Why?
"We cannot say whether it was due to lack of proper maintenance, or natural causes or due to ageing," CEB chairman E Edirisinghe told reporters at a hastily called media briefing where he tendered an apology to the utilities' customers.
"We are not ruling out any possibility. A full inquiry will be conducted in the future."
The first failure had occurred at 1.30 am on Friday and the entire system tripped. In recent years the entire system had shown a tendency to trip, but engineers had managed to restore the system within about three hours in the past.
"After the first total blackout we started restoring the supply," says CEB general manager Badra Jayaweera.
"But there was a problem of a circuit breaker at the Kotmale power station. We could not energize that circuit breaker."
Engineers had started restoring the system without bringing power from the Kotmale and Victoria system in the Mahaweli River and bringing power via a transmission line from Laxapana in the Kelani River power complex.
The transmission line running from Kotmale to Biyagama in the capital has two circuits.
"The second time we managed to restore the supply through one circuit from Kotmale to Biyagama," says Jayaweera.
"Again that was not that successful. The system was not stable and it tripped again."
The grid failed for the third time at 9.15 am, after being restored by around 8.30 am leaving only a part of the island's south with power.
Finally power was restored with both circuits in Kotmale-Biyagama line being energized.
Worst Failure
Edirisinghe says the failure was the worst in the utility's history.
"Nothing like this has happened before. The CEB is completing 60 years next month but nothing like this has happened before," says Edirisinghe
"We will have to take steps to prevent such occurrences in the future."
However major cascading outages at CEB are not very infrequent. On 13 April, 2008 there was a nation wide blackout. On January 21, 2008 a cascading outage hit grid leaving only the Mahaweli complex up. Barely two months earlier on December 07, 2007 there was another blackout.
The CEB was profitable up to the mid-1990s, with hydro plants built with foreign concessionary aid.
The utility is now suffering losses due to politicians meddling in pricing to win votes. Last year, a revised tariff plan was blunted by a court decision.
Until 2005, politicians prevented the building of cheap coal plants listed in its long term generation plan to win votes.
Expensive diesel plants had been built instead and it even uses gas turbines - the most expensive source of power - for base load at times.
Despite repeated political interference, and the pushing of expensive plants outside the long-term generation plan by powerful interests, the CEB's management provided power to an estimated 85 percent of the population.
Since 2001 it has avoided systematic 'load shedding' or power cuts. Now supply to commercial customers is perhaps the most expensive in the region. But expensive power is better for an economy than no power at all through power cuts.
Costs
Caught between expensive plants and political interference in pricing CEB now faces difficult questions about whether maintenance and stability of the system has been compromised due to other priorities and whether more investments are needed to reduce the risk of cascading outages.
Edirisinghe says there is "no additional cost" to the utility from the failure with its own maintenance division fixing the faults on "normal shift work."
In a profitably run privately-owned organization, revenue losses result in losses of profits, but in a bizarre reversal of normal economic norms, a loss making state-run monopoly's denial of service could actually reduce losses.
It is not known what the cost to the economy is from the failure. But a trade unionist attached to CEB questioned who would be held accountable for "melted ice cream" and "rotting chicken" in the freezers at tens of thousands of retail shops island-wide.
While politicians have made gains from vetoing tariff increases or coal plants, consumers who think they 'benefit' from 'cheap' electricity may not realize the true 'costs' of low quality power.
The chronic unreliability of Sri Lanka's power supply (especially power cuts up to 2002) has forced most large businesses to buy generators, avoiding major disruptions to economic growth from power failures.
Increasingly generators are also being fitted at residential houses.
Updated
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