Can An Overload Cause A Nationwide Blackout, According to CS Chirchir?

Specifically, the transmission line which is designed to carry 80 megawatts was under pressure from 149 megawatts which resulted in an overload causing the blackout.

Can An Overload Cause A Nationwide Blackout, According to CS Chirchir?
A Kenya Power engineer at work on a transformer. /FILE

Energy and Petroleum Cabinet Secretary (CS) Davis Chirchir stated on Monday, December 11 that a transmission overload along the Kisumu-Muhoroni line in the western part of Kenya contributed to Sunday's nationwide blackout that plunged millions of homes into darkness.

Speaking to the media, the CS termed it a shame the latest power blackout which occurred twice in one night, bringing to four the total number of power blackouts Kenya has witnessed this year alone.

Specifically, the transmission line which is designed to carry 80 megawatts was under pressure from 149 megawatts which resulted in an overload causing the blackout.

“As a country, we are ashamed of the power blackout problem that happened yesterday. It was caused by an overload that was witnessed along the Kisumu -Muhuroni line which only carries 80 megawatts. Yesterday the line was carrying 149 Megawatts,” he said.

Energy Cabinet Secretary Davis Chirchir during a past address. /FILE

But does an overload lead to a power blackout and moreso, a nationwide blackout? Viral Tea explains below:

Overload Overview

An overload in an electrical system can potentially cause a power blackout. It occurs when the demand for electrical current in a circuit exceeds its capacity.

This can happen if too many devices are connected to a single circuit or if there is a malfunction in the electrical system.

When an overload occurs, the electrical components, such as wires and transformers, may overheat. In extreme cases, this can lead to damage or failure of the equipment and, in turn, may cause a power outage.

To prevent such overloads and potential blackouts, electrical systems are designed with safety features such as circuit breakers or fuses.

These devices are meant to interrupt the flow of electricity when an overload is detected, protecting the system from damage and reducing the risk of a blackout.

Overload vs Nationwide Blackout

While overloads in specific localized areas can lead to power outages, nationwide blackouts are typically caused by more complex and widespread issues, meaning CS Chirchir's sentiments on what caused the recent nationwide blackout may be inaccurate.

Overloads in individual circuits or regions can be isolated and managed by local protective devices, such as circuit breakers, to prevent damage and limit the impact on the broader electrical grid.

Blackout at JKIA on December 10, 2023. /X

However, nationwide blackouts are often the result of larger and more systemic problems, such as:

  1. Major Equipment Failures: Failures in critical components of the power grid, such as large transformers or transmission lines, can have cascading effects and lead to widespread outages.

  2. Natural Disasters: Severe weather events, earthquakes, hurricanes, or other natural disasters can damage infrastructure, causing extensive and simultaneous failures across the grid.

  3. Cyberattacks: Sophisticated cyberattacks targeting the control systems of power grids can disrupt operations and lead to large-scale outages.

  4. Fuel Supply Disruptions: In some cases, power generation relies on specific fuel sources (like natural gas, coal, or nuclear fuel). Disruptions in the supply chain for these fuels can impact power generation and lead to widespread outages.

While individual overloads may contribute to localized outages, a nationwide blackout typically involves a combination of factors that affect the overall stability and functionality of the power grid on a much larger scale.

Grid operators and utilities employ various measures and redundancies to minimize the risk of widespread blackouts and to quickly restore power in the event of an outage.

Load Shedding

CS Chirchir also indicated that the Ministry is considering introducing load-shedding on major power lines as a temporary mitigation measure to avoid overloads.

Load shedding is a deliberate and temporary reduction in electric power to prevent the failure of the entire power system when the electricity demand exceeds the available supply. It is a controlled and systematic way to balance the electricity demand with the available capacity in the power grid.

During periods of high demand or when there is a shortage of electricity generation capacity, grid operators may implement load shedding to avoid overloading the system. The process involves strategically cutting off the power supply to certain areas or consumers for short periods.

By doing so, the overall demand on the power grid is reduced to match the available supply, helping to maintain the stability and reliability of the electrical system.

Load shedding is a measure of last resort and is typically used when other methods of balancing the supply and demand for electricity are insufficient. It is often implemented during peak demand hours or emergencies such as equipment failures, extreme weather conditions, or fuel shortages.

While load shedding helps prevent widespread blackouts and protects the integrity of the power grid, it can be inconvenient for affected consumers as they experience temporary power outages. Many utility companies and grid operators communicate load-shedding schedules in advance to minimize disruptions and allow consumers to plan accordingly.

In this case, Chirchir explained that the load shedding will make it possible for the construction of the Narok-Bomet alternative line as well as the completion of the Sondu-Ndhiwa line to avoid overloads on the major Kisumu-Muhuroni power line.

“Construction of the Narok-Bomet 132kV and completion of Sondu -Ndhiwa power lines will de-load Kisumu -Muhuroni Chemosit power line to provide stability in South Nyanza and Central Rift regions,” he said.

Chirchir who spearheads the Energy Ministry has been criticised for failing to come up with measures to reduce the frequent power blackouts which cripple businesses in the immediate term, with Kenyans calling upon him to take responsibility for the situation.

Image of a power blackout in Nairobi. /STANDARD DIGITAL