by electricity distribution firms and how to address the problem
Some distribution companies are said to be rejecting electricity load despite the poor supply to households and businesses. Why is this so?
Several reasons have been adduced for load rejection by the Discos in Nigeria. Like any other issue in Nigeria, the Nigerian electricity supply industry operators are more interested in passing the buck than identifying the root causes of load rejection and proffering solutions.
What in your view are the major reasons for load rejection by the Discos?
There are three main reasons for a Disco not to pick its full allocated load: transmission bottleneck; distribution bottleneck; and economic consideration.
The Transmission Company of Nigeria is the greatest contributor to load rejection in Nigeria. With an installed capacity of about 7,000 megawatts, the TCN can only wheel about 4,000MW on a continuous basis. Anything above that can only be wheeled for a limited period due to grossly overloaded equipment and lack of flexibility in evacuation. This results in giving a Disco above or below what is its rightful allocation from the grid.
Because of lack of flexibility in channelling available power in some transmission stations to needy Discos’ injection substations, such power is considered stranded or may be allocated to another Disco.
This is more pronounced during thunderstorms or bad weather. A Disco with 30No 33KV feeders for example, may lose 10No to the storm. The power lost may not be readily available to the remaining 23No 33KV feeders because the transmission station that is supplying the 10No feeders has no flexible way of transferring the stranded power to the other needy feeders. This scenario contributes greatly to national system shutdown, otherwise known as system collapse.
As with the TCN, the equipment in use by the Discos is also overloaded and in most cases obsolete. The Discos presently have no load distribution monitoring systems that will allow them to distribute available power equitably.
As a result of a small disturbance in the system therefore, due to equipment breakdown or weather-related activities, the Discos find it hard to redirect the lost power to needy areas of their network.
Perhaps the greatest challenge facing the Discos in power distribution is that all the distribution networks are radial, from the injection substation to the LT overhead lines. Rerouting lost power becomes a big issue.
As of today, most of the Discos get between 35 per cent and 40 per cent of their revenues from the industrial customers that in most cases consist of less than one per cent of the customer base. To protect this revenue source, this group of customers is first considered in load allocation from the one they get from the grid. This is a worldwide practice. It reduces commercial and collection losses.
However, some Discos, in other to reduce these losses from other group of customers, limit the power that goes to these areas, especially where commercial activities/collections are unnecessarily resisted by the customers. And if there is available power from the TCN for these areas, the load becomes a rejection when the Disco intentionally limits the power that goes to the areas.
There are 11 electricity distribution companies across the country; how is load allocated to them?
Load is allocated based on the demand of a Disco if there is enough generation and associated transmission capacity to deliver the load to the Disco. On the other hand, load is allocated/shared to the Discos based on available power generated, wheeling capability of the TCN and Discos’ maximum demand/installed load, when the generation cannot meet the national demand.
The second scenario is the case in Nigeria where generation is far below the demand. As of today, Nigeria has not been able to scientifically determine its power demand but it is true that not one Disco can get enough power from the grid to meet even 50 per cent of its demand.
The third case is a tariff-enforced load allocation. Under the Multi-Year Tariff Order structure, a Disco is allocated a percentage of the available load and this is structured into the tariff mechanism. So, by definition, load rejection is where a Disco cannot pick its allocated load despite the fact the load allocated to it is less than its demand or requirement.
How can the problem of load rejection be addressed in the sector?
We need immediate investment in the TCN network and Disco’s core asset modernisation.
With the expected 6,000MW from the NIPP power stations, generation will peak at over 10,000MW (gas availability allowing), and with transmission issues not resolved, 50 per cent of this power will be stranded and won’t get to the Discos.
If the government is not ready to privatise the TCN, then concerted efforts must be put into bringing in investors under a build, run and transfer agreement. Presently, the major issue the Discos are facing is metering of customers. While this is very important to the survival of the companies and improving customer satisfaction, this must go hand in hand with the network improvement.
With a lot of overloaded and obsolete equipment, Discos must commence technical audit and asset mapping of its core assets to enable them to prepare a very robust network expansion, maintenance and fault clearing programmes. This will reduce unnecessary breakdown and downtime.