The Public Utilities Commission of Sri Lanka (PUCSL) has approved rotating one-hour power cuts across the island for three evenings, from Monday (19 October) to Wednesday (21 October).

The country has been divided into four groups, and each group faces a one-hour interruption daily during the evening peak, between 4.30 p.m. and about 8.00 p.m. The PUCSL said the interruption and restoration times may vary by up to 30 minutes, depending on demand, available generation and weather.

On Monday, Group 1 is scheduled to lose power from between 4.30 p.m. and 5.00 p.m., Group 2 between 5.30 p.m. and 6.00 p.m., Group 3 between 6.30 p.m. and 7.00 p.m., and Group 4 between 7.30 p.m. and 8.00 p.m. The order rotates each day: on Tuesday Group 4 goes first, followed by Groups 1, 2 and 3, and on Wednesday Group 3 goes first, followed by Groups 4, 1 and 2.

The schedules say the cuts will be implemented only if the Ceylon Electricity Board (CEB) needs to manage demand because of insufficient generation capacity, following the unavailability of the Lakvijaya Power Station after a blackout.

National System Operator (NSO) Chief Executive Officer Buddhika Samarasinghe told a press conference earlier on Monday that the NSO had asked the PUCSL for approval. The NSO said peak evening demand is projected at 2,800 MW, while available supply is only 2,500 MW, leaving a shortfall of about 300 MW.

Background

The Lakvijaya Power Station, at Norochcholai in the Puttalam District, is a coal-fired plant and the largest single source of electricity on the national grid. When it goes offline, the system loses a large share of its base-load supply, and the evening hours, when household demand is at its highest, are the hardest to cover.

The NSO is the company responsible for running the national power system, including balancing supply and demand in real time. Scheduled load shedding of this kind requires regulatory approval from the PUCSL, which is why the NSO applied before the cuts began. The CEB then publishes the zone-by-zone timetable.

Rotating the order each day means that no group loses power at the same hour on consecutive days, and the burden of the evening peak is shared across the four groups.

What it means

Households and businesses should expect one interruption of about an hour each evening until Wednesday, with the exact hour depending on which group their area falls in. Because timings can shift by up to 30 minutes, people who rely on electricity in the evening, such as shops, small eateries and families with school-going children preparing for the week, may wish to plan around the published window rather than the exact start time.

The authorities have linked the cuts to the loss of the Lakvijaya plant, so the length of the programme will depend on how quickly that generation capacity returns. Residents can check the CEB and PUCSL notices for any change to the schedule.