According to NHK, Tohoku Electric, which is based in Sendai and is the fourth-largest electric utility in Japan by revenue, plans to increase its defense in depth at its nuclear plants. Specifically it intends to prepare for scenarios where both off-site and backup generator power are lost, as happened at Fukushima Daiichi.
Tohoku plans to deploy generator trucks as a source of power in case both off-site and emergency power sources fail. It also said that it will deploy backup motors for the possible breakdown of reactor cooling pumps. Tohoku will conduct training on a regular basis with scenarios that require generator trucks to restore power and fire engines to inject water into storage pools for spent nuclear fuel.
That sounds like an excellent idea. Actually, they should have a small thermal power plant, wind power, solar power and five different connections to the grid as well.
Posted by: Karl-Friedrich Lenz | March 29, 2011 at 02:28 AM
I have not seen any evidence that the grid was down at Dai-ichi. It was available at Da-ini on the 12th per TEPCO Status Report http://bit.ly/i4eCjJ. Were there photos of pylons knocked over or wires down. There are 6 circuits into Dai-ichi. The connection to units 1&2 is high on a berm, and the wires are connected, even after the Unit 1 explosion. http://bit.ly/hTn7qD
Wires on the plant site may have been damaged.
Posted by: Martin Gugino | April 04, 2011 at 02:13 PM
Could you email me if you find something that explains why they did not power the cooling pumps from the Tohoku owned grid?? Thanks.
Note the connection into the grid for units 5&6 is also fairly high up.
http://goo.gl/maps/VBlX
Posted by: Martin Gugino | April 04, 2011 at 02:27 PM