Taiwan reactor offline after typhoon

16 July 2013

UPDATE 1: 17 July: Additional information on the shutdown sequence from the AEC
Typhoon Soulik has left Taipower's Chinshan 2 offline and in need of repair as the utility works to restore power to all parts of Taiwan, most of which suffered blackouts during the storm.

Reaching land on late on 13 July, the tropical storm caused widespread damage to the power grid, resulting in over one million homes being affected by blackouts. In accordance with regulation, Taipower reduced the output of its six nuclear power reactors to 30% and began load-shedding as winds above 117 kilometres per hour threatened transmission systems.

Chinshan 460x249
Chinshan 1 and 2

On the northern tip of the island, the height of the storm saw damage in Chinshan 2's switchyard. The Atomic Energy Council (AEC) told World Nuclear News that one suspension ground line failed and hit transmission lines, triggering automatic trips of the generator and turbines although the reactor continued operating. Later a large amount of debris washed into the seawater intake, clogging it, damaging three debris screens and prompting operators to shut the unit down completely. An additional complication came during the power-down process, the AEC told WNN, as operators failed to control feedwater properly and the reactor shut itself down automatically on a high neutron detection.

There was no damage to equipment within the buildings containing the reactor system or turbine generator set. Taipower must however repair the storm damage to the satisfaction of the Atomic Energy Council before being given permission to restart. This is expected on 17 July.

The storm had no adverse effects on Chinshan 1 or on Taiwan's four other nuclear reactors at Kuosheng and Maanshan. Live generation data from Taipower's website confirmed these are all in normal operation today.

Falling trees took down hundreds of power lines, and in the afternoon of 14 July Taipower counted some 1.1 million homes affected by blackouts. A force of 2000 engineers was fielded to make repairs and yesterday Taipower said the electrical system was 99.7% restored, although 3800 homes are still without power.

Researched and written
by World Nuclear News