Transformer explosion in Zell am Ziller

18.05.2006Wien

Blackout in Austria just avoided - emergency start of storage power plants and lines currently under revision kept electricity grid stable.

This morning at 11:28 a failure occurred at the transformer station Zell am Ziller belonging to VERBUND-Austrian Power Grid AG (APG), resulting in the breakdown of a 220/380 kV transformer that links the eastern to the western high-voltage grid of APG.

The cause of the failure was an explosion in the transformer’s load switch. The breakdown of the high-voltage transformer led to an extremely critical situation in the grid that could only be dealt with by taking such emergency measures that included the emergency start of the storage power stations Malta in Carinthia and by immediately hooking up the lines currently under revision. By instantly initiating the appropriate emergency measures there were no noticeable interruptions in the electricity supply for electricity users.

The explosion caused a small amount of oil to be sprayed into the immediate surroundings. The oil from the oil equalisation vessel could be fully contained in the oil drain pan as intended. The incident was immediately reported to the authorities and as an initial measure an oil-bonding agent was used to contain the sprayed oil.

Already tomorrow, Friday 19 May 2006, the installation of a substitute transformer will be started on site. This measure is expected to take a few days.