Higashidori Nuclear Power Plant
Encyclopedia
The is a nuclear power plant
located in the town of Higashidōri
in eastern Aomori Prefecture
, on the Shimokita Peninsula
, facing the Pacific Ocean
. It is unique in Japan in that at this four-unit site, two units are run by one company, the Tōhoku Electric Power Company
and two units are run by the Tokyo Electric Power Company. The reactors are all of Toshiba
design.
Construction of Tohoku Electric's Higashidori Unit-1 began in November 2000 and was completed in December 2005. The design was based on Tohoku Electric's Onagawa Nuclear Power Plant
Unit-3, with improvements to the reactor vessel
to allow for greater ease in inspection and maintenance. A separate building, apart from the containment structure, is dedicated specifically for the heat exchanger
system based on seawater to provide primary coolant for the reactor.
, the April 7th aftershock caused the loss of all external power and the plant had to switch to backup power to supply cooling to the spent fuel pool where the reactor's fuel rods were being stored.
On 24 October 2011 a research group under professor Mitsuhisa Watanabe of the University of Toyo
published a report that raised questions about the seismic safety of the plant-site. A number of faults are present under the complex and in this study it is unclear whether these faults might be active, as some experts noted recently in the NISA
safety-screening process. In the study, the researchers said that certain characteristics are typicaal for the existence of active faults under the plant site, when they analyzed the surveys conducted by the two utilities for constructing the reactors there. Tohoku Electric and TEPCO, denied that there were active faults, and said that the faults were shaped by the swelling of water-bearing strata. Professor emeritus from the University of Hiroshima
University, who took part in the analysis, criticized the utilities for this denial. The new report might have an affect on the decision whether to resume operations of the reactor, and could also affect the earthquake-proof safety screenings of other nuclear plants.
Nuclear power plant
A nuclear power plant is a thermal power station in which the heat source is one or more nuclear reactors. As in a conventional thermal power station the heat is used to generate steam which drives a steam turbine connected to a generator which produces electricity.Nuclear power plants are usually...
located in the town of Higashidōri
Higashidori, Aomori
is a village located in northeastern Aomori Prefecture in the Tōhoku region of Japan. As of 2009, the village had an estimated population of 7,544 and a density of 25.6 persons per km²...
in eastern Aomori Prefecture
Aomori Prefecture
is a prefecture of Japan located in the Tōhoku Region. The capital is the city of Aomori.- History :Until the Meiji Restoration, the area of Aomori prefecture was known as Mutsu Province....
, on the Shimokita Peninsula
Shimokita Peninsula
The Shimokita Peninsula is the remote northeastern cape of the Japanese island of Honshū, stretching out towards Hokkaidō. Administratively the area is a part of Aomori Prefecture....
, facing the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
. It is unique in Japan in that at this four-unit site, two units are run by one company, the Tōhoku Electric Power Company
Tohoku Electric Power Company
is electric utility, servicing 7.6 million individual & corporate customers in 6 prefectures in Tōhoku region plus Niigata Prefecture. It provides electricity at 100 V, 50 Hz, though some area use 60 Hz....
and two units are run by the Tokyo Electric Power Company. The reactors are all of Toshiba
Toshiba
is a multinational electronics and electrical equipment corporation headquartered in Tokyo, Japan. It is a diversified manufacturer and marketer of electrical products, spanning information & communications equipment and systems, Internet-based solutions and services, electronic components and...
design.
Construction of Tohoku Electric's Higashidori Unit-1 began in November 2000 and was completed in December 2005. The design was based on Tohoku Electric's Onagawa Nuclear Power Plant
Onagawa Nuclear Power Plant
The is a nuclear power plant located on a 1,730,000 m2 site in Onagawa in the Oshika District and Ishinomaki city, Miyagi Prefecture, Japan. It is managed by the Tohoku Electric Power Company...
Unit-3, with improvements to the reactor vessel
Reactor vessel
In a nuclear power plant, the reactor vessel is a pressure vessel containing the Nuclear reactor coolant and reactor core.Not all power reactors have a reactor vessel. Power reactors are generally classified by the type of coolant rather than by the configuration of the reactor vessel used to...
to allow for greater ease in inspection and maintenance. A separate building, apart from the containment structure, is dedicated specifically for the heat exchanger
Heat exchanger
A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The media may be separated by a solid wall, so that they never mix, or they may be in direct contact...
system based on seawater to provide primary coolant for the reactor.
Reactors Run by Tohoku Electric Company
The Unit 1 was commissioned on March 9, 2005, and then began commercial operation on December 12, 2005. The site area is 3,580,000 m2 (885 acres).| Unit | Type | First Criticality | Electric Power |
|---|---|---|---|
| Higashidori - 1 | BWR Boiling water reactor The boiling water reactor is a type of light water nuclear reactor used for the generation of electrical power. It is the second most common type of electricity-generating nuclear reactor after the pressurized water reactor , also a type of light water nuclear reactor... |
March 9, 2005 | 1100 MW |
| Higashidori - 2 (planned) | ABWR Advanced Boiling Water Reactor The Advanced Boiling Water Reactor is a Generation III boiling water reactor. The ABWR is currently offered by GE Hitachi Nuclear Energy and Toshiba... |
Construction started 2010 | 1385 MW |
Reactors run by Tokyo Electric Company
Tepco began construction of its Higashidori-1 unit on January 25, 2011, after approval by METI. The total are of the site is 4,500,000 m2 (1,112 acres).| Unit | Type | First Criticality | Electric Power |
|---|---|---|---|
| Higashidori - 1 (planned) | ABWR Advanced Boiling Water Reactor The Advanced Boiling Water Reactor is a Generation III boiling water reactor. The ABWR is currently offered by GE Hitachi Nuclear Energy and Toshiba... |
scheduled for completion in March 2017 | 1385 MW |
| Higashidori - 2 (planned) | ABWR Advanced Boiling Water Reactor The Advanced Boiling Water Reactor is a Generation III boiling water reactor. The ABWR is currently offered by GE Hitachi Nuclear Energy and Toshiba... |
scheduled for completion in 2019 | 1385 MW |
Incidents
Although the plant was in maintenance shutdown during the 2011 Tohoku earthquake and tsunami2011 Tōhoku earthquake and tsunami
The 2011 earthquake off the Pacific coast of Tohoku, also known as the 2011 Tohoku earthquake, or the Great East Japan Earthquake, was a magnitude 9.0 undersea megathrust earthquake off the coast of Japan that occurred at 14:46 JST on Friday, 11 March 2011, with the epicenter approximately east...
, the April 7th aftershock caused the loss of all external power and the plant had to switch to backup power to supply cooling to the spent fuel pool where the reactor's fuel rods were being stored.
On 24 October 2011 a research group under professor Mitsuhisa Watanabe of the University of Toyo
Toyo
TOYO may refer to:Places:*Tōyō, Kōchi, a town in Japan*Tōyo, Ehime, a former city in Japan*Toyo Province, a Japanese province divided in 683*Toyo, Democratic Republic of the CongoCorporations:*Toyo Engineering Corporation, Japan...
published a report that raised questions about the seismic safety of the plant-site. A number of faults are present under the complex and in this study it is unclear whether these faults might be active, as some experts noted recently in the NISA
NISA
NISA may refer to:*Nuclear and Industrial Safety Agency, part of the Japanese Ministry of Economy, Trade and Industry*NIS America, the US subsidiary of Nippon Ichi Software...
safety-screening process. In the study, the researchers said that certain characteristics are typicaal for the existence of active faults under the plant site, when they analyzed the surveys conducted by the two utilities for constructing the reactors there. Tohoku Electric and TEPCO, denied that there were active faults, and said that the faults were shaped by the swelling of water-bearing strata. Professor emeritus from the University of Hiroshima
Hiroshima
is the capital of Hiroshima Prefecture, and the largest city in the Chūgoku region of western Honshu, the largest island of Japan. It became best known as the first city in history to be destroyed by a nuclear weapon when the United States Army Air Forces dropped an atomic bomb on it at 8:15 A.M...
University, who took part in the analysis, criticized the utilities for this denial. The new report might have an affect on the decision whether to resume operations of the reactor, and could also affect the earthquake-proof safety screenings of other nuclear plants.