The Ceylon Electricity Board (CEB) today issued a clarification informing the public about the results of a comprehensive investigation conducted by an independent Expert Committee regarding the nationwide power outage that occurred on February 09, 2025. 

The complete committee report is available on the website of the Public Utilities Commission of Sri Lanka (PUCSL) for public viewing, it said.

The Expert Committee has confirmed that the primary reason for this blackout was low system stability, technically known as low “system inertia,” caused by an exceptionally high contribution of solar photovoltaic (PV) power at the time. On that day, solar power supplied more than half of the country’s electricity needs, the CEB said.

According to the investigation, the blackout began with a disturbance at the 33kV Panadura Grid Substation, causing a sudden voltage drop across the entire electricity network. This incident occurred during a low-demand weekend, commonly known as the “Sunny Sunday” effect, when many businesses and industries consume less electricity, it said. 

With a high amount of solar power generation, the grid lacked sufficient inertia—normally provided by traditional power plants—to absorb the shock from the disturbance. This situation quickly led to a serious imbalance between electricity generation and demand, triggering cascading failures and ultimately the complete islandwide blackout, the statement said.

The investigation highlighted that traditional power stations, which typically maintain stability by providing inertia, were operating minimally due to the large solar generation share. To prevent future outages and enhance grid reliability, the Committee recommends urgent implementation of measures outlined in the Long-Term Generation Expansion Plan (LTGEP) and the Long-Term Transmission Plan. 

These measures include deploying Battery Energy Storage Systems (BESS), synchronous condensers, and adapting conventional generators to operate as synchronous condensers, it said.

Additionally, the Committee strongly advises including real-time inertia indicators on the grid’s control systems (mimic boards) to improve proactive management and prevent similar incidents in the future.

Importantly, the findings of this Expert Committee fully match the details provided by the CEB in its initial media statement released on February 18, 2025. “Thus, we categorically dismiss recent false claims alleging the blackout was due to a defect at Victoria Power Station or that CEB misreported the outage’s cause. Such claims are entirely baseless and contradicted by the committee’s evidence-based findings,” the CEB added.

The CEB said it remains fully committed to delivering reliable electricity services and maintaining transparent communication with the public.

“We sincerely thank all stakeholders for their cooperation and understanding as we take prompt action to strengthen the stability and resilience of Sri Lanka’s electricity network,” it further said.