OREANDA-NEWS. August 17, 2010. During the night from August 7 to 8, a severe storm inflicted a substantial damage on the electricity transmission system, controlled by LITGRID – the Lithuanian transmission system operator (330-110 kilovolt, kV), and disturbed the operation of the transmission system.

”The most severe level of the storm was logged from 2:56 AM to to 3:15 AM in Kaunas region. The outage of hydro units of Kruonis PSP, resulting from a fault in 330 kV busbars of the power plant, threatened the stability of the Lithuanian energy system. However, thanks to swift actions of dispatch officers at Lietuvos Elektrine power plant in Elektrenai, the system was kept stable” - said Mr. Daivis Virbickas, Technical Director of LITGRID.

At the outset of the storm 11 transformers were disconnected at 11 transformer substations (TS), a voltage transformer blew up at one TS due to the voltage surge. According to D. Virbickas, the operation of six transformers was restored by the dispatch center of LITGRID within the shortest time possible. The dispatch officers with more than 20 years of work experience in the transmission system for the first time faced such severe conditions of work. However, their fast and professional work did not allow spreading of the outage.

On Sunday morning five 110 kV transformer substations were still without voltage: Zasma, Islauzas, Matuizos, Piliuona ir Rumsiskes. By now electricity supply has been restored to four TS, the remaining TS - Piliuona - will have the power supply restored by today’s afternoon.

The electricity grid of Kaunas region suffered most – six 110 kV electricity lines were damaged (among which are power lines outgoing from Kaunas HPP and Kruonis PSP). In Alytus region two 110 kV and one 330 kV voltage power lines were damaged.

Currently, four 110 kV and one 330 kV electricity transmission lines remain disconnected for repair. At 330 kV line – one support pole was pulled down (near Butrimonys village), at 110 kV lines – seven support poles broken, lines were torn and trees fell down in a number of places. Due to the nature of the damage the said lines will require a longer time for repair. However, this does not have any influence on electricity supply to customers of distribution network: electricity will be supplied to substations via alternative lines.

According to D. Virbickas, due to weather changes, caused by summer heat, in August alone a record number of outages within the transmission grid was registered – 75. This is well over 3 times more than average indicators of multi-year practice, and similar increasing statistics are logged in neighboring Latvian and Estonian electricity systems. The dispatch center of LITGRID worked rapidly and ensured a continuous reliability of electricity supply in high-voltage electricity transmission grid.

LITGRID is the electricity transmission system operator of Lithuania, controlling the flows of energy, essential for Lithuanian economy and households.  The main function of LITGRID is to ensure an effective, reliable and stable operation of Lithuanian electricity system. LITGRID is a member of ENTSO-E – the organization, uniting European electricity transmission operators and actively participates in the association’s activities.