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

Maryland's Newest Casino Takes a Creative Approach to Power

Learn about how a new CHP system installed at Baltimore's Horseshoe Casino uses captured heat from the engine's jacket water and exhaust systems to more than double energy efficiency.

Check out these highlights during Power Generation Week

More than 22,000 industry professionals from around the world gathered in Orlando for Power Generation Week, where innovative and cost-effective solutions for maintaining, operating and building new power generation were shared. More than 1,400 exhibiting companies from every sector of the industry showcased their products and services on the exhibit floor.

Follow Power Engineering on Twitter

Latest News

Renewable Roundtable Discussion

Power Engineering Photo of the Day

Company to supply doors to Chernobyl nuclear plant site

Groupe Gorge, through its subsidiary, Baumert, won a new order to supply technical doors to t...

Siemens to maintain California natural gas-fired power plant

Siemens (NYSE: SI) was awarded a long-term service agreement for the 507-MW Blythe Energy Cen...

Nuclear capacity must double to 1200 GW by 2050, report says

The International Energy Agency (IEA) and the Organisation for Economic Cooperation and Devel...

FirstEnergy announces several leadership changes

FirstEnergy Corp. (NYSE: FE) announced several leadership changes in its utility business, ef...

Heysham 1 nuclear reactor shut down for leak

EDF Energy shut down one of two reactors at the Heysham 1 nuclear power plant in the UK.

FERC chair says EPA CO2 plan will affect infrastructure planning

The Environmental Protection Agency (EPA) Clean Power Plan will have a big impact on infrastr...

Longview Power files amended, and maybe final, reorganization plan

Longview Power LLC and its affiliates, including coal producer Mepco LLC, on Jan. 26 filed a ...

Power Engineering Current Issue

03/01/2014
Volume 118, Issue 3
1403PE-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

Power Industry Wire News

Scorpio Bulkers Inc. Announces Closing of Previously Announced Credit Facilities, Newbuilding Vessel Deliveries, and Time Charter-Out Agreement

Scorpio Bulkers Inc. Announces Closing of Previously Announced Credit Facilities, Newbu...

Vencor International Introduces First Torrefaction Machine

Vencor International Introduces First Torrefaction Machine

HII Technologies, Inc. Announces Preliminary Revenues for Fiscal 2014 and Provides Operational Update

HII Technologies, Inc. Announces Preliminary Revenues for Fiscal 2014 and Provides Oper...

X2 Biosystems Awarded U.S. Army Contract to Evaluate Field Readiness of Concussion Management System

X2 Biosystems Awarded U.S. Army Contract to Evaluate Field Readiness of Concussion Mana...

Sasol Delays Final Investment Decision for Louisiana Gas-to-Liquids Plant, an Industrial Info News Alert

Sasol Delays Final Investment Decision for Louisiana Gas-to-Liquids Plant, an Industria...

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 >>