In the course of trying to get more information on problems at Kashiwazaki-Kariwa, where TEPCO is reporting a valve problem today, I found a summary from Reuters on the operational status of all of Japan’s nuclear reactors. Thirty-two of Japan’s 54 reactors are offline today. That’s 59 per cent. Of the outages, 13 are categorized as “Unplanned.” (The other 19 are out for planned maintenance.)
In addition to the units at Fukushima Daiichi which were shut due to the March earthquake and tsunami, all four of the Fukushima Daini reactors are still closed.
All three reactors at Onagawa are still closed, presumably from earthquake damage. One reactor at the Shika facility and one at Tsuruga are also in unplanned outages dating to the earthquake.
(Note: The Reuters list includes two outages that have been planned but not yet accomplished: Tsuruga 2 and Sendai 1, which will close for maintenance over the next few days. Tsuruga has a coolant leak and Sendai is closing for scheduled maintenance.)
Here’s link to the Reuters article: http://www.reuters.com/article/2011/05/06/nuclear-japan-status-idUSL3E7G61IV20110506