How Tanzania triggered 3 power blackouts in Kenya

The electricity cut comes less than a week after the switching on of the $309.26 million high-voltage power transmission line connecting Kenya and Tanzania, which allowed for trade in electricity between the two nations.

It highlights the risk of cross-border electricity trade at a time when Kenya has increased its reliance on power imports from neighbouring countries including Ethiopia and Uganda in the wake of inadequate local generation.

The blackout was first reported a few minutes past midnight before it was temporarily re-stored and went off again at 1:28am.

Kenya Power says the electricity was fully restored in the areas where it had gone off by 7:35am with the outage the latest in a series of recurring power blackouts the country has faced over the past year.

Kenya's Energy and Petroleum Cabinet secretary, Opiyo Wandayi, told the Business Daily that the blackout was caused by “a small issue” on the high-voltage power line connecting Kenya and Tanzania.

“It was a small issue on the line between Kenya and Tanzania but it was quickly fixed and as you can see we were able to restore supply very quickly,” Mr Wandayi said without giving details.

It affected all parts of Kenya except sections of the western region and North Rift in an outage that also hit neighbouring Tanzania.

The Tanzania Electric Supply Company Limited (Tanesco) informed its customers that the nationwide blackout happened at 12.12am.

“The Tanzania Electric Supply Company informs the public about a fault that occurred in the National Grid System today, December 18, 2024, at 12:12am. This fault has resulted in power outages in regions supplied by the national grid,” said Tanesco in a statement.

Both countries were cagey to blame the other, less than a week after the nations started the transfer of power through the 510km of 400 kilovolts (kv) power lines in what is aimed at meeting the growing demand for electricity in the region and deepening integration of their economies.

Known as the “backbone interconnector”, the Kenya-Tanzania link is one of several regional projects that include links running between Kenya and Ethiopia and between Kenya, Uganda and Rwanda.

Power shortages are common across Africa and businesses often complain that poor or erratic supplies deter more investors and push up prices of local products, as many firms have to rely on costly generators when power is cut.

The Kenya Electricity Transmission Company (Ketraco)—which operates Kenya’s high-voltage lines-- said the Kenya-Tanzania link was not behind the outage.

“I can confirm that it was not the transmission line per se,” Ketraco CEO John Mativo told the Business Daily, without disclosing the trigger of the outage.

The blackout is the latest in a growing number of nationwide power outages that have hit Kenya in recent years.

The power outages, many of which have lasted for hours, have been a major disruptor of the economy.

The causes of the blackouts have varied, but the main culprit has often been constraints in the country’s ageing transmission network.

The blackout significantly reduced internet connectivity across the country, said Netblocks, a global observatory that monitors internet access.

Large power users such as manufacturers bear heavy losses due to lost productivity as well as increased costs by having to turn to temporary but expensive alternatives like generators.

According to Kenya Power, its customers experienced an average of 44.9 unplanned blackouts in the year to June 2023, underlining the rising frequency of blackouts.

The Kenya – Tanzania Interconnector project involved the construction of about 510km of High Voltage Alternating Current (HVAC) transmission line from Kenya to Tanzania, the extension of Isinya (Kenya), and Singida (Tanzania) substations as well as the construction of the Arusha substation.

On Kenya’s side, it involved the construction of 96km of 400kV transmission line from the Isinya substation to the Namanga border and the extension of the 400/220kV Isinya substation.

The Tanzanian part involved the construction of a 414km 400kV transmission line from Namanga border to Singida, construction of the 400kV Arusha substation as well as the extension of the 220/33kV Singida substation.

The 400kV line, which was built at a cost of $309.26 million, was switched on Friday, transferring electricity between the two countries for the first time.

The line is part of the Eastern Africa Electricity Highway with a transfer capacity of 2,000 megawatts. Ethiopia is targeting to export 100MW to Tanzania via Kenya using the line.

Kenya, Tanzania and Ethiopia are all part of the 13-member Eastern Africa Power Pool, a regional organisation formed in 2005 to facilitate cross-border electricity trade between the member countries.

This trading is expected to commence in March 2025. The EAPP is currently developing a market platform to enable the day-ahead electricity auctions in the region.

Interconnection of the 13 national power grid is expected to be a game changer as it will enable countries to buy cheaper electricity from wherever it is generated in the region.

However, as shown by the twin blackouts in Kenya and Tanzania, it poses such risks that trading countries need to be prepared for in order to guarantee grid stability.