The 2011 Fukushima Nuclear Power Plant Accident

How and Why It Happened

Yotaro Hatamura, Seiji Abe, Masao Fuchigami, Naoto Kasahara, Kenji Iino

• Publisher: Woodhead Publishing
• Year: 2014
• Print ISBN:
  9780081001189
• eBook ISBN:
  9780081001325
• Topic: Technology & Engineering
• Subtopic: Mechanical Engineering
• Index: Technology & Engineering

In March 2011 the Fukushima nuclear power plant (NPP) in Japan was hit by an earthquake and subsequent tsunami which resulted in the release of significant amounts of radioactive material. The incident led to the suspension of nuclear programmes by a number of countries. This book provides a definitive account of the accident. - Outlines the main sequence of events of the 2011 Fukushima nuclear power plant accident, considers the responses of central and local government, and evaluates the response of the plant owner TEPCO - Describes and assesses the effectiveness of the evacuation process and subsequent decontamination of the site and local area - Offers recommendations for improving the safe design and operation of nuclear power plants and considers the future of the Fukushima plant and nuclear power generation in Japan

1

The Fukushima-1 nuclear power plant accident

S. Abe Kansai University, Osaka, Japan

Abstract

This chapter presents the background information needed for understanding the 2011 Fukushima-1 Nuclear Power Plant accident, namely, the nuclear power generation industry in Japan. In addition, the chapter describes the industry position of the owner of Fukushima-1, Tokyo Electric Power Company, an outline of the multiunit Fukushima-1 Nuclear Power Plant, and how the plant was prepared for nuclear emergency accidents, as well as the preparedness, embodied in their regulations, of central and local governments. The severity of the Tohoku Area Pacific Offshore Earthquake and Tsunami on March 11, 2011, was beyond what the electric company, government, and people were prepared for.

Keywords

Nuclear power generation

TEPCO

Nuclear safety regulation

Nuclear emergency response

Tohoku Area Pacific Offshore Earthquake and Tsunami

Fukushima-1 accident

1.1 Introduction

This chapter provides background information about nuclear power generation in Japan, including how the Japanese nuclear power industry is structured and the position of the owner of the plant where the accident occurred. The accident was triggered by an earthquake and tsunami that crippled the plant. This chapter also covers the earthquake and tsunami data as background for understanding the accident. Although no direct fatalities were caused by radiation from the plant accident, there were related deaths. Some, however, are hard to categorize into those caused by natural disaster or those that were a consequence of forced evacuation from radiation release by the power plant. The total fatality counts are provided.

The specific troubled plant is outlined here, as well as how Japan was prepared, or at least how it thought it was prepared, for disasters of this kind.

1.2 Energy production in Japan

1.2.1 The energy situation in Japan

Japan consists of 6852 small to large islands with an area of 378,000 km². The four main islands are Honshu, Hokkaido, Shikoku, and Kyushu. About 70% of the lands are forests and rivers, and the inhabitable area is only about 30% of the land. As of July 2013, the population was just over 127 million.

Located in the warm region of East Asia, Japan enjoys variations of the four seasons. The temperature in the capital area of Tokyo reaches an average of 27.4 °C in August, and in January it is as low as 6.1 °C (1981–2010). Electricity consumption in Japan thus reaches its peak from July to September followed by a second peak from December to January. The month of lowest electricity consumption is October, when the load is about 60% of the peak value.

The private sector of Japan is responsible for the electricity business. Deregulation in the 1990s invited independent power producers (IPPs) that sell bulk electricity to power companies and some specific corporations that sell electricity to large commercial entities; however, the primary electricity supply is managed by 10 electric power companies, each monopolizing its assigned area (Figure 1.1). These 10 companies sold about 860 TWh (tera is 10 to the 12th power) of electricity, about 40% of which was to general consumers and the remaining 60% to industry.

Figure 1.1 Japan’s 10 electric power companies and their assigned regions.

Japan relies on importing most of its fossil fuel from foreign countries. In order to secure energy sources and reduce CO₂ exhaust that causes the greenhouse effect, Japan has been actively introducing nuclear power generation since the 1970s. As a result, Japan is now the third-largest nuclear-powered country, next to the United States and France, with about 30% of its electrical power generated by over 50 nuclear power plants (NPPs) (before the Fukushima accident). Figure 1.2 shows those NPPs that are referenced in this book and a fossil fuel plant, Haramachi, that suffered damage. Tokyo Electric Power Company (TEPCO) owned Fukushima-1 (Fukushima Daiichi) NPP, where the accident occurred.

Figure 1.2 Power plants discussed in this book. Prefectures are shown in italic, while power plants (with operator in parentheses) are shown within boxes. Haramachi FFPP is a fossil fuel power plant. Three prefectures, Iwate, Miyagi, and Fukushima, are shown in an expanded view in Figure 1.3 with the city of Kazo in Saitama prefecture.

1.2.2 The Fukushima-1 accident: an unprecedented nuclear power accident

On March 11, 2011, a series of tsunami caused by the Tohoku Area Pacific Offshore Earthquake destroyed all the off-site and almost all the internal power sources in Fukushima-1. These losses led to a failure to cool the reactors and the spent fuel storage pools and eventually to a Level 7 major accident on the International Nuclear and Radiological Event Scale (INES). Fukushima-2 (Fukushima-Daini) NPP was also damaged and experienced a Level 3 serious incident.

The Three Mile Island accident (Level 5) in 1979 and Chernobyl accident (Level 7) in 1986 were both single-reactor accidents; in contrast, Fukushima-1 involved, for the first time worldwide, damage to three reactors at the same time. The accident forced a large number of local residents to evacuate the area. The number of evacuees, including those from the earthquake and tsunami, reached, at its peak, over 90,000 to other prefectures and over 60,000 within the Fukushima prefecture.

The number of disaster-related deaths in Fukushima prefecture also shows the severity of the Fukushima-1 NPP accident. The term disaster-related death has a distinct definition in that the death was caused not directly by an earthquake or tsunami but by a later indirect event, and the bereaved family has received condolence money in ac...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of authors
• Woodhead Publishing Series in Energy
• Introduction
• 1. The Fukushima-1 nuclear power plant accident
• 2. The Fukushima nuclear power plant accident: the main sequence of events
• 3. The response of central and local government agencies to the Fukushima nuclear power plant accident
• 4. The response of the plant owner/operator (TEPCO) to the Fukushima nuclear power plant accident
• 5. Evacuation and decontamination in response to the Fukushima nuclear power plant accident
• 6. Learning from the Fukushima nuclear power plant accident
• 7. The future of nuclear power generation after the Fukushima accident
• Postscript
• Index