May 31, Colombo (LNW): Sri Lanka’s electricity system operator has called on households and businesses with rooftop solar installations to temporarily switch off their systems today between 8:00 a.m. and 3:00 p.m. as part of efforts to safeguard the stability of the national power network.
The appeal follows a major disruption to the electricity grid on 30 May, which left thousands of consumers across several parts of the country, including Colombo and its suburbs, without power for extended periods.
According to the National System Operator (NSO), the incident was triggered by an unusual mismatch between electricity supply and demand during the Vesak holiday period. With many commercial activities scaled down and overall power consumption significantly lower than normal, the grid was faced with an exceptionally high contribution from rooftop solar systems during daylight hours.
Energy officials explained that maintaining a balance between electricity generation and consumption is essential for the secure operation of the network. The unexpected surplus of solar-generated power created operational challenges that required immediate intervention to avoid wider system instability.
As a precautionary measure, solar power users were requested to voluntarily suspend generation during peak sunlight hours. In addition, authorities temporarily isolated several 33kV distribution feeders in areas where solar penetration was particularly high in order to reduce excess power flowing into the grid.
The combined actions helped restore balance to the system, allowing engineers to gradually reconnect affected areas and return the network to normal operation. Power supply was fully reinstated by mid-afternoon on Saturday.
The NSO has thanked solar energy producers for their cooperation and stressed that the temporary request is intended solely to ensure the reliability of the national electricity supply while demand remains unusually low during the holiday period.