Report: Tsunami, not earthquake, caused nuclear disaster at Fukushima

The March 11 earthquake was not a major factor in the accident at the Fukushima Daiichi nuclear plant in Japan, according to a report from the Fukushima Nuclear Accident Investigation Commission. The commission found that the tsunami was the “direct cause” of the disaster.

After the magnitude 9.0 earthquake struck, a safe emergency shutdown was achieved and control rods were fully inserted within seconds, and all 13 diesel generators started as per design. Cooling systems and instrumentation were working correctly.

Shaking recorded at the site was around the maximum that the plant was designed to handle and still maintain nuclear safety but walk-down checks by plant staff showed no indication of significant damage to coolantsystems, the report said.

However, tsunami waves inundated the plant with up to 9 meters (29 ft) of water, which flooded six of the generators and ruined the supporting equipment of another six within an hour of the earthquake, the report said. The remaining unit was used alternately to maintain essential systems at units 5 and 6, using only one of three power distribution panels. Some 36 other distribution panels were rendered useless by the water, according to the report.

The lack of emergency power and the inability to restore it eventually led to the loss of four reactor units and a release of radioactivity.

The report was based in part on analysis of observable factors at the site - such as high-water marks and physical damage - in addition to reams of hard data produced by reactor control systems up to the time they lost power.

The commission is comprised of experts independent of plant owner Tokyo Electric Power Co.

Subscribe to Nuclear Power International magazine

Sponsored by FLSmidth

Related Articles

Mitsubishi Heavy Industries natural gas cogeneration engine Japan

MHI to jointly develop natural gas cogeneration system

Mitsubishi Heavy Industries and Toho Gas Co. Ltd. will jointly develop a new 450 kW natural gas cogeneration system for the Japanese market.

Maryland PSC to take a little longer with review of revamped Mattawoman project

So the parties have extra time to look over some new project details, the Maryland Public Service Commission has pushed back by a couple of months its deadline for deciding on a 2013 application for the gas-fired Mattawoman Energy LLC project.

Follow Power Engineering on Twitter
Latest News

IKEA: Rooftop solar project for Kansas facility reaches operation

IKEA's rooftop solar system atop the recently opened facility in Merriam, Kansas is now opera...

Maxim Power breaches financial covenants; sounds 'going concern' warning

Maxim Power Corp. (TSX:MXG) said in a May 5 financial report that as of March 31, it has brea...

Delays at Vogtle, V.C. Summer still not threatening nuclear PTC

Southern (NYSE:SO) and SCANA (NYSE:SCG) have received bad news from their team of contractors...

Kearsarge Energy announces operation of largest SREC II solar project in Massachusetts

Kearsarge Energy, a renewable energy project developer and financier, announced the operation...

Constellation to construct 5.1 MW solar project for Community College of Baltimore County

Constellation, a subsidiary of Exelon Corp. (NYSE: EXC), announced the start of construction ...

More people near coal ash pits told not to drink their water

North Carolina officials are warning more residents living near Duke Energy's coal ash pits t...

Duke seeks delay in suit over North Carolina coal ash spill

A Delaware judge is considering Duke Energy's request for a six-month halt of a shareholder l...

Kansas Senate advances bill on state response to EPA rule

A bill approved by the Kansas Senate would require legislators to sign off on the state's pla...

Power Engineering Current Issue

02/01/2015
Volume 119, Issue 2
1502PE-cover
Products Showcase
Dynamic Fluoride Ion cleaning DFIC of industrial natural gas turbines Hi-Tech Furnace Systems

Dynamic Fluoride Ion Cleaning of IGT Parts

The Dynamic Fluoride Ion Cleaning (DFIC) Process from Hi-Tech Furnace Systems is able to clean deep, narrow cracks of oxides by cycling between negative, atmospheric, and positive pressure.

Archived Articles

2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015

Power Industry Wire News

ACWA Honors David Breninger With Lifetime Achievement Award

ACWA Honors David Breninger With Lifetime Achievement Award

ENSERVCO to Present at the 9th Annual Barrington Research Spring Investment Conference

ENSERVCO to Present at the 9th Annual Barrington Research Spring Investment Conference

Enbridge Energy Management, L.L.C. Confirms Amount of Share Distribution for First Quarter 2015

Enbridge Energy Management, L.L.C. Confirms Amount of Share Distribution for First Quar...

Venstar's New Surveyor LCP500 Load Control Panel Controls up to 10 Lighting Zones and Supports Daylight Harvesting for Significant Reductions in Energy Costs

Venstar's New Surveyor LCP500 Load Control Panel Controls up to 10 Lighting Zones and S...

XsunX Identifies Vast Growth Potential in Community Solar Market

XsunX Identifies Vast Growth Potential in Community Solar Market

Power Engineering

Article Archives for Power Engineering Magazine

Continuing Education

Professional Development Hours

To access a course listing associated to a specific topic listed below, click on the topic of choice from the list below.

Latest Energy Jobs

View more Job Listings >>