What happens during load shedding and countries that practise it

Load shedding is the deliberate, controlled shutdown of electric power in parts of a power-distribution system. It is a last-resort measure implemented by a national power supplier to prevent the collapse of the entire electricity grid.

While a blackout is an uncontrolled power failure, load shedding is not an accidental breakdown in the electricity supply. Load shedding is a planned intervention to manage a crisis where the demand for electricity is greater than the available supply.

To protect the system's integrity, the power supplier intentionally 'sheds' the excess 'load' (demand) by cutting supply to different areas on a rotating basis.

What happens during load shedding?

When load shedding is active, the power supplier switches off power to different areas according to a pre-determined schedule. These are often called 'rolling blackouts' because the outages 'roll' through various neighbourhoods.

Power suppliers, such as South Africa's Eskom, often use a 'stage' system.

A higher stage, for example Stage 6, means more power must be shed from the grid, resulting in longer and more frequent outages for all customers.

Why load shedding occurs

Load shedding is a symptom of a gap between a country's energy demand and its supply.

The causes vary but typically include:

• Failure in generation of power: Ageing, poorly maintained power plants (often coal-fired) that break down frequently.

• Fuel shortages: Lack of coal for thermal plants or, critically for regions like Southern Africa, low water levels in reservoirs like Lake Kariba, which cripples hydroelectric power generation.

• Grid instability: An outdated or fragile transmission grid that cannot handle the power load.

• Economic factors: A lack of national investment in new generation capacity over many years, or a supplier's financial inability to pay for fuel or perform adequate maintenance.

Countries that practice load shedding

Load shedding can be implemented by any country during a severe, short-term power crisis. However, several countries are known for experiencing chronic, long-term, and systemic load shedding:

• Years of load shedding in South Africa

This is the most prominent global example. The state power supplier, Eskom, has implemented rotational load shedding for over 15 years.

The system is highly structured, with published schedules from Stage 1 to Stage 8 that dictate the severity of the outages.

The primary cause is the failure of its aging and poorly maintained fleet of coal-fired power stations, which cannot meet the country's total energy demand.

• Nigeria's generator-powered homes

Nigeria's power challenge is a mix of insufficient generation, a fragile transmission grid, and gas supply issues.

While the Transmission Company of Nigeria (TCN) does engage in load shedding to manage the shortfall, the situation is often compounded by frequent, uncontrolled entire grid collapses.

This means power cuts are less predictable than in South Africa and remain a primary obstacle to economic development for its over 220 million people.

• Zambia and Zimbabwe

Both nations are heavily reliant on the Kariba Dam for hydroelectric power and crippling droughts have lowered water levels in the reservoir, severely reducing the energy output for both countries.

Their respective power suppliers, ZESCO (Zambia) and ZESA (Zimbabwe), are forced to implement severe, multi-hour daily load shedding to ration the limited electricity and prevent exhausting the dam's capacity.

• Pakistan

Pakistan has a long history of managing energy shortfalls through load shedding.

The crisis is driven by two main factors: a generation gap during peak summer months and a severe 'circular debt,' where massive unpaid bills and subsidies prevent power companies from paying for fuel.

This forces the government to schedule outages to manage both the financial and electrical deficits.

• Lebanon

This represents an extreme case where a severe economic crisis decimates the state power sector.

The state supplier, Électricité du Liban (EDL), often provides only one or two hours of electricity per day.

This is less a policy of load shedding and more a near-total collapse of the state grid.

The population is forced to rely on a parallel, expensive, and unregulated market of private diesel generators.

Kenyan outages vs. Load shedding

While Kenyans are familiar with power outages from faults or maintenance, the situation has changed. Systemic load shedding is now a reality.

In November 2025, President William Ruto stated that Kenya's electricity demand has outstripped its generation capacity of approximately 2,300 megawatts.

The president stated that this shortfall forces Kenya Power to implement load shedding, particularly during the 5:00 p.m. to 10:00 p.m. hours, to prevent grid instability.