The execution of a crucial pre-commissioning test on the Karuma Hydropower Dam plunged Uganda into a nationwide electricity blackout on Friday, causing widespread panic.
The test, aimed at confirming the readiness of the dam's turbines for operation, inadvertently led to several hours of power outage across the country.
On Friday morning, the Uganda Electricity Generation Company Ltd (UEGCL) conducted a load rejection test to assess the health and operational fitness of all six turbines at the Karuma Hydropower Dam.
The test was intended to validate the construction and installation work ahead of the dam’s technical commissioning. However, this critical assessment resulted in an unexpected and extensive power outage.
At around 12:20 PM, the Uganda Electricity Transmission Company Limited (UETCL), the state-run power grid operator, took to its X (formerly Twitter) account to explain the cause of the blackout.
"UETCL informs the general public that a national (power) blackout has been registered this morning following a load rejection test at Karuma Hydropower Plant. System restoration is underway by our technical team; all inconveniences are highly regretted," read the statement.
Despite the blackout, UEGCL expressed satisfaction with the power generated during the test, describing it as a significant milestone and a step closer to commencing full operations at the dam. UEGCL highlighted that on May 30, engineers successfully synchronized all six turbines with the national grid, completing essential capacity tests.
Following the blackout, debates arose on social media regarding the potential catastrophic impact on the national electricity infrastructure. The blackout, which lasted several hours, was attributed to the limited size of Uganda's electricity grid and its low overall consumption.
Mr. Edgar Kansiime, UEGCL's acting communication and corporate affairs manager, explained that during the test, other power plants were asked to reduce their output to accommodate the 600MW from Karuma. This adjustment created a scenario where the grid, lacking sufficient megawatts, could not sustain stability, leading to the blackout.
He noted that Uganda's grid, being relatively small and not fully developed, struggled to manage the abrupt withdrawal of 600MW, causing a significant frequency disturbance.
Kansiime further explained that in countries with larger and more robust grids, such tests typically do not result in nationwide blackouts. He stressed that the stability of an electricity grid is closely tied to its consumption size; larger grids with higher consumption levels are generally more stable.
The load rejection test is a standard procedure designed to ensure that an electricity generation plant can handle the sudden loss of load and return to normal operation without adverse effects.
The test involves abruptly switching off the load while the turbines are running at maximum capacity to check their resilience and stability. This ensures that the plant can operate safely and effectively under real-world conditions.
Despite the blackout, UEGCL emphasized the importance of the test in verifying the plant's readiness for operation. UETCL acknowledged the anticipated interruption and had issued prior warnings to the public about the potential impact of the Karuma tests through radio announcements and messages from Umeme, the power distributor.
This test at Karuma, with each of its six units rated at 100MW, was the most significant load rejection test ever conducted in Uganda, surpassing previous tests at other major plants.
The successful execution of these tests marks a crucial step towards the full operationalization of the Karuma Hydropower Dam, promising to enhance Uganda's electricity generation capacity substantially.
