The entire country was Tuesday hit by a crippling power blackout that lasted at least four hours following a breakdown at the country’s biggest hydroelectric station.
Businesses bore the brunt of the outage that started around noon after the 225-megawatt (MW) Gitaru hydroelectric station shut down.
“At 11:30am, a loss of generation at Gitaru hydro station resulted into a major power outage that affected other sources of electricity,” Kenya Power said in a statement.
“When it failed, the whole system tripped and shut down other power plants.”
Frequent power blackouts have seen many businesses install standby generators that switch on during supply cut-offs, raising their operating costs.
Gitaru accounts for 9.6 per cent of the country’s installed 2,333 MW.
In 2012, Gitaru experienced hiccups after a transformer at one of its turbines blew up, subjecting consumers to power rationing.
Gitaru is the largest hydropower station in East Africa located at the border of Embu and Machakos counties.
The station, which is owned and operated by power producer KenGen from which Kenya Power buys electricity for onward sale to homes and businesses, is part of the Seven Forks Hydro stations on Tana River.
Others are Masinga power station (40 MW), Kamburu (94 MW), Kindaruma (72 MW) and Kiambere (168 MW).
Kenya relies on a mix of geothermal energy, hydropower, wind and thermal energy.
At 2,333 MW, hydropower accounts for the second-largest share (35.1 per cent) of Kenya’s total power. Expensive thermal power ranks first at 35.7 per cent, while geothermal energy is third at 26.8 per cent.
Hydropower is Kenya’s cheapest source at Sh3 per kilowatt hour, geothermal comes at Sh7 per unit while a unit of thermal power tops Sh18.
Thermal electricity is only connected to the national grid after supply of cheaper hydro-electric and geothermal electricity has been exhausted, often during peak demand.