MaltaMedia.com

The cause of the tripping in Boiler 7 at the Marsa power station on Monday, that left the whole Maltese Islands without power, is still being investigated but it appears that a fault in the ‘control air’ system led the boiler to trip.

Enemalta explained that the control air system provides air for the boiler instrumentation, control valves and actuators and any failure results in an automatic shutdown of the boiler. The boiler was successfully restarted shortly after the trip and is currently being used on test to supply steam to internal auxiliaries in the power station.

When the boiler tripped, the 25% of the load was transferred to the Delimara power station, which at the time was unable to meet the sudden demand, resulting in a massive and fast drop in system frequency. This in turn triggered the automatic protection devices, which monitor the system in case of overload, to protect the generators in service by tripping them. This led to a total shut down of all generating plants.

At present, Enemalta has sufficient available capacity to meet the peak demand with over 60MW in reserve, the corporation said.

Electricity was lost on all the grid at around 1610 and was back all over the country at 2048.

Supply started to be restored at 16:35 at Mater Dei Hospital, Freeport, Marsascala, Tarxien, Marsa and parts of Sliema and Msida. Later electricity was restored to the rest of Malta and at 19:45, power was restored to 70% of the island. Electricity was fully restored to all areas at 20:47.

Enemalta said the new generating plant at Delimara will help to prevent similar incidents from occurring, as it will be composed of 8 small 18MW generating units which will limit the impact of a single unit trip to a small percentage of the total load. Similarly the planned interconnector will provide a source of instantaneous reserve capacity. Furthermore, the Maltese islands will no longer be an isolated system and this will result in increased security and reliability of supply.

No one was injured during this incident and Enemalta thanked all its engineers, technicians and all other employees who did their utmost to restore supply in the shortest time possible. Enemalta also apologised to the public for any inconveniences caused.

The blackout was so heavy that prompted the Minister for Finance Tonio Fenech to address the media while more than half of the country was still in the dark on Monday.

Malta is set to connect to the European energy grid in the coming years. However the new generating plant at Delimara is marred by controversy over the technology and the supplier chosen.