By Stefanos Evripidou
BLACKOUTS WERE experienced across the island on Thursday morning after a malfunction at one power generation unit knocked out another causing a loss of nearly a third of the power supply.
According to the Electricity Authority of Cyprus (EAC), at 11.19am, Unit 4 at Dhekelia power plant and Unit 4 at the main Vassilikos power plant were put out of operation, resulting in a loss of 270MW of electricity generation. Electricity demand at the time of the malfunction was 760MW.
In turn, power cuts, shedding 250MW of load were implemented across the government-controlled areas, representing 33 per cent of total demand.
It is believed the malfunction started with the relatively new Unit 4 at Vassilikos power plant, which only returned to operation last autumn after being knocked out by the July 2011 Mari munitions blast.
EAC spokesman Costas Gavrielides told the Cyprus Mail that once there is a big disturbance in the balance between demand and supply, the emergency system automatically starts shutting down power units to protect the entire network from more serious damage.
Within milliseconds, Unit 4 at Dhekelia was also shut down, after which the underfrequency protection system kicked in. This cut power to 11,000 medium voltage feeders which supply the substations that feed low voltage electricity to households. By cutting the power link to feeders and taking them out the system, this automatically reduces allows registered demand to meet available supply, and avoid a complete shutdown of power output.
The EAC released a statement saying all efforts were underway to restore power as soon as possible across Cyprus.
By 12pm on Thursday, most of the grid was functioning normally with only 10MW shortage from the morning’s output. Normal output was expected to return shortly.
Gavrielides was unable to report what had caused the malfunction to start with, saying investigations were ongoing.