View source for Nuclear power in Japan

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{{Use dmy dates|date=February 2024}}[[File:Kashiwazaki-Kariwa 04780017 (8388173865).jpg|thumb|The [[Kashiwazaki-Kariwa Nuclear Power Plant]], a nuclear plant with seven units, the largest single nuclear power station in the world<ref name="mycle">[http://www.greens-efa.org/cms/topics/dokbin/206/206749.pdf The European Parliament's Greens-EFA Group – The World Nuclear Industry Status Report 2007] {{webarchive|url=https://web.archive.org/web/20080625044818/http://www.greens-efa.org/cms/topics/dokbin/206/206749.pdf |date=25 June 2008 }} p. 23.</ref>]]Nuclear power generated 5.55% of [[Japan]]'s electricity in 2023.<ref>{{cite web |title=PRIS - Country Details |url=https://pris.iaea.org/PRIS/CountryStatistics/CountryDetails.aspx?current=JP |website=pris.iaea.org |access-date=17 December 2024}}</ref>

The country's nuclear power industry was heavily influenced by the [[Fukushima accident]], caused by the [[2011 Tōhoku earthquake and tsunami]]. Before 2011, Japan was generating up to 30% of its electrical power from nuclear reactors.<ref name="wn-japan">{{cite web|title=Nuclear Power in Japan|url=https://world-nuclear.org/information-library/country-profiles/countries-g-n/japan-nuclear-power|publisher=World Nuclear Association|access-date=30 October 2024}}</ref> 
After the Fukushima accident, all reactors were shut down temporarily. {{As of|2024|11}}, of the 54 nuclear reactors present in Japan before 2011, there were 33 operable reactors but only 13 reactors in 6 power plants were actually operating.<ref name="wn-japan" /> 
A total of 24 reactors are scheduled for decommissioning or are in the process of being decommissioned.<ref name="decom2020">{{cite web |url=https://www.nippon.com/en/features/h00238/japan%E2%80%99s-nuclear-power-plants.html |title=Japan's Nuclear Power Plants |date=10 March 2020 |work=nippon.com }}</ref> 
Others are in the process of being reactivated, or are undergoing modifications aimed to improve resiliency against natural disasters; Japan's 2030 energy goals posit that at least 33 will be reactivated by a later date.<ref>{{Cite news |date=28 March 2022 |title=Most Japanese Back Nuclear for First Time Since Fukushima |language=en |work=Bloomberg.com |url=https://www.bloomberg.com/news/articles/2022-03-28/most-japanese-back-nuclear-power-for-first-time-since-fukushima |access-date=12 July 2022}}</ref>

The Fukushima accident hardened attitudes toward nuclear power. 
In June 2011, immediately after the accident, more than 80% of Japanese said they were [[anti-nuclear]] and distrusted government information on [[radiation]],<ref name="refuse2011">{{cite web |url=http://www.csmonitor.com/World/Asia-Pacific/2011/0620/Beginning-of-the-end-for-nuclear-power-in-Japan |title=Beginning of the end for nuclear power in Japan? |author1=Gavin Blair |date=20 June 2011 |work=CSMonitor }}</ref><ref name="M. V. Ramana 43">{{cite journal |url=http://bos.sagepub.com/content/67/4/43.abstract |title=Nuclear power and the public |author=M. V. Ramana |date=July 2011 |volume=67 |issue=4 |journal=Bulletin of the Atomic Scientists |page=43 |doi=10.1177/0096340211413358 |bibcode=2011BuAtS..67d..43R |s2cid=144321178 |access-date=1 July 2011 |archive-date=1 February 2016 |archive-url=https://web.archive.org/web/20160201222218/http://bos.sagepub.com/content/67/4/43.abstract |url-status=dead |url-access=subscription }}</ref><ref name="usatoday.com">{{cite web |url=https://www.usatoday.com/news/world/story/2011-09-19/japan-anti-nuclear-protest/50461872/1 |title=Thousands march against nuclear power in Tokyo |date = September 2011|work=USA Today }}</ref> but ten years later, in March 2021, only 11 percent of Japanese said they wanted that nuclear energy generation to be discontinued immediately. Another 49 percent were asking for a gradual exit from nuclear energy.<ref>{{cite web |url=https://www.jaif.or.jp/en/japanese-opinion-poll-finds-that-views-on-nuclear-power-turn-slightly-positive/
 |title=Japanese Opinion Poll Finds That Views on Nuclear Power Turn Slightly Positive
 |date=25 March 2020
|website=www.jaif.or.jp
 |url-status=live
 |archive-url=https://web.archive.org/web/20210311010624/https://www.jaif.or.jp/en/japanese-opinion-poll-finds-that-views-on-nuclear-power-turn-slightly-positive/
 |archive-date=11 March 2021 |accessdate=2 November 2021 }}</ref> 
In February 2023, a survey by [[Asahi Shimbun]] showed that 51% of participants in Japan favored the restart of nuclear plant operations, with 42% opposed.<ref name=":0" />

==History==
===Early years===
[[File:HD.15.031 (11824391473).jpg|thumb|Three experimental reactors installed in [[Tōkai, Ibaraki]], played key roles in the early development of nuclear power in Japan: from left to right, JRR-1 (1957), JRR-2 (1960), and JRR-3 (1962).]]
After the ''[[Atoms for Peace]]'' speech given by then-American President [[Dwight D. Eisenhower|Eisenhower]] at the UN General Assembly in 1953, a total ban on nuclear research, imposed during the [[Occupation of Japan|post-war occupation of Japan]] and continued after Japan regained sovereignty, was lifted. Future Prime Minister [[Yasuhiro Nakasone]] and his peers from the [[Kaishintō|Kaishintō Party]] (a forerunner to the [[Liberal Democratic Party (Japan)|Liberal Democratic Party]]) drafted a 235-million-yen budget (the amount symbolically referencing uranium-235), which was approved by the [[National Diet|Diet]].<ref>{{Cite web |date=2003-05-30 |title=［時代の証言者］戦後政治 中曽根康弘＜４＞原子力研究、予算で壁破る |url=https://www.yomiuri.co.jp/serial/jidai/20190204-OYT8T50188/ |access-date=2025-02-04 |website=読売新聞オンライン |language=ja}}</ref>

Around the same time, the [[Atomic Energy Act of 1954]] was enacted in America, and Japan received condensed uranium from the country in 1955. Two experimental reactors, JRR-1 (built by [[North American Aviation]]'s nuclear division) and JRR-2 (largely based on [[Chicago Pile-5]]), were constructed. A much more powerful experimental reactor JRR-3 was completed in 1962 by a consortium led by [[Hitachi]], the first experimental reactor to be fully designed and built in Japan.<ref>{{Cite web |title=１．JRR-1 |url=https://www.aec.go.jp/jicst/NC/about/hakusho/wp1958/sb20202.htm |access-date=2025-02-04 |website=www.aec.go.jp}}</ref> Also in 1955, Nakasone's group drafted the [[Atomic Energy Basic Law]], which was enacted in Japan to promote nuclear power while limiting activities strictly to peaceful purposes.<ref>Johnston, Eric, "[http://search.japantimes.co.jp/cgi-bin/nn20110716f1.html Key players got nuclear ball rolling]", ''[[Japan Times]]'', 16 July 2011, p. 3.</ref> The [[Japanese Atomic Energy Commission]] was established as a regulatory body, with its first chair, [[Matsutarō Shōriki]], a newspaper magnate, also being a key promoter of nuclear power in Japan.

A prototype nuclear power station, JPDR, began power generation on 26 October 1963.<ref>{{Cite web |title=JPDR - ATOMICA - |url=https://atomica.jaea.go.jp/dic/detail/dic_detail_86.html |access-date=2025-02-04 |website=atomica.jaea.go.jp}}</ref> Japan's first commercial nuclear power plant, the [[Tōkai Nuclear Power Plant]], was built using main components imported from the [[General Electric Company]] in the UK and was connected to the grid on 25 July 1966. This reactor remains the only [[Magnox]] reactor ever built on Japanese soil.<ref>{{Cite web |title=昭和３４年　原子力委員会月報４(5)日本原子力発電（株）東海発電所設置原子炉について |url=https://www.aec.go.jp/jicst/NC/about/ugoki/geppou/V04/N05/19590502V04N05.html |access-date=2025-02-04 |website=www.aec.go.jp}}</ref> In 1969, the first [[Nuclear marine propulsion|nuclear-powered ship]] in Japan (and the fourth in the world), ''[[RV Mirai#Mutsu (1972–1996)|Mutsu]]'', was launched by [[Mitsubishi Heavy Industries]] (reactor) and [[IHI Corporation|IHI]] (hull).<ref>{{Cite web |title=失敗事例 > 原子力船むつ放射線漏れ |url=https://www.shippai.org/fkd/cf/CA0000615.html |access-date=2025-02-04 |website=www.shippai.org}}</ref>

====Light water reactors====
[[File:Onagawa Nuclear Power Station in 2012.png|thumb|right|The [[Onagawa Nuclear Power Plant]], a 3-unit BWR site typical of Japan's nuclear plants.]]
[[General Electric]] offered [[Light-water reactor|light water reactors]] at a discounted price as soon as Yasuhiro Nakasone, then the Minister of Science and Technology, began revising the country's nuclear power strategy in 1961. This offer was accepted, and [[Tsuruga Nuclear Power Plant|Tsuruga-1]] was commissioned in March 1970 as Japan's first [[Boiling water reactor|BWR]].<ref>{{Cite web |title=『福井県史』通史編6　近現代二 |url=https://www.library-archives.pref.fukui.lg.jp/fukui/07/kenshi/T6/T6-4a5-02-01-03-05.htm |access-date=2025-02-04 |website=www.library-archives.pref.fukui.lg.jp}}</ref> GE teamed up with Hitachi and [[Toshiba]] to build BWRs, while [[Westinghouse Electric Corporation|Westinghouse]] collaborated with Mitsubishi Heavy Industries (MHI) to promote [[Pressurized water reactor|PWRs]]. By the late 1970s, these companies began constructing plants independently. All nuclear reactors built in Japan have been either BWRs or PWRs, with Hitachi and Toshiba (which later acquired [[Westinghouse Electric Company|Westinghouse's nuclear division]] to build PWRs as well) still responsible for the former and MHI for the latter.<ref>{{Cite web |date=2024-06-11 |title=日立・東芝の原発は「非主流」 建て替えに向け不透明感 |url=https://www.nikkei.com/article/DGXZQOUC2937P0Z20C24A5000000/ |access-date=2025-02-04 |website=日本経済新聞 |language=ja}}</ref>

Developments in nuclear power since that time have seen contributions from Japanese companies and research institutes on the same level as the other big users of nuclear power. From the early 1970s to the present, the Japanese government promoted the siting of nuclear power plants through a variety of policy instruments involving soft social control and financial incentives.<ref>[[Daniel P. Aldrich]] 'How the Japanese Government Manipulated Public Opinion'[https://newrepublic.com/article/world/85463/japan-nuclear-power-regulation]</ref>

===Later years===

Japan's nuclear industry was not hit as hard by the effects of the [[Three Mile Island accident]] (TMI) or the [[Chernobyl disaster]] as some other countries. 
Construction of new plants continued to be strong through the 1980s and 1990s.  While many new plants had been proposed, all were subsequently canceled or never brought past initial planning. 
Cancelled plant orders include:
* The Hōhoku Nuclear Power Plant at [[Hōhoku, Yamaguchi]]{{snd}}1994
* The Kushima Nuclear Power Plant at [[Kushima, Miyazaki]]{{snd}}1997
* The Ashihama Nuclear Power Plant at Ashihama, Mie{{snd}}2000 (the first Project at the site in the 1970s was completed at Hamaoka as Unit 1&2)
* The [[Maki Nuclear Power Plant]] at [[Maki, Niigata (Kambara)]]{{snd}}Canceled in 2003
* The Suzu Nuclear Power Plant at [[Suzu, Ishikawa]]{{snd}}2003

Starting in the mid-1990s there were several nuclear-related accidents and cover-ups in Japan that eroded public perception of the industry, resulting in protests and resistance to new plants. 
These accidents included the [[Tokaimura nuclear accident]], the [[Mihama Nuclear Power Plant|Mihama steam explosion]], cover-ups after an accident at the [[Monju Nuclear Power Plant|Monju reactor]], among others, more recently the [[2007 Chūetsu offshore earthquake|Chūetsu offshore earthquake]] aftermath. 
While exact details may be in dispute, it is clear that the safety culture in Japan's nuclear industry has come under greater scrutiny.<ref name="Japan cancels nuclear plant">{{cite news| url=http://news.bbc.co.uk/2/hi/asia-pacific/652169.stm | work=BBC News | title=Japan cancels nuclear plant | date=22 February 2000}} [The news fails to note that the Tokaimura accident did not happen in a power plant.]</ref>

===2000s===
[[File:Electricity production in Japan.PNG|thumb|right|Up to 2011, Japan had steadily increased its nuclear generation over time. A dip in 2003 was due to TEPCO data falsification scandals in 2002 and caused a poor operating record.]]On 18 April 2007, Japan and the United States signed the [[United States-Japan Joint Nuclear Energy Action Plan]], aimed at putting in place a framework for the joint research and development of nuclear energy technology.<ref>[https://www.energy.gov/news/4991.htm United States and Japan Sign Joint Nuclear Energy Action Plan] {{Webarchive|url=https://web.archive.org/web/20090720060428/http://www.energy.gov/news/4991.htm |date=20 July 2009 }}, ''[[United States Department of Energy]]'', published 2007-04-25, accessed 2 May 2007</ref> 
Each country will conduct research into [[fast reactor]] technology, fuel cycle technology, advanced computer simulation and modeling, small and medium reactors, safeguards and physical protection; and [[nuclear waste]] management.<ref>[https://www.energy.gov/media/USJapanFactSheet.pdf Fact Sheet: United States-Japan Joint Nuclear Energy Action Plan] {{webarchive|url=https://web.archive.org/web/20110521144837/http://www.energy.gov/media/USJapanFactSheet.pdf |date=21 May 2011 }}, ''[[United States Department of Energy]]'', published 2007-04-25, accessed 2 May 2007</ref> 
In March 2008, [[Tokyo Electric Power Company]] announced that the start of operation of four new nuclear power reactors would be postponed by one year due to the incorporation of new earthquake resistance assessments. 
Units 7 and 8 of the Fukushima Daiichi plant would now enter commercial operation in October 2014 and October 2015, respectively. 
Unit 1 of the Higashidori plant is now scheduled to begin operating in December 2015, while unit 2 will start up in 2018 at the earliest.<ref>{{cite web|url=http://www.world-nuclear-news.org/NN-New_Japanese_nuclear_power_reactors_delayed-260308.html |title=New Japanese nuclear power reactors delayed |publisher=World-nuclear-news.org |date=26 March 2008 |access-date=25 September 2013}}</ref> 
As of September 2008, Japanese ministries and agencies were seeking an increase in the 2009 budget by 6%. 
The total requested comes to 491.4 billion [[Japanese yen]] (US$4.6 billion), and the focuses of research are the development of the fast breeder reactor cycle, next-generation light water reactors, the [[Iter]] project, and seismic safety.<ref>NucNet. [http://www.worldnuclear.org/_news_database/rss_detail_features.cfm?objID=82712AE9-DDAF-4807-94A71F1B04B33B71 Japan Budget Proposals Seek Increase In Nuclear Spending] {{Webarchive|url=https://web.archive.org/web/20111004131733/http://www.worldnuclear.org/_news_database/rss_detail_features.cfm?objID=82712AE9-DDAF-4807-94A71F1B04B33B71 |date=4 October 2011 }}. 11 September 2008.</ref>

===Fukushima accident and aftermath===
[[File:Japan net electricity generation in 2000 through 2017 (48061019128).png|thumb|upright=1.2|The use of nuclear power (in yellow) in Japan declined significantly after the Fukushima accident]]
{{main|Fukushima nuclear accident}}

An energy white paper, approved by the Japanese Cabinet in October 2011, says "public confidence in the safety of nuclear power was greatly damaged" by the Fukushima accident in March 2011, and calls for a reduction in the nation's reliance on nuclear power. 
It also omits a section on nuclear power expansion that was in the previous year's policy review.<ref name="Tsuyoshi Inajima and Yuji Okada">{{cite news |url=https://www.bloomberg.com/news/2011-10-28/nuclear-promotion-dropped-in-japan-energy-policy-after-fukushima.html |title=Nuclear Promotion Dropped in Japan Energy Policy After Fukushima |author1=Tsuyoshi Inajima  |author2=Yuji Okada  |name-list-style=amp |date=28 October 2011 |work=Bloomberg }}</ref> 
Nuclear Safety Commission Chairman Haruki Madarame told a parliamentary inquiry in February 2012 that "Japan's atomic safety rules are inferior to global standards and left the country unprepared for the Fukushima nuclear disaster last March". 
There were flaws in, and lax enforcement of, the safety rules governing Japanese nuclear power companies, and this included insufficient protection against tsunamis.<ref>{{cite web |url=http://news.businessweek.com/article.asp?documentKey=1376-LZF0E16JTSEY01-3P322MREJS02KO2666B7QSBOV9 |title=Nuclear Safety Chief Says Lax Rules Led to Fukushima Crisis |date=16 February 2012 |work=Bloomberg }}{{dead link|date=April 2023|bot=medic}}{{cbignore|bot=medic}}</ref>

On 6 May 2011, Prime Minister [[Naoto Kan]] ordered the [[Hamaoka Nuclear Power Plant]] to be shut down as an earthquake of magnitude 8.0 or higher is likely to hit the area within the next thirty years.<ref name="Story">[https://www.bbc.co.uk/news/world-asia-pacific-13306358 Story] at [[BBC]] News, 6 May 2011. retrieved 8 May 2011</ref><ref name="digitaljournal.com">[http://www.digitaljournal.com/article/306399 Story] at Digital Journal. retrieved 7 May 2011</ref><ref name="bloomberg.com">[https://www.bloomberg.com/news/2011-05-07/chubu-electric-s-board-meets-on-possible-shutdown-of-nuclear-power-plant.html Story] at [https://www.bloomberg.com Bloomberg], 7 May 2011. retrieved 8 May 2011</ref><ref name="Japan nuke plant suspends work">{{cite web |url=http://www.heraldsun.com.au/ipad/japan-nuke-plant-suspends-work/story-fn6s850w-1226056070930 |title=Japan nuke plant suspends work |date=15 May 2011 |work=Herald Sun }}</ref><ref name="M. V. Ramana 44">{{cite journal |url=http://bos.sagepub.com/content/67/4/43.abstract |title=Nuclear power and the public |author=M. V. Ramana |date=July 2011 |volume=67 |issue=4 |journal=Bulletin of the Atomic Scientists |page=44 |doi=10.1177/0096340211413358 |bibcode=2011BuAtS..67d..43R |s2cid=144321178 |access-date=1 July 2011 |archive-date=1 February 2016 |archive-url=https://web.archive.org/web/20160201222218/http://bos.sagepub.com/content/67/4/43.abstract |url-status=dead |url-access=subscription }}</ref>

As of 27 March 2012, Japan had only one out of 54 nuclear reactors operating; the [[Tomari Nuclear Power Plant#Reactors on site|Tomari-3]], after the [[Kashiwazaki-Kariwa Nuclear Power Plant#Reactors|Kashiwazaki-Kariwa 6]] was shut down.<ref name="ntse">[http://www.nyteknik.se/nyheter/energi_miljo/karnkraft/article3436603.ece "Soon Japan's nuclear power stands still"] ''[[NyTeknik]]'', 27 March 2012. Retrieved 27 March 2012. {{in lang|sv}} [http://translate.google.dk/translate?sl=sv&tl=en&js=n&prev=_t&hl=da&ie=UTF-8&layout=2&eotf=1&u=http%3A%2F%2Fwww.nyteknik.se%2Fnyheter%2Fenergi_miljo%2Fkarnkraft%2Farticle3436603.ece English translation]</ref> 
The Tomari-3 was shut down for maintenance on 5 May, leaving Japan with no nuclear-derived electricity for the first time since 1970, when the country's then-only two reactors were taken offline for five days for maintenance.<ref name=Guardian>{{cite web |url=https://www.theguardian.com/world/2012/may/05/japan-shuts-down-last-nuclear-reactor |title=Japan shuts down last working nuclear reactor |author=David Batty |date= 5 May 2012 |work=The Guardian }}</ref> On 15 June 2012, approval was given to restart [[Ōi Nuclear Power Plant|Ōi Units 3 and 4]]<ref>[http://www1.kepco.co.jp/gensi/monitor/live_unten/u_real.html Real-time display] {{Webarchive|url=https://web.archive.org/web/20120618051846/http://www1.kepco.co.jp/gensi/monitor/live_unten/u_real.html |date=18 June 2012 }} Japanese – Ohi 3 and 4 are the last two on the page</ref> which could take six weeks to bring them to full operation. On 1 July 2012, unit 3 of the [[Ōi Nuclear Power Plant]] was restarted. 
This reactor can provide 1,180 [[Megawatts|MW]] of electricity.<ref>{{cite web|last=Davis |first=Will |url=http://atomicpowerreview.blogspot.com/2012/06/ohi-reactor-restart-in-japan-fully.html |title=Ohi reactor restart in Japan fully approved |publisher=Atomicpowerreview.blogspot.com |date=15 June 2012 |access-date=25 September 2013}}</ref><ref>{{cite web|url=http://www.taipeitimes.com/News/front/archives/2012/06/17/2003535527 |title=Japan approves two reactor restarts |publisher=Taipeitimes.com |date=18 September 2013 |access-date=25 September 2013}}</ref> On 21 July 2012 unit 4 was restarted, also 1,180 MW.<ref>{{cite web|url=http://zeenews.india.com/news/world/oi-nuclear-plant-s-no-4-reactor-begins-generating-power_788863.html |title=Oi nuclear plant's No 4 reactor begins generating power |date=21 July 2012 |publisher=Zeenews.india.com |access-date=25 September 2013}}</ref> 
The reactor was shut down again on 14 September 2013, again leaving Japan with no operating power reactors.<ref>Matsuyama, Kanoko.  [https://www.bloomberg.com/news/2013-09-16/shutdown-of-japan-s-last-nuclear-reactor-raises-power-concerns.html "Shutdown of Japan’s Last Nuclear Reactor Raises Power Concerns".]  [https://www.bloomberg.com/ ''Bloomberg''.]  15 September 2013.  Retrieved 5 February 2014.</ref>

[[File:Nuclear power station.svg|thumb|upright=1.2|Global status of nuclear deployment as of 2023
{| style="width: 100%; font-size: 1em;"
|-
| valign=top |
{{legend2|#3b74bc|Operating reactors, building new reactors}}
{{legend2|#5db6e9|Operating reactors, planning new build}}
{{legend2|#4a9e06|No reactors, building new reactors}}
{{legend2|#96d167|No reactors, new in planning}}
{{legend2|#d4aa00|Operating reactors, stable}}
{{legend2|#ef2929|Operating reactors, decided on phase-out}}
{{legend2|#000000|Civil nuclear power is illegal}}
{{legend2|#b9b9b9|No reactors}}
|}
]]
Government figures in the 2014 Annual Report on Energy show that Japan depended on imported fossil fuels for 88% of its electricity in fiscal year 2013, compared with 62% in fiscal 2010. Without significant nuclear power, the country was self-sufficient for just 6% of its energy demand in 2012, compared with 20% in 2010. 
The additional fuel costs to compensate for its nuclear reactors being idled was ¥3.6 trillion. 
In parallel, domestic energy users have seen a 19.4% increase in their energy bills between 2010 and 2013, while industrial users have seen their costs rise 28.4% over the same period.<ref>{{cite news |url=http://www.world-nuclear-news.org/NP-Japan-continues-to-count-cost-of-idled-reactors-1706144.html/| title=Japan continues to count cost of idled reactors |publisher=[[World Nuclear News]] |date=17 June 2014}}</ref>

In 2018 the Japanese government revised its energy plan to update the 2030 target for nuclear energy to 20%-22% of power generation by restarting reactors, compared to LNG 27%, coal 25%, renewables 23% and oil 3%.  This would reduce Japan's carbon dioxide emissions by 26% compared to 2013, and increase self-sufficiency to about 24% by 2030, compared to 8% in 2016.<ref name=wnn-20180703>{{cite news |url=http://www.world-nuclear-news.org/NP-Japanese-Cabinet-approves-new-basic-energy-plan-0307184.html |title=Japanese Cabinet approves new basic energy plan |publisher=World Nuclear News |date=3 July 2018 |access-date=9 July 2018}}</ref>

Since the Fukushima nuclear accident, Japan has restarted twelve reactors and fifteen more have applied to restart, including two that are under construction. Amid the [[Russian invasion of Ukraine]], Japan's Prime Minister announced the restart of nine units by winter 2022 and seven more by summer 2023.<ref name=":0">{{Cite web |title=Nuclear Power in Japan {{!}} Japanese Nuclear Energy - World Nuclear Association |url=https://world-nuclear.org/information-library/country-profiles/countries-g-n/japan-nuclear-power.aspx |access-date=2024-04-05 |website=world-nuclear.org}}</ref>

====Investigations on the Fukushima accident====

The [[National Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission]] (NAIIC) is the first independent investigation commission by the [[Diet of Japan|National Diet]] in the 66-year history of Japan's constitutional government. 
NAICC was established on 8 December 2011 with the mission to investigate the direct and indirect causes of the Fukushima nuclear accident. 
NAICC submitted its inquiry report to both houses on 5 July 2012.{{refn| group = lower-alpha |The [http://naiic.go.jp/en/ startpage of the Fukushima Nuclear Accident Independent Investigation Commission internetsite] stated on 10 July 2012 the following information which was used as the basis for the previous sentences: "NAIIC (The National Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission) is the first independent investigation commission by the National Diet in the 66-year history of Japan’s constitutional government. NAICC was established on 8 December 2011 with the mission to investigate the direct and indirect causes of the Fukushima nuclear incident. NAICC submitted its inquiry report to both houses on 5 July 2012."}}<ref>{{cite web|title=国会事故調 {{!}} 東京電力福島原子力発電所事故調査委員会のホームページ|url=http://naiic.o.jp/en/|publisher=National Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission|access-date=9 July 2012|author=National Diet of Japan Fukushima Nuclear Accident Independent Investigation Commission}}{{Dead link|date=April 2019 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

The 10-member commission compiled its report based on more than 1,167 interviews and 900 hours of hearings.<ref name="WP20120705W">{{cite news|last=Harlan|first=Chico|title=Report blasts Japan's preparation for, response to Fukushima disaster|url=https://www.washingtonpost.com/world/new-report-blasts-japans-preparation-for-response-to-fukushima-disaster/2012/07/05/gJQAN1OEPW_story.html|access-date=9 July 2012|newspaper=The Washington Post|date=5 July 2012}}</ref><ref name="NYT20120705">{{cite news|title=Inquiry Declares Fukushima Crisis a Man-Made Disaster|url=https://www.nytimes.com/2012/07/06/world/asia/fukushima-nuclear-crisis-a-man-made-disaster-report-says.html?_r=2|access-date=9 July 2012|newspaper=The New York Times|date=5 July 2012|author=Hiroko Tabuchi}}</ref> 
It was a six-month independent investigation, the first of its kind with wide-ranging subpoena powers in Japan's constitutional history, which held public hearings with former Prime Minister [[Naoto Kan]] and [[Tokyo Electric Power Company|Tokyo Electric Power Co]]'s former president [[Masataka Shimizu]], who gave conflicting accounts of the disaster response.<ref name="Bloomberg20120705">{{cite web|title=Fukushima nuclear accident 'man-made', not natural disaster|url=https://www.smh.com.au/world/fukushima-nuclear-accident--manmade-not-natural--disaster-20120705-21jrl.html|work=Bloomberg|date=5 July 2012|publisher=The Sydney Morning Herald|access-date=9 July 2012}}</ref> 
The commission chairman, Kiyoshi Kurokawa, declared with respect to the Fukushima nuclear incident: "It was a profoundly man-made disaster{{snd}}that could and should have been foreseen and prevented."<ref>{{cite news|title=Japan's nuclear meltdown could have been prevented|url=https://www.washingtonpost.com/opinions/japans-nuclear-meltdown-could-have-been-prevented/2012/07/05/gJQAf9nPQW_story.html|access-date=9 July 2012|newspaper=The Washington Post|date=6 July 2012|author=Editorial Board}}</ref> 
He added that the "fundamental causes" of the disaster were rooted in "the ingrained conventions of Japanese culture."<ref>{{cite web|title=Message from the Chairman|url=http://naiic.go.jp/wp-content/uploads/2012/07/NAIIC_report_lo_res2.pdf|work=Executive Summary, The official report of The Fukushima Nuclear Accident Independent Investigation Commission|publisher=NAIIC|access-date=12 July 2012|author=Kiyoshi Kurokawa|page=9|quote=What must be admitted – very painfully – is that this was a disaster "Made in Japan". Its fundamental causes are to be found in the ingrained conventions of Japanese culture: our reflexive obedience; our reluctance to question authority; our devotion to ‘sticking with the program’; our groupism; and our insularity.|archive-url=https://web.archive.org/web/20120710082826/http://naiic.go.jp/wp-content/uploads/2012/07/NAIIC_report_lo_res2.pdf|archive-date=10 July 2012|url-status=dead}}</ref> 
The report outlines errors and willful negligence at the plant before the [[2011 Tōhoku earthquake and tsunami]] on 11 March 2011 and a flawed response in the hours, days, and weeks that followed. It also offers recommendations and encourages Japan's parliament to "thoroughly debate and deliberate" the suggestions.<ref name="CNN20120705">{{cite web|title=Japanese parliament report: Fukushima nuclear crisis was 'man-made'|url=https://edition.cnn.com/2012/07/05/world/asia/japan-fukushima-report/index.html|publisher=CNN|access-date=9 July 2012|author1=Yoko Wakatsuki  |author2=Jethro Mullen |date=5 July 2012 |name-list-style=amp }}</ref>

===Post-Fukushima nuclear policy===
{{Image frame
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Japan's new energy plan, approved by the Liberal Democratic Party cabinet in April 2014, calls nuclear power "the country's most important power source".<ref>{{Cite web|url=http://en.haberler.com/japan-reverses-its-withdrawal-from-nuclear-power-418262/|title = Japan Reverses Its Withdrawal from Nuclear Power|date = 13 April 2014}}</ref> Reversing a decision by the previous Democratic Party, the government will re-open nuclear plants, aiming for "a realistic and balanced energy structure". In May 2014 the Fukui District Court blocked the restart of the Oi reactors.<ref>{{cite web |url=http://www.japantimes.co.jp/opinion/2014/05/23/commentary/reflect-on-fukui-nuclear-ruling/|title=Reflect on Fukui nuclear ruling|date=23 May 2014|work=The Japan Times}}</ref> 
In April 2015 courts blocked the restarting of two reactors at the [[Takahama Nuclear Power Plant]] but permitted the restart of two reactors at the [[Sendai Nuclear Power Plant]].<ref name=economist-20150425>{{cite news |url=https://www.economist.com/news/asia/21649557-court-cases-frustrate-efforts-restart-japans-nuclear-plants-legal-fallout |title=Nuclear power in Japan – Legal fallout |newspaper=The Economist |date=25 April 2015 |access-date=3 May 2015}}</ref> The government hopes that nuclear power will produce 20% of Japan's electricity by 2030.<ref name=economist-20150425/>

As of June 2015, approval was being sought from the new Nuclear Regulatory Agency for 24 units to restart, of the 54 pre-Fukushima units. 
The units also have to be approved by the local prefecture authorities before restarting.<ref name=nei-20150624>{{cite news |url=http://www.neimagazine.com/opinion/opinionjapan-what-is-the-future-for-nuclear-power-4608426/ |title=Japan{{snd}}what is the future for nuclear power? |author=Steve Kidd |publisher=Nuclear Engineering International |date=24 June 2015 |access-date=11 July 2015}}</ref>

In July 2015 fuel loading was completed at the [[Sendai Nuclear Power Plant|Sendai-1]] nuclear plant, it restarted 11 August 2015 and was followed by unit 2 on 1 November 2015. Japan's Nuclear Regulatory Authority approved the restart of [[Ikata Nuclear Power Plant|Ikata-3]] which took place on 19 April 2016, this reactor is the fifth to receive approval to restart.<ref>{{Cite web|url=http://www.nei.org/News-Media/News/Japan-Nuclear-Update|title = News}}</ref> The [[Takahama Nuclear Power Plant]] unit 4 restarted in May 2017 and unit 3 in June 2017. And by 2023, Unit 1 and 2 of Takahama also restarted.<ref>{{Cite web |last=IndraStra Global |first=News Team |date=12 February 2024 |title=Nuclear Reactors Restart in Japan Reduce LNG Imports for Power Generation |url=https://www.indrastra.com/2024/02/nuclear-reactors-restart-in-japan.html |access-date=19 February 2024 |website=IndraStra Global |language=en |publication-place=[[New York City]] |issn=2381-3652 |lccn=2015203560 |oclc=923297365}}</ref>

In November 2016 Japan signed a nuclear cooperation agreement [[Nuclear power in India|with India]]. 
Japanese nuclear plant builders saw this as potential lifeline given that domestic orders had ended following the Fukushima disaster, and India is proposing to build about 20 new reactors over the next decade. However, there is Japanese domestic opposition to the agreement, as India has not agreed to the [[Treaty on the Non-Proliferation of Nuclear Weapons]].<ref name=jt-20161111>{{cite news |url=https://www.nytimes.com/2016/11/12/business/international/japan-india-nuclear-deal.html |title=Japan's Nuclear Industry Finds a Lifeline in India After Foundering Elsewhere |author=Jonathan Soble |newspaper=The Japan Times |date=11 November 2016 |access-date=17 November 2016}}</ref>

In 2014, following the failure of the prototype [[Monju Nuclear Power Plant|Monju]] [[sodium-cooled fast reactor]], Japan agreed to cooperate in developing the French [[ASTRID (reactor)|ASTRID]] demonstration sodium-cooled fast breeder reactor.<ref name=bl-20140505>{{cite news |url=https://www.bloomberg.com/news/articles/2014-05-05/japan-to-work-with-france-on-future-fast-breeder-atomic-reactor |title=Japan to Work With France on Future Fast-Breeder Atomic |author=Tara Patel, Gregory Viscusi |publisher=Bloomberg |date=5 May 2014 |access-date=3 December 2016}}</ref><ref name=mainichi-20161022>{{cite news |url=http://mainichi.jp/english/articles/20161022/p2a/00m/0na/005000c |title=France wants Japan to share 570 billion yen ASTRID reactor development cost |newspaper=The Mainichi |date=22 October 2016 |access-date=3 December 2016}}</ref> As of 2016, France was seeking the full involvement of Japan in the ASTRID development.<ref name=mainichi-20161022/><ref name=asahi-20160922>{{cite news |url=http://www.asahi.com/ajw/articles/AJ201609220057.html |title=Ministries spar as Japan focuses on fast reactor project in France |newspaper=The Asahi Shimbun |date=22 September 2016 |access-date=3 December 2016}}</ref>

In 2015, the [[Agency for Natural Resources and Energy]] changed the accounting provisions of the Electricity Business Act, so companies can account for decommissioning costs in ten yearly installments rather than a one-time charge. This will encourage the decommissioning of older and smaller nuclear units, most of which have not restarted since 2011.<ref name=wnn-20190213>{{cite news |url=http://www.world-nuclear-news.org/Articles/Genkai-2-to-be-decommissioned |title=Genkai 2 to be decommissioned |publisher=World Nuclear News |date=13 February 2019 |access-date=15 February 2019}}</ref>

In 2022, during the [[2021–present global energy crisis|global energy crisis]] which greatly increased the cost of imported fossil fuels, Japan's prime minister announced the building of safer next-generation nuclear reactors and restarting idle existing plants would be considered. In 2022 ten reactors were operational producing about 5% of Japan's electricity.<ref name=guardian-20220825>{{cite news |url=https://www.theguardian.com/world/2022/aug/25/japan-eyes-return-to-nuclear-power-more-than-a-decade-after-fukushima-disaster |title=Japan eyes return to nuclear power more than a decade after Fukushima disaster |last=McCurry |first=Justin |newspaper=The Guardian |date=25 August 2022 |access-date=26 August 2022}}</ref>

In December 2022, Japan's [[Nuclear Regulation Authority]] (NRA) approved a draft-rule allowing nuclear reactors to operate beyond 60 years by excluding inspection downtimes. This was part of a policy at enhancing nuclear reactor use, including restarting many, extending older units' lives, and developing new reactor technologies. In February 2023, the cabinet approved this policy and the construction of new reactors. By May 2023, a law was enacted to officially omit shutdown periods from the 60-year limit, subject to the economy minister's approval. The law also required the NRA to perform inspections every 10 years for reactors over 30 years of operation.<ref name=":0" />

==Seismicity==
Japan has had a long [[Seismicity in Japan|history of earthquakes and seismic activity]], and destructive [[earthquake]]s, often resulting in [[tsunami]]s, occur several times a century. Due to this, concern has been expressed about the particular risks of constructing and operating nuclear power plants in Japan. [[Amory Lovins]] has said: "An earthquake-and-tsunami zone crowded with 127 million people is an unwise place for 54 reactors".<ref>{{cite web |url=https://www.huffingtonpost.com/amory-lovins/nuclear-power-fukushima-_b_837643.html |title=With Nuclear Power, 'No Acts of God Can Be Permitted'|author=Amory Lovins |date=18 March 2011 |work=Huffington Post }}</ref> To date, the most serious seismic-related accident has been the [[Fukushima Daiichi nuclear disaster]], following the [[2011 Tōhoku earthquake and tsunami]].

Professor [[Katsuhiko Ishibashi]], one of the [[Seismology|seismologists]] who have taken an active interest in the topic, coined the term ''[[genpatsu-shinsai]]'' (原発震災), from the Japanese words for "nuclear power" and "quake disaster" to express the potential worst-case catastrophe that could ensue.<ref name=why-worry>Katsuhiko Ishibashi, [http://www.japanfocus.org/-Ishibashi-Katsuhiko/2495 "Why worry? Japan's nuclear plants at grave risk from quake damage"] ''The Asia-Pacific Journal: Japan Focus'' (11 August 2007) Also published by the ''International Herald Tribune'' (11 August 2007). Retrieved 24 March 2011</ref><ref>Michael Reilly, [https://www.newscientist.com/article/mg19526144.500-insight-where-not-to-build-nuclear-power-stations.html "Insight: Where not to build nuclear power stations"] (preview only) ''[[New Scientist]]'' (28 July 2007). Retrieved 24 March 2011 {{subscription required}}</ref> Dr [[Kiyoo Mogi]], former chair of the Japanese [[Coordinating Committee for Earthquake Prediction]],<ref name="nature-07-07-25">[http://www.nature.com/nature/journal/v448/n7152/ Quake shuts world's largest nuclear plant] Nature, vol 448, 392–393, {{doi|10.1038/448392a}}, published 2007-07-25, accessed 18 March 2011</ref> has expressed similar concerns, stating in 2004 that the issue 'is a critical problem which can bring a catastrophe to Japan through a man-made disaster'.<ref name=mogi-2004>[http://www.terrapub.co.jp/journals/EPS/pdf/2004/5608/5608li.pdf Two grave issues concerning the expected Tokai Earthquake] {{Webarchive|url=https://web.archive.org/web/20170914083131/http://www.terrapub.co.jp/journals/EPS/pdf/2004/5608/5608li.pdf |date=14 September 2017 }} Kiyoo Mogi, ''Earth Planets Space'', Vol. 56 (No. 8), pp. li–lxvi, published 2004, accessed 11 March 2011</ref><ref>[https://www.science.org/doi/abs/10.1126/science.264.5166.1656 Japan Holds Firm to Shaky Science] ''Science'', Vol. 264 no. 5166 pp. 1656–1658, {{doi|10.1126/science.264.5166.1656}}, published 1994-06-17, accessed 18 March 2011</ref>

Warnings from Kunihiko Shimazaki, a professor of seismology at the University of Tokyo, were also ignored. In 2004, as a member of an influential cabinet office committee on offshore earthquakes, Mr. Shimazaki "warned that Fukushima's coast was vulnerable to tsunamis more than twice as tall as the forecasts of as much as five meters put forth by regulators and Tokyo Electric".<ref name=jap12/> Minutes of the meeting on 19 February 2004, show that the government bureaucrats running the committee moved quickly to exclude his views from the committee's final report. He said the committee did not want to force Tokyo Electric to make expensive upgrades at the plant.<ref name=jap12>{{cite web |url=http://www.power-eng.com/news/2012/03/11/warnings-on-fukushima-ignored-insiders-say-nl-they-attribute-failure-to-cozy-ties-between-government.html |title=Warnings on Fukushima ignored, insiders say; They attribute failure to cozy ties between government and industry |date=3 November 2012 |work=Power Engineering }}</ref>

[[Hidekatsu Yoshii]], a member of the [[House of Representatives of Japan|House of Representatives]] for [[Japanese Communist Party]] and an [[Anti-nuclear movement|anti-nuclear campaigner]], warned in March and October 2006 about the possibility of the severe damage that might be caused by a tsunami or earthquake.<ref name=wsj-11-03-28>{{cite news|url=https://www.wsj.com/articles/SB10001424052748703576204576226530875684182|title=Lawmaker Broached Plant Risk|author1=Dvorak, Phred |author2=Hayashi, Yuka |newspaper=The Wall Street Journal|date=28 March 2011|access-date=28 March 2011}}</ref> During a parliamentary committee in May 2010 he made similar claims, warning that the cooling systems of a Japanese nuclear plant could be destroyed by a landslide or earthquake.<ref name=wsj-11-03-28 /> In response, Yoshinobu Terasaka, head of the [[Nuclear and Industrial Safety Agency]], replied that the plants were so well designed that "such a situation is practically impossible".<ref name=wsj-11-03-28 /> Following damage at the [[Kashiwazaki-Kariwa Nuclear Power Plant]] due to the [[2007 Chūetsu offshore earthquake]], Kiyoo Mogi called for the immediate closure of the [[Hamaoka Nuclear Power Plant]],<ref name="nature-07-07-25"/><ref name=times-07-07-19>[https://web.archive.org/web/20080724145742/http://www.timesonline.co.uk/tol/news/world/asia/article2096238.ece Nuclear crisis in Japan as scientists reveal quake threat to power plants] The Times, published 2007-07-19, accessed 18 March 2011</ref> which was knowingly built close to the centre of the expected [[Tokai earthquakes|Tōkai earthquake]].<ref name=mogi-2004 /> Katsuhiko Ishibashi previously claimed, in 2004, that Hamaoka was "considered to be the most dangerous nuclear power plant in Japan".<ref name=japantimes-04-05-23>[http://search.japantimes.co.jp/cgi-bin/fl20040523x2.html Japan's deadly game of nuclear roulette] The Japan Times, published 2004-05-23, accessed 18 March 2011</ref>

The [[International Atomic Energy Agency]] (IAEA) has also expressed concern. At a meeting of the [[G8|G8's]] Nuclear Safety and Security Group, held in Tokyo in 2008, an IAEA expert warned that a strong [[earthquake]] with a [[Richter magnitude scale#Richter magnitudes|magnitude]] above {{nowrap|7.0}} could pose a 'serious problem' for Japan's nuclear power stations.<ref name=wl>{{cite web|url=http://www.physorg.com/news/2011-03-iaea-japan-nuclear-quake-wikileaks.html |title=IAEA warned Japan over nuclear quake risk: WikiLeaks |publisher=physorg.com |access-date=25 September 2013}}</ref> Before Fukushima, "14 lawsuits charging that risks had been ignored or hidden were filed in Japan, revealing a disturbing pattern in which operators underestimated or hid seismic dangers to avoid costly upgrades and keep operating. But all the lawsuits were unsuccessful".<ref>{{cite journal |url=http://bos.sagepub.com/content/67/6/44.full |title=Fukushima and the inevitability of accidents |author=Charles Perrow |date=November–December 2011 |journal=Bulletin of the Atomic Scientists |volume=67 |issue=6 |pages=44–52 |doi=10.1177/0096340211426395 |bibcode=2011BuAtS..67f..44P |s2cid=144904813 |access-date=2 November 2011 |archive-date=22 June 2016 |archive-url=https://web.archive.org/web/20160622040039/http://bos.sagepub.com/content/67/6/44.full |url-status=dead |url-access=subscription }}</ref> Underscoring the risks facing Japan, a 2012 research institute investigation has "determined there is a 70% chance of a magnitude-7 earthquake striking the Tokyo metropolitan area within the next four years, and 98% over 30 years". The March 2011 earthquake was a magnitude 9.<ref>{{cite web |url=https://www.wsj.com/articles/SB10001424052970204624204577178472176340772?mod=googlenews_wsj
 |title=Japan Reviews Disaster Plan Amid New Quake Concerns |author=Mitsuru Obe |date=24 January 2012 |work=Wall Street Journal }}</ref>

=== Design standards ===
[[File:Japan Nuclear Earthquake Shaking.PNG|thumb|upright=1.6|Horizontal acceleration experienced and design values during the 2007 and 2011 major earthquake and earthquake-tsunami events.]]
Between 2005 and 2007, three Japanese nuclear power plants were shaken by earthquakes that far exceeded the maximum [[peak ground acceleration]] used in their design.<ref name=autralian-11-03-13>[http://www.theaustralian.com.au/japans-nuclear-plant-quake-protection-too-lax-said-expert/story-fn84naht-1226020553408 Japan's nuclear plant quake protection too lax, said expert] [[The Australian]] published 2011-03-13, accessed 6 April 2011</ref> The [[tsunami]] that followed the [[2011 Tōhoku earthquake and tsunami|2011 Tōhoku earthquake]], inundating the [[Fukushima I nuclear accidents|Fukushima I Nuclear Power Plant]], was more than twice the design height,<ref>{{cite web | url=http://www.world-nuclear-news.org/RS_Fukushima_faced_14-metre_tsunami_2303113.html |title=Fukushima faced 14-metre tsunami |date=23 March 2011|publisher=World Nuclear News |access-date=24 March 2011}}</ref> while the ground acceleration also slightly exceeded the design parameters.<ref>[http://neutroneconomy.blogspot.com/2011/04/japans-earthquake-regulations.html Japan's Earthquake Regulations for Nuclear Power] ''The Neutron Economy'' published 2011-04-04, accessed 6 April 2011</ref>

In 2006 a Japanese government subcommittee<!-- probably the Subcommittee on Safety Examination Guidelines for Seismic Design--> was charged with revising the national guidelines on the earthquake-resistance of nuclear power plants, which had last been partially revised in 2001,<ref name=2006-seismic-guide>[http://www.nsc.go.jp/english/taishin.pdf Regulatory Guide for Reviewing Seismic Design of Nuclear Power Reactor Facilities] {{webarchive|url=https://web.archive.org/web/20110721224251/http://www.nsc.go.jp/english/taishin.pdf |date=21 July 2011 }} [[Japanese Nuclear Safety Commission|Nuclear Safety Commission]], published 2006-09-19, accessed 6 April 2011</ref> resulting in the publication of a new seismic guide – the 2006 ''Regulatory Guide for Reviewing Seismic Design of Nuclear Power Reactor Facilities''.<ref name=2006-seismic-guide /> The subcommittee membership included Professor Ishibashi, however his proposal that the standards for surveying active [[Fault (geology)|faults]] should be reviewed was rejected and he resigned at the final meeting, claiming that the review process was 'unscientific'<ref name="nature-07-07-25"/><ref name=businessweek-11-03-11>{{cite web |url=http://www.businessweek.com/news/2011-03-17/japan-nuclear-disaster-caps-decades-of-faked-reports-accidents.html |title=Japan Nuclear Disaster Caps Decades of Faked Reports, Accidents |author=Jason Clenfield |date=17 March 2011 |work=Bloomberg Businessweek }}{{dead link|date=April 2023|bot=medic}}{{cbignore|bot=medic}}</ref> and the outcome rigged<ref name=businessweek-11-03-11 /><ref name=bloomberg-07-12-12>[https://www.bloomberg.com/apps/news?pid=newsarchive&sid=awR8KsLlAcSo Japan Nuclear Energy Drive Compromised by Conflicts of Interest] [[Bloomberg L.P.|Bloomberg]], published 2007-12-12, accessed 11 April 2011</ref> to suit the interests of the [[Japan Electric Association]], which had 11 of its committee members on the 19-member government subcommittee.<ref name=bloomberg-07-12-12 /> Ishibashi has subsequently claimed that, although the new guide brought in the most far-reaching changes since 1978, it was 'seriously flawed' because it underestimated the [[Peak ground acceleration|design basis of earthquake ground motion]].<ref name=why-worry /> He has also claimed that the enforcement system is 'a shambles'<ref name=why-worry /><ref name=autralian-11-03-13 /> and questioned the independence of the [[Japanese Nuclear Safety Commission|Nuclear Safety Commission]] after a senior Nuclear and Industrial Safety Agency official appeared to rule out a new review of the NSC's seismic design guide in 2007.<ref name=why-worry />

Following the publication of the new 2006 Seismic Guide, the [[Nuclear and Industrial Safety Agency]], at the request of the Nuclear Safety Commission, required the design of all existing nuclear power plants to be re-evaluated.<ref>[http://www.jaif.or.jp/english/news/20070730_nsc.pdf The NSC views on, and future actions to take for, the impacts due to the Niigata-ken Chuetsu-oki Earthquake in 2007 – NSC Decision No. 17, 2007] {{Webarchive|url=https://web.archive.org/web/20111001124353/http://www.jaif.or.jp/english/news/20070730_nsc.pdf |date=1 October 2011 }} [[Japanese Nuclear Safety Commission|Nuclear Safety Commission]], published 2007-07-30, accessed 6 April 2011</ref>

=== Geological surveys ===
The standard of geological survey work in Japan is another area causing concern. In 2008 Taku Komatsubara, a [[geologist]] at the [[National Institute of Advanced Industrial Science and Technology]] alleged that the presence of active [[Fault (geology)|faults]] was deliberately ignored when surveys of potential new power plant sites were undertaken, a view supported by a former [[topography|topographer]].<ref>[http://www.upiasia.com/Security/2008/06/12/japans_nuclear_facilities_face_quake_risk/3945/ Japan's nuclear facilities face quake risk] UPI Asia, published 2008-06-12, accessed 11 April 2011</ref> Takashi Nakata, a seismologist from the [[Hiroshima Institute of Technology]] has made similar allegations and suggests that conflicts of interest between the Japanese nuclear industry and the regulators contribute to the problem.<ref name=bloomberg-07-12-12 />

A 2011 [[Natural Resources Defense Council]] report that evaluated the seismic hazard to reactors worldwide, as determined by the Global Seismic Hazard Assessment Program data, placed 35 of Japan's reactors in the group of 48 reactors worldwide in very high and high seismic hazard areas.<ref>{{cite conference|url=http://docs.nrdc.org/nuclear/files/nuc_11102801a.pdf |title=Global Implications of the Fukushima Disaster for Nuclear Power |conference=International Seminar on Nuclear War and Planetary Emergencies — 44th Session |author1=Thomas B. Cochran |author2=Matthew G. McKinzie |publisher=Natural Resources Defense Council |date=19 August 2011 |access-date=24 February 2012 |archive-url=https://web.archive.org/web/20120726084146/http://docs.nrdc.org/nuclear/files/nuc_11102801a.pdf |archive-date=26 July 2012 |url-status=dead }}</ref>

== Nuclear power plants ==
{{for|the details of each reactor|list of commercial nuclear reactors#Japan}}
{{main|List of nuclear power plants in Japan}}
As of January 2022 there are 33 operable reactors in Japan, of which 12 reactors are currently operating.<ref>{{Cite web|url=https://www.worldnuclearreport.org/+-Japan-37-+.html|title = Japan}}</ref> Additionally, 5 reactors have been approved for restart and further 8 have restart applications under review.

{{stack begin}}
{{geoGroup}}
{{Japan nuke plant map|float=right|width=550}}
{{stack end}}
{| class="wikitable sortable"
|-
! Station !! Operable<br/>capacity ([[Megawatt|MW]]) !! Location !! Coordinates !! Status
|-
| [[Fugen Nuclear Power Plant|Fugen]] || {{n/a}} || [[Tsuruga, Fukui|Tsuruga]], [[Fukui Prefecture|Fukui]] || {{coord|35|45|16|N|136|00|59|E|name=Fugen Nuclear Power Station}} || {{safe|Decommissioned}}
|-
| [[Fukushima Daiichi Nuclear Power Plant|Fukushima Daiichi]] || {{n/a}} || [[Ōkuma, Fukushima|Ōkuma]] and [[Futaba, Fukushima|Futaba]], [[Fukushima Prefecture|Fukushima]] || {{coord|37|25|17|N|141|01|57|E|name=Fukushima I Nuclear Power Station}} || {{eliminated|To be decommissioned}}<ref name="breakingnews.ie">[http://www.breakingnews.ie/world/fukushima-plant-to-be-decommissioned-499350.html Fukushima plant to be decommissioned] BreakingNews, published 2011-03-31, accessed 8 April 2011</ref>
|-
| [[Fukushima Daini Nuclear Power Plant|Fukushima Daini]] || 4,400 || [[Naraha, Fukushima|Naraha]] and [[Tomioka, Fukushima|Tomioka]], [[Fukushima Prefecture|Fukushima]] || {{coord|37|19|10|N|141|01|16|E|name=Fukushima II Nuclear Power Station}} || {{eliminated|To be decommissioned}}<ref name="world-nuclear-news.org">[http://www.world-nuclear-news.org/Articles/Tepco-declares-Fukushima-Daini-for-decommissioning Tepco declares Fukushima Daini for decommissioning] World Nuclear News, published 2019-07-31, accessed 23 August 2019</ref>
|-
| [[Genkai Nuclear Power Plant|Genkai]] || 2,919 || [[Higashimatsuura District, Saga|Higashimatsuura]], [[Saga Prefecture|Saga]] || {{coord|33|30|56|N|129|50|14|E|name=Genkai Nuclear Power Station}} || {{yes|Operational (units 3<ref>{{cite news|title=Seventh Japanese reactor restarted|url=http://www.world-nuclear-news.org/C-Seventh-Japanese-reactor-restarted-2303185.html|access-date=24 March 2018|work=www.world-nuclear-news.org}}</ref> and 4 only,<ref name=WNNgenkai4>{{cite news |title=Genkai unit 4 supplying power again |url=http://www.world-nuclear-news.org/C-Genkai-unit-4-supplying-power-again-1906185.html |access-date=22 June 2018 |work=www.world-nuclear-news.org}}</ref> unit 1 to be decommissioned<ref name=wnn-20170419/>)}}
|-
| [[Hamaoka Nuclear Power Plant|Hamaoka]] || 3,504 || [[Omaezaki]], [[Shizuoka Prefecture|Shizuoka]] || {{coord|34|37|25|N|138|08|33|E|name=Hamaoka Nuclear Power Station}} || {{good|Suspended (units 1 and 2 to be decommissioned)}}
|-
| [[Higashidōri Nuclear Power Plant|Higashidōri]] || 1,100 || [[Higashidōri]], [[Aomori Prefecture|Aomori]] || {{coord|41|11|17|N|141|23|25|E|name=Higashidōri Nuclear Power Station}} || {{good|Suspended}}
|-
| [[Ikata Nuclear Power Plant|Ikata]] || 890 || [[Nishiuwa District, Ehime|Nishiuwa]], [[Ehime Prefecture|Ehime]] || {{coord|33|29|27|N|132|18|41|E|name=Ikata Nuclear Power Station}} || {{yes|Operational (unit 3 only, units 1 and 2 to be decommissioned<ref name=wnn-20170419/><ref>{{cite news|title=Shikoku decides to retire Ikata 2|url=http://www.world-nuclear-news.org/C-Shikoku-decides-to-retire-Ikata-2-2703184.html|access-date=4 May 2018|work=www.world-nuclear-news.org}}</ref>)}}
|-
| [[Kashiwazaki-Kariwa Nuclear Power Plant|Kashiwazaki-Kariwa]] || 8,212 || [[Kashiwazaki, Niigata|Kashiwazaki]] and [[Kariwa]], [[Niigata Prefecture|Niigata]] || {{coord|37|25|42|N|138|36|06|E|name=Kashiwazaki-Kariwa Nuclear Power Station}} || {{good|Suspended}}<ref>{{cite book|title=Kashiwazaki, Japan Earthquake of July 16, 2007|year=2007|publisher=ASCE Press, Technical Council on Lifeline Earthquake Engineering|location=Reston, VA|isbn=9780784410622|url=http://www.asce.org/Product.aspx?id=2147486137&productid=16377|editor=Alex K. Tang, PE and Anshel J. Schiff|url-status=dead|archive-url=https://web.archive.org/web/20130928112951/http://www.asce.org/Product.aspx?id=2147486137&productid=16377|archive-date=28 September 2013}}</ref>
|-
| [[Maki Nuclear Power Plant|Maki]] || {{n/a}} || [[Maki, Niigata (Nishikanbara)|Maki]], [[Niigata Prefecture|Niigata]] || {{coord|37|25|17|N|141|01|57|E|name=Maki Nuclear Power Station}} || {{BLACK|Withdrawn}}
|-
| [[Mihama Nuclear Power Plant|Mihama]] || 780 || [[Mihama, Fukui|Mihama]], [[Fukui Prefecture|Fukui]] || {{coord|35|42|09|N|135|57|48|E|name=Mihama Nuclear Power Station}} || {{yes|Operational (unit 3 only, units 1 and 2 to be decommissioned<ref name=wnn-20170419/>)}}
|-
| [[Monju Nuclear Power Plant|Monju]] || {{n/a}} || [[Tsuruga, Fukui|Tsuruga]], [[Fukui Prefecture|Fukui]] || {{coord|35|44|25|N|135|59|17|E|name=Monju Nuclear Power Station}} || {{eliminated|To be decommissioned}}
|-
| [[Namie-Odaka Nuclear Power Plant|Namie-Odaka]] || {{n/a}} || [[Minamisōma]] and [[Namie, Fukushima|Namie]], [[Fukushima Prefecture|Fukushima]] || {{coord|37|30|48.2|N|141|02|03.1|E|name=Namie-Odaka Nuclear Power Plant}} || {{BLACK|Withdrawn}}
|-
| [[Ōi Nuclear Power Plant|Ōi]] || 2,254 || [[Ōi, Fukui|Ōi]], [[Fukui Prefecture|Fukui]] || {{coord|35|32|26|N|135|39|07|E|name=Ōi Nuclear Power Station}} || {{yes|Operational (units 3 and 4<ref name=oi4>{{cite news|title=Ohi No.4 reactor restarted- News |url=https://www3.nhk.or.jp/nhkworld/en/news/20180509_30/|access-date=10 May 2018|work=NHK World|language=en|archive-url=https://web.archive.org/web/20180510185734/https://www3.nhk.or.jp/nhkworld/en/news/20180509_30/|archive-date=10 May 2018|url-status=dead}}</ref> only, units 1 and 2 to be decommissioned)}}
|-
| [[Ōma Nuclear Power Plant|Ōma]] || ''1,383'' || [[Ōma]], [[Aomori Prefecture|Aomori]] || {{coord|41|30|35|N|140|54|37|E|name=Ōma Nuclear Power Plant}} || {{partial|Under construction}}
|-
| [[Onagawa Nuclear Power Plant|Onagawa]] || 2,174 || [[Oshika District, Miyagi|Oshika]] and [[Ishinomaki]], [[Miyagi Prefecture|Miyagi]] || {{coord|38|24|04|N|141|29|59|E|name=Onagawa Nuclear Power Station}} || {{yes|Operational (unit 2 only, unit 1 to be decommissioned<ref>{{cite web |title=Tohoku decides to decommission oldest Onagawa unit |url=http://www.world-nuclear-news.org/Articles/Tokohu-decides-to-decommission-oldest-Onagawa-unit |website=World Nuclear News |access-date=3 December 2018}}</ref>)}}
|-
| [[Sendai Nuclear Power Plant|Sendai]] || 1,780 || [[Satsumasendai, Kagoshima|Satsumasendai]], [[Kagoshima Prefecture|Kagoshima]] || {{coord|31|50|01|N|130|11|23|E|name=Sendai Nuclear Power Station}} || {{yes|Operational}} (units 1 and 2)
|-
| [[Shika Nuclear Power Plant|Shika]] || 1,898 || [[Shika, Ishikawa|Shika]], [[Ishikawa Prefecture|Ishikawa]] || {{coord|37|03|40|N|136|43|35|E|name=Shika Nuclear Power Station}} || {{good|Suspended}}
|-
| [[Shimane Nuclear Power Plant|Shimane]] || 820 || [[Matsue]], [[Shimane Prefecture|Shimane]] || {{coord|35|32|18|N|132|59|57|E|name=Shimane Nuclear Power Station}} || {{good|Suspended (unit 1 to be decommissioned<ref name=wnn-20170419/>)}}
|-
| [[Takahama Nuclear Power Plant|Takahama]] || 3,304 || [[Takahama, Fukui|Takahama]], [[Fukui Prefecture|Fukui]] || {{coord|35|31|20|N|135|30|17|E|name=Takahama Nuclear Power Station}} || {{yes|Operational}} (units 1, 2, 3 and 4)
|-
| [[Tōkai Nuclear Power Plant|Tōkai]] || 1,100 || [[Tōkai, Ibaraki|Tōkai]], [[Ibaraki Prefecture|Ibaraki]] || {{coord|36|27|59|N|140|36|24|E|name=Tōkai Nuclear Power Station}} || {{good|Suspended}}
|-
| [[Tomari Nuclear Power Plant|Tomari]] || 2,070 || [[Tomari, Hokkaido|Tomari]], [[Hokkaido]] || {{coord|43|02|10|N|140|30|45|E|name=Tomari Nuclear Power Station}} || {{good|Suspended<ref name=fepcrestarts>{{cite web|title=Nuclear Power Plants in Japan - The Federation of Electric Power Companies of Japan(FEPC)|url=http://www.fepc.or.jp/english/nuclear/power_generation/plants/index.html|website=www.fepc.or.jp|access-date=8 May 2018|language=en}}</ref>}}
|-
| [[Tsuruga Nuclear Power Plant|Tsuruga]] || 1,160 || [[Tsuruga, Fukui|Tsuruga]], [[Fukui Prefecture|Fukui]] || {{coord|35|40|22|N|136|04|38|E|name=Tsuruga Nuclear Power Station}} || {{good|Suspended (unit 1 to be decommissioned<ref name=wnn-20170419/>)}}
|-
! Total || 39,748 || colspan=3 | 
|}

On 6 May 2011, then Prime Minister [[Naoto Kan]] requested the [[Hamaoka Nuclear Power Plant]] be shut down as an earthquake of magnitude 8.0 or higher is estimated 87% likely to hit the area within the next 30 years.<ref>[https://www.bbc.co.uk/news/world-asia-pacific-13306358 Story] at [[BBC]] News, 6 May 2011.  retrieved 8 May 2011</ref><ref>[http://www.digitaljournal.com/article/306399 Story] at Digital Journal.  retrieved 7 May 2011</ref><ref>[https://www.bloomberg.com/news/2011-05-07/chubu-electric-s-board-meets-on-possible-shutdown-of-nuclear-power-plant.html Story] at [https://www.bloomberg.com Bloomberg], 7 May 2011.  retrieved 8 May 2011]</ref> Kan wanted to avoid a possible repeat of the [[Fukushima nuclear disaster]].<ref name="Japan nuke plant suspends work"/> On 9 May 2011, Chubu Electric decided to comply with the government's request. In July 2011, a mayor in Shizuoka Prefecture and a group of residents filed a lawsuit seeking the decommissioning of the reactors at the Hamaoka nuclear power plant permanently.<ref>{{cite web |url=http://search.japantimes.co.jp/cgi-bin/nn20110701x2.html |title=Suit seeks to shut Hamaoka reactors for good |date=1 July 2011 |work=Japan Times }}</ref>

In April 2014, [[Reuters]] reported that Prime Minister [[Shinzo Abe]] favours restarting nuclear plants, but that its analysis suggests that only about one-third to two-thirds of reactors will be in a technical and economic position to restart.<ref name=jt-20140402>{{cite news |url=http://www.japantimes.co.jp/news/2014/04/02/national/only-one-third-of-nations-nuclear-reactors-may-be-restarted-analysis/ |title=Only a third of nuclear reactors may be restarted |author1=Mari Saito |author2=Aaron Sheldrick |author3=Kentaro Hamada |agency=Reuters |newspaper=The Japan Times |date=2 April 2014 |access-date=4 April 2014}}</ref>
In April 2017 the Nuclear Regulation Authority approved plans to decommission the Genkai 1, Mihama 1 and 2, Shimane 1, and Tsuruga 1 reactors.<ref name=wnn-20170419>{{cite news |url=http://www.world-nuclear-news.org/WR-Decommissioning-plans-approved-for-five-Japanese-units-1904174.html |title=Decommissioning plans approved for five Japanese units |publisher=World Nuclear News |date=19 April 2017 |access-date=24 April 2017}}</ref>

== Nuclear accidents ==
{{see also|List of Japanese nuclear incidents}}
In terms of consequences of radioactivity releases and core damage, the [[Fukushima I nuclear accidents]] in 2011 were the worst experienced by the Japanese nuclear industry, in addition to ranking among the worst [[List of civilian nuclear accidents|civilian nuclear accidents]], though no fatalities were caused and no serious exposure of radiation to workers occurred. 
The [[Tokaimura]] reprocessing plant fire in 1999 had 2 worker deaths, one more was exposed to radiation levels above legal limits, and over 660 others received detectable radiation doses but within permissible levels, well below the threshold to affect human health. The [[Mihama Nuclear Power Plant]] experienced a steam explosion in one of the turbine buildings in 2004 where five workers were killed and six injured.<ref name=KEPCO-20070207>{{cite web |url=http://www.kepco.co.jp/english/notice/070207.html |title=Restarting Commercial Operation of Mihama Nuclear Power Plant Unit 3 |publisher=KEPCO |date=7 February 2007 |access-date=16 April 2014 |url-status=dead |archive-url=https://web.archive.org/web/20140416183322/http://www.kepco.co.jp/english/notice/070207.html |archive-date=16 April 2014 }}</ref>

=== 2011 accidents ===
[[File:JAPAN EARTHQUAKE 20110311.svg|thumb|A map showing [[epicenter]] of earthquake and position of nuclear power plants]]
There have been many nuclear shutdowns, failures, and three partial [[Nuclear meltdown|meltdowns]] which were triggered by the [[2011 Tōhoku earthquake and tsunami]].

{| class="wikitable"
|-
!Plant description
!Accident descriptions
|-
| [[Fukushima Daiichi Nuclear Power Plant]]
|
* [[Fukushima Daiichi nuclear disaster]]
* [[Timeline of the Fukushima Daiichi nuclear disaster]]
|-
| [[Fukushima II Nuclear Power Plant]]
|[[Fukushima II Nuclear Power Plant#2011 earthquake and tsunami|Fukushima II nuclear accidents]]
|-
| [[Onagawa Nuclear Power Plant]]
| [[Onagawa Nuclear Power Plant#2011|Onagawa Nuclear Power Plant incidents]]
|-
| [[Tōkai Nuclear Power Plant]]
| [[Tōkai Nuclear Power Plant#Incidents|Tōkai Nuclear Power Plant incidents]]
|-
| [[Rokkasho Reprocessing Plant]]
| [[Rokkasho Reprocessing Plant#2011 Tōhoku earthquake and tsunami|Rokkasho Reprocessing Plant incidents]]
|}

=== Fukushima Daiichi nuclear disaster ===
According to the Federation of Electric Power Companies of Japan, "by April 27 approximately 55 percent of the fuel in reactor unit 1 had melted, along with 35 percent of the fuel in unit 2, and 30 percent of the fuel in unit 3; and overheated spent fuels in the storage pools of units 3 and 4 probably were also damaged".<ref name=bas2011>{{cite web |url=http://www.thebulletin.org/web-edition/features/five-steps-to-prevent-another-fukushima |title=Five steps to prevent another Fukushima |author= Jungmin Kang |date=4 May 2011 |work=Bulletin of the Atomic Scientists }}</ref> The accident exceeds the 1979 [[Three Mile Island accident]] in seriousness, and is comparable to the 1986 [[Chernobyl disaster]].<ref name=bas2011/> ''The Economist'' reports that the Fukushima disaster is "a bit like three Three Mile Islands in a row, with added damage in the spent-fuel stores",<ref name=econ2011>{{cite news |url=http://www.economist.com/node/18441163 |title=Nuclear power: When the steam clears |date=24 March 2011 |newspaper=The Economist }}</ref> and that there will be ongoing impacts:
<blockquote>
Years of clean-up will drag into decades. A permanent exclusion zone could end up stretching beyond the plant’s perimeter. Seriously exposed workers may be at increased risk of cancers for the rest of their lives...<ref name=econ2011/>
</blockquote>
On 24 March 2011, Japanese officials announced that "radioactive iodine-131 exceeding safety limits for infants had been detected at 18 water-purification plants in Tokyo and five other prefectures". Officials said also that the fallout from the Dai-ichi plant is "hindering search efforts for victims from the March 11 earthquake and tsunami".<ref>{{cite web |url=http://content.usatoday.com/communities/ondeadline/post/2011/03/report-radioactive-emissions-from-japan-plant-approach-chernobyl-levels/1 |title=Report: Emissions from Japan plant approach Chernobyl levels |author=Michael Winter |date=24 March 2011 |work=USA Today }}</ref>

Problems in stabilizing the [[Fukushima Daiichi nuclear power plant]] have hardened attitudes to [[nuclear power]]. As of June 2011, "more than 80 percent of Japanese now say they are [[anti-nuclear]] and distrust government information on [[radiation]]".<ref name=refuse2011/> The ongoing Fukushima crisis may spell the end of nuclear power in Japan, as "citizen opposition grows and local authorities refuse permission to restart reactors that have undergone safety checks". Local authorities are skeptical that sufficient safety measures have been taken and are reticent to give their permission – now required by law – to bring suspended nuclear reactors back online.<ref name="refuse2011"/><ref>Johnston, Eric, "[http://search.japantimes.co.jp/cgi-bin/nn20110922x3.html Current nuclear debate to set nation's course for decades]", ''[[Japan Times]]'', 23 September 2011, p. 1.</ref>

Two government advisers have said that "Japan's safety review of nuclear reactors after the Fukushima disaster is based on faulty criteria and many people involved have conflicts of interest". Hiromitsu Ino, Professor Emeritus at the University of Tokyo, says
"The whole process being undertaken is exactly the same as that used previous to the Fukushima Dai-Ichi accident, even though the accident showed all these guidelines and categories to be insufficient".<ref>{{cite web |url=http://news.businessweek.com/article.asp?documentKey=1376-LYG9UU6K50XS01-1T2KDJMKSDHCGQ4C640BU0QC83 |title=Japan Post-Fukushima Reactor Checks 'Insufficient,' Advisers Say |date=27 January 2012 |work=Businessweek |url-status=dead |archive-url=https://web.archive.org/web/20120214001411/http://news.businessweek.com/article.asp?documentKey=1376-LYG9UU6K50XS01-1T2KDJMKSDHCGQ4C640BU0QC83 |archive-date=14 February 2012 }}</ref>

In 2012, former prime minister [[Naoto Kan]] was interviewed about the Fukushima nuclear disaster, and has said that at one point Japan faced a situation where there was a chance that people might not be able to live in the capital zone including Tokyo and would have to evacuate. He says he is haunted by the specter of an even bigger nuclear crisis forcing tens of millions of people to flee Tokyo and threatening the nation's existence. "If things had reached that level, not only would the public have had to face hardships but Japan's very existence would have been in peril".<ref name=k12/> That convinced Kan to "declare the need for Japan to end its reliance on atomic power and promote renewable sources of energy such solar that have long taken a back seat in the resource-poor country's energy mix".<ref name=k12>{{cite web |url=https://www.reuters.com/article/us-japan-kan-idUSTRE81G08P20120217 |title=Nuclear crisis turns Japan ex-PM Kan into energy apostle |author1=Linda Sieg  |author2=Yoko Kubota  |name-list-style=amp |date=17 February 2012 |work=Reuters }}</ref>

=== Other accidents ===
{{Main|List of nuclear power accidents by country}}
{{See also|Lists of nuclear disasters and radioactive incidents}}

Other accidents of note include:<ref name=bks>[[Benjamin K. Sovacool]]. A Critical Evaluation of Nuclear Power and Renewable Electricity in Asia, ''Journal of Contemporary Asia'', Vol. 40, No. 3, August 2010, pp. 380.</ref>
* 1981: Almost 300 workers were exposed to excessive levels of radiation after a fuel rod ruptured during repairs at the [[Tsuruga Nuclear Power Plant]].<ref name=bks/>
* December 1995: The fast breeder [[Monju Nuclear Power Plant]] sodium leak.<ref name=bks/> State-run operator Donen was found to have concealed videotape footage that showed extensive damage to the reactor.<ref name=alook>{{cite news |url=http://www.businessweek.com/ap/financialnews/D9M0VHR82.htm |archive-url=https://web.archive.org/web/20110321175822/http://www.businessweek.com/ap/financialnews/D9M0VHR82.htm |url-status=dead |archive-date=21 March 2011 |title=A look at Japan's history of nuclear power trouble |agency=Associated Press |date=17 March 2011 |work=Bloomberg Businessweek }} For background on Japan's nuclear development, see [http://www.politics.ubc.ca/fileadmin/user_upload/poli_sci/Faculty/dauvergne/AsianSurvey1993.pdf Peter Dauvergne, "Nuclear Power Development in Japan: 'Outside Forces' and the Politics of Reciprocal Consent," ''Asian Survey'' 33 (June 1993), pp. 576-591.] {{Webarchive|url=https://web.archive.org/web/20120506192323/http://www.politics.ubc.ca/fileadmin/user_upload/poli_sci/Faculty/dauvergne/AsianSurvey1993.pdf |date=6 May 2012 }}</ref>
* March 1997: The [[Tokaimura]] nuclear reprocessing plant fire and explosion, northeast of Tokyo. 37 workers were exposed to low doses of radiation. Donen later acknowledged it had initially suppressed information about the fire.<ref name=bks/><ref name=alook/>
* 1999: A fuel loading system malfunctioned at a nuclear plant in the Fukui Prefecture and set off an uncontrolled nuclear reaction and explosion.<ref name=bks/>
* September 1999: The [[criticality accident]] at the [[Tokaimura nuclear accident|Tokai fuel fabrication facility]].<ref name=bks/> Hundreds of people were exposed to radiation, three workers received doses above legal limits of whom two later died.<ref name=alook/>
* 2000: Three TEPCO executives were forced to quit after the company in 1989 ordered an employee to edit out footage showing cracks in nuclear plant steam pipes in video being submitted to regulators.<ref name=alook/>
* August 2002: a widespread falsification scandal starting in that led to the shut down of all [[Tokyo Electric Power Company]]’s 17 nuclear reactors; Tokyo Electric's officials had falsified inspection records and attempted to hide cracks in [[core shroud|reactor vessel shrouds]] in 13 of its 17 units.<ref name="mycle"/>
* 2002: Two workers were exposed to a small amount of radiation and suffered minor burns during a fire at Onagawa Nuclear Power Station in northern Japan.<ref name=alook/>	
* 2006: A small amount of radioactive steam was released at the Fukushima Dai-ichi plant and it escaped the compound.<ref name=alook/>
* 16 July 2007: A [[2007 Chūetsu offshore earthquake|severe earthquake]] (measuring 6.6 on the moment magnitude scale) hit the region where Tokyo Electric's [[Kashiwazaki-Kariwa Nuclear Power Plant]] is located and radioactive water spilled into the Sea of Japan; as of March 2009, all of the reactors remain shut down for damage verification and repairs; the plant with seven units was the largest single nuclear power station in the world.<ref name=mycle/>

== Nuclear waste disposal ==
Japanese policy is to [[Nuclear reprocessing|reprocess its spent nuclear fuel]]. Originally spent fuel was reprocessed under contract in England and France, but then the [[Rokkasho Reprocessing Plant]] was built, with operations originally expected to commence in 2007.<ref>{{cite web |publisher=Japan Nuclear Fuel Limited |title=Operational progress |date=31 March 2006 |url=http://www.jnfl.co.jp/english/progress.html |archive-url=https://web.archive.org/web/20080526080731/http://www.jnfl.co.jp/english/progress.html | archive-date=26 May 2008}}</ref> The policy to use recovered plutonium as mixed oxide ([[MOX]]) reactor fuel was questioned on economic grounds, and in 2004 it was revealed the Ministry of Economy, Trade and Industry had covered up a 1994 report indicating reprocessing spent fuel would cost four times as much as burying it.<ref>{{cite journal |title=Bursting point |date=14 August 2004 |journal=Economist |page=55}}</ref>

In 2000, a Specified Radioactive Waste Final Disposal Act called for creation of a new organization to [[High-level radioactive waste management|manage high level radioactive waste]], and later that year the Nuclear Waste Management Organization of Japan (NUMO) was established under the jurisdiction of the Ministry of Economy, Trade and Industry. NUMO is responsible for selecting a permanent [[deep geological repository]] site, construction, operation and closure of the facility for waste emplacement by 2040.<ref>{{cite journal |date=May–June 2001 |title=Japan's nuclear twilight zone |journal=Bulletin of the Atomic Scientists |issue=3 |page=58 |author1=Burnie, Shaun |author2=Smith, Aileen Mioko|volume=57 |doi=10.1080/00963402.2001.11460458 |bibcode=2001BuAtS..57c..58B |s2cid=145297278 }}</ref><ref>{{cite journal |journal=Nuclear Waste Management Organization of Japan |year=2002 |title=Open solicitation for candidate sites for safe disposal of high-level radioactive waste |location=Tokyo |url=http://www.numo.or.jp}}</ref> Site selection began in 2002 and application information was sent to 3,239 municipalities, but by 2006, no local government had volunteered to host the facility.<ref>{{harvnb|Vandenbosch|2007|p=240.|Ref=none}}</ref> [[Kōchi Prefecture]] showed interest in 2007, but its mayor resigned due to local opposition. In December 2013 the government decided to identify suitable candidate areas before approaching municipalities.<ref name=jt-20140121>{{cite news |url=http://www.japantimes.co.jp/opinion/2014/01/21/editorials/japans-nuclear-waste-problem/ |title=Japan's nuclear waste problem |newspaper=The Japan Times |date=21 January 2014 |access-date=23 January 2014}}</ref>

In 2014 the head of the [[Science Council of Japan]]’s expert panel has said Japan's seismic conditions makes it difficult to predict ground conditions over the necessary 100,000 years, so it will be impossible to convince the public of the safety of deep geological disposal.<ref name=jt-20140121/>

The cost of MOX fuel had roughly quadrupled from 1999 to 2017, creating doubts about the economics of nuclear fuel reprocessing.<ref name=jt-20171219>{{cite news |url=https://japantoday.com/category/business/japan-power-companies-face-surging-nuclear-fuel-recycling-costs |title=Japanese power companies face surging nuclear fuel recycling costs |newspaper=The Japan Times |date=19 December 2017 |access-date=19 December 2017}}</ref>
In 2018 the [[Japanese Atomic Energy Commission]] updated plutonium guidelines to try to reduce plutonium stockpiles, stipulating that the [[Rokkasho Reprocessing Plant]] should only produce the amount of plutonium required for MOX fuel for Japan's nuclear power plants.<ref name=nei-20180802>{{cite news |url=http://www.neimagazine.com/news/newsjapan-revises-plutonium-guidelines-6284647 |title=Japan revises plutonium guidelines |publisher=Nuclear Engineering International |date=2 August 2018 |access-date=2 August 2018}}</ref>

== Nuclear regulatory bodies in Japan ==
* [[Nuclear Regulation Authority]] – A nuclear safety agency under the environment ministry, created on 19 September 2012. It replaced the Nuclear and Industrial Safety Agency and the Nuclear Safety Commission.
* [[Japanese Atomic Energy Commission]] (AEC) 原子力委員会 – Now operating as a commission of inquiry to the Japanese cabinet, this organization coordinates the entire nation's plans in the area of nuclear energy.
* [[Japanese Nuclear Safety Commission|Nuclear Safety Commission]] 原子力安全委員会 – The former Japanese regulatory body for the nuclear industry.
* [[Nuclear and Industrial Safety Agency]] (NISA) 原子力安全・保安院 – A former agency that performed regulatory activities and was formed on 6 January 2001, after a reorganization of governmental agencies.

== Nuclear power companies ==

=== Electric utilities running nuclear plants ===
Japan is divided into a number of regions that each get electric service from their respective regional provider, all utilities hold a monopoly and are strictly regulated by the Japanese government. For more background information, see [[Energy in Japan]]. All regional utilities in Japan currently operate nuclear plants with the exception of the [[Okinawa Electric Power Company]]. They are also all members of the [[Federation of Electric Power Companies]] (FEPCO) industry organization. The companies are listed below.
* '''Regional electric providers'''
:*[[Hokkaidō Electric Power Company]] (HEPCO) - 北海道電力
:*[[Tōhoku Electric Power Company]] (Tōhoku Electric) - 東北電力
:*[[Tokyo Electric Power Company]] (TEPCO) - 東京電力
:*[[Chūbu Electric Power Company]] (CHUDEN) - 中部電力
:*[[Hokuriku Electric Power Company]] (RIKUDEN) - 北陸電力
:*[[Kansai Electric Power Company]] (KEPCO) - 関西電力
:*[[Chūgoku Electric Power Company]] (Energia) - 中国電力
:*[[Shikoku Electric Power Company]] (YONDEN) - 四国電力
:*[[Kyūshū Electric Power Company]] (Kyūshū Electric) - 九州電力
* '''Other companies with a stake in nuclear power'''
[[File:Electric Power Development Co., Ltd (headquarters).jpg|thumb|right|The headquarters of [[Electric Power Development Company|Electric Power Development]], or ''J-Power'', whose activities are specially directed towards R&D on new power sources.]]
:*[[Japan Atomic Energy Agency]] (JAEA) - 日本原子力研究開発機構
:*[[Japan Atomic Power Company]] (JPAC) - 日本原子力発電
::JAPC, jointly owned by several Japan's major electric utilities, was created by special provisions from the Japanese government to be the first company in Japan to run a nuclear plant. Today it still operates two separate sites.
:*[[Electric Power Development Company]] (EDPC, J-POWER) - 電源開発
::This company was created by a special law after the end of World War II, it operates a number of coal fired, hydroelectric, and wind power plants, the Ohma nuclear plant that is under construction will mark its entrance to the industry upon completion.

=== Nuclear vendors and fuel cycle companies ===
Nuclear vendors provide fuel in its fabricated form, ready to be loaded in the reactor, nuclear services, and/or manage construction of new nuclear plants. The following is an incomplete list of companies based in Japan that provide such services. The companies listed here provide fuel or services for commercial light water plants, and in addition to this, JAEA has a small [[MOX fuel]] fabrication plant. Japan operates a robust [[nuclear fuel cycle]].<ref>Nagata, Kazuaki, "[http://www.japantimes.co.jp/text/nn20120918i1.html Vicious nuclear fuel cycle proving difficult to break]", ''[[Japan Times]]'', 18 September 2012, p. 3</ref>
* Nuclear Fuel Industries (NFI) - 原子燃料工業 NFI operates nuclear fuel fabrication plants in both [[Kumatori, Osaka]] and in [[Tōkai, Ibaraki]], fabricating 284 and 200 (respectively) metric tons Uranium per year. The Tōkai site produces [[Boiling Water Reactor|BWR]], HTR, and ATR fuel while the Kumatori site produces only [[Pressurized Water Reactor|PWR]] fuel.
* [[Japan Nuclear Fuel Limited]] (JNFL, JNF) - 日本原燃 The shareholders of JNFL are the Japanese utilities. JNFL plans to open a full scale enrichment facility in [[Rokkasho, Aomori]] with a capacity of 1.5 million SWU/yr along with a MOX fuel fabrication facility. JNFL has also operated a nuclear fuel fabrication facility called Kurihama Nuclear Fuel Plant in [[Yokosuka, Kanagawa]] as GNF, producing BWR fuel.
* [[Mitsubishi Heavy Industries]] / [[Atmea]] - 三菱重工業 原子力事業本部 MHI operates a fuel manufacturing plant in [[Tōkai, Ibaraki]], and contributes many heavy industry components to construction of new nuclear plants, and has recently designed its own [[Advanced Pressurized Water Reactor|APWR]] plant type, fuel fabrication has been completely [[Pressurized Water Reactor|PWR]] fuel, though MHI sells components to BWRs as well. It was selected by the Japanese government to develop fast breeder reactor technology and formed [[Mitsubishi FBR Systems]]. MHI has also announced an alliance with [[Areva]] to form a new company called Atmea.
* Global Nuclear Fuel (GNF). GNF was formed as a joint venture with [[GE Nuclear Energy]] (GENE), [[Hitachi, Ltd.|Hitachi]], and [[Toshiba]] on 1 January 2000. GENE has since strengthened its relationship with Hitachi, forming a global nuclear alliance:
* [[GE Hitachi Nuclear Energy]] (GEH) - 日立GEニュークリア・エナジー This company was formed 1 July 2007. Its next generation reactor, the [[Economic Simplified Boiling Water Reactor|ESBWR]] has made significant progress with US regulators. Its predecessor design, the ABWR, has been approved by the UK regulator for construction in the UK, following successful completion of the generic design assessment (GDA) process in 2017.
* [[Toshiba]] - 東芝 電力システム社 原子力事業部 Toshiba has maintained a large nuclear business focused mostly on [[Boiling Water Reactors]]. With the purchase of the American [[Westinghouse Electric Company|Westinghouse]] by US$5.4 Billion in 2006, which is focused mainly on [[Pressurized Water Reactor]] technology, it increased the size of its nuclear business about twofold. On 29 March 2017 Toshiba placed Westinghouse in [[Chapter 11 bankruptcy]] because of $9 billion of losses from its nuclear reactor construction projects, mostly the construction of four [[AP1000]] reactors in the U.S.<ref name=reuters-20170324>{{cite news |url=https://www.reuters.com/article/us-toshiba-accounting-idUSKBN16V04G |title=Toshiba decides on Westinghouse bankruptcy, sees $9 billion in charges: sources |first=Taro |last=Fuse |work=Reuters |date=24 March 2017 |access-date=25 March 2017}}</ref> Toshiba still has a profitable maintenance and nuclear fuel supply business in Japan, and is a significant contractor in the Fukushima clean-up.<ref name=reuters-20170331>{{cite news |url=https://www.reuters.com/article/us-toshiba-nuclear-idUSKBN17211S |title=Big in Japan? Hope at home for Toshiba's nuclear arm after U.S. debacle |first=Aaron |last=Sheldrick |work=Reuters |date=31 March 2017 |access-date=4 April 2017}}</ref>
* Recyclable-Fuel Storage Co. A company formed by [[TEPCO]] and Japan Atomic Power Co. to build a spent nuclear fuel storage facility in [[Aomori Prefecture]].<ref>[[Kyodo News]], "[http://www.japantimes.co.jp/text/nn20120317a5.html Work resumes on Aomori atomic fuel storage site]", ''[[Japan Times]]'', 17 March 2012, p. 2.</ref>

There have been discussions between Hitachi, Mitsubishi Heavy Industries and Toshiba about possibly consolidating some of their nuclear activities.<ref name=reuters-20170331/>

== Nuclear research and professional organizations in Japan ==

=== Research organizations ===
These organizations are government-funded research organizations, though many of them have special status to give them power of administration separate from the Japanese government. Their origins date back to the [[Atomic Energy Basic Law]], but they have been reorganized several times since their inception.
* [[Japan Atomic Energy Research Institute]] (JAERI) - 日本原子力研究所  The original nuclear energy research organization established by the Japanese government under cooperation with U.S. partners.
* Atomic Fuel Corporation - 原子燃料公社  This organization was formed along with JAERI under the Atomic Energy Basic Law and was later reorganized to be PNC.
* [[Power Reactor and Nuclear Fuel Development Corporation]] (PNC) - Succeeded the AFC in 1967 in order to perform more direct construction of experimental nuclear plants, and was renamed JNC in 1998.
* [[Japan Nuclear Cycle Development Institute]] (JNC) - 核燃料サイクル開発機構 (semi-governmental agency) Was formed in 1998 as the direct successor to the PNC. This organization operated Lojo and [[Monju Nuclear Power Plant|Monju]] experimental and demonstration reactors.
* [[Japan Atomic Energy Agency]] (JAEA) - 日本原子力研究開発機構 This is the modern, currently operating primary nuclear research organization in Japan. It was formed by a merger of JAERI and JNC in 2005.

===Academic/professional organizations===
* [[Japan Atomic Industrial Forum]] (JAIF) 日本原子力産業協会 is a non-profit organization, established in 1956 to promote the peaceful use of atomic energy.<ref>{{cite web |url=http://www.jaif.or.jp/english/activities_new.html#purpose |title=Japan Atomic Industrial Forum |publisher=Jaif.or.jp |access-date=25 September 2013 |archive-url=https://web.archive.org/web/20110818031618/http://www.jaif.or.jp/english/activities_new.html#purpose |archive-date=18 August 2011 |url-status=dead }}</ref>
* The Atomic Energy Society of Japan (AESJ) 日本原子力学会 is a major academic organization in Japan focusing on all forms of nuclear power. The ''Journal of Nuclear Science and Technology'' is the academic journal run by the AESJ. It publishes English and Japanese articles, though most submissions are from Japanese research institutes, universities, and companies.<ref>{{cite web|url=http://www.aesj.or.jp/index-e.html |title=Atomic Energy Society of Japan. |publisher=Aesj.or.jp |access-date=25 September 2013}}</ref>{{Citation needed|date=March 2011}}
* Japan Nuclear Technology Institute (JANTI) 日本原子力技術協会 was established to by the nuclear power industry to support and lead that industry.<ref>{{cite web|url=http://www.gengikyo.jp/english/shokai/shoukaiindex.html |title=Japan Nuclear Technology Institute |publisher=Gengikyo.jp |access-date=25 September 2013}}</ref>
* [[Japan Electric Association]] (JEA) 日本電気協会 develops and publishes codes and guides for the Japanese nuclear power industry<ref name=cns-2007>[http://www-ns.iaea.org/downloads/ni/safety_convention/japan_report_041227.PDF Convention on Nuclear Safety; National Report of Japan for Fourth Review Meeting] Government of Japan, published September 2007, accessed 7 April 2011</ref> and is active in promoting nuclear power.<ref name=jea-work>{{in lang|ja}} [http://www.denki.or.jp/about/work.html Work] {{webarchive|url=https://web.archive.org/web/20110305032435/http://www.denki.or.jp/about/work.html |date=5 March 2011 }} Japan Electric Association, accessed 7 April 2011</ref>

=== Other proprietary organizations ===
* [[JCO (company)|JCO]]. Established in 1978 as by Sumimoto Metal Mining Co. this company did work with Uranium conversion and set up factories at the Tokai-mura site. Later, it was held solely responsible for the [[Tokaimura nuclear accident]]

==Anti-nuclear movement==
{{Main|Anti-nuclear power movement in Japan}} 
[[File:Anti-Nuclear Power Plant Rally on 19 September 2011 at Meiji Shrine Outer Garden 03.JPG|thumb|Anti-Nuclear Power Plant Rally on 19 September 2011 at [[Meiji Shrine]] complex in Tokyo. Sixty thousand people marched chanting "Sayonara nuclear power" and waving banners, to call on Japan's government to abandon nuclear power, following the Fukushima disaster.<ref name="usatoday.com"/><ref name=wompro>{{cite web |url=http://japanfocus.org/events/view/117#|title=Fukushima women against nuclear power: finding a voice from Tohoku |author=David H. Slater |date=9 November 2011 |work=The Asia-Pacific Journal }}</ref>]]
[[File:VOA Herman - 2011-04-16 anti-nuclear protests in Tokyo.jpg|thumb|Peaceful anti-nuclear protest in Tokyo, Japan, escorted by policemen, 16 April 2011.]]

Long one of the world's most committed promoters of civilian [[nuclear power]], Japan's nuclear industry was not hit as hard by the effects of the 1979 [[Three Mile Island accident]] (USA) or the 1986 [[Chernobyl disaster]] (USSR) as some other countries.  Construction of new plants continued to be strong through the 1980s and into the 1990s.  However, starting in the mid-1990s there were several nuclear related accidents and cover-ups in Japan that eroded public perception of the industry, resulting in protests and resistance to new plants.  These accidents included the [[Tokaimura nuclear accident]], the [[Mihama Nuclear Power Plant|Mihama steam explosion]], cover-ups after accidents at the [[Monju Nuclear Power Plant|Monju reactor]], and more recently the [[Kashiwazaki-Kariwa Nuclear Power Plant]] was completely shut down for 21 months following an earthquake in 2007.  While exact details may be in dispute, it is clear that the safety culture in Japan's nuclear industry has come under greater scrutiny.<ref name="Japan cancels nuclear plant"/>

The negative impact of the 2011 [[Fukushima nuclear disaster]] has changed attitudes in Japan. Political and energy experts describe "nothing short of a nationwide loss of faith, not only in Japan’s once-vaunted nuclear technology but also in the government, which many blame for allowing the accident to happen".<ref>{{cite news |url=https://www.nytimes.com/2012/03/09/world/asia/japan-shutting-down-its-nuclear-power-industry.html?ref=energyandpower |title=Japan's Nuclear Energy Industry Nears Shutdown, at Least for Now |author=Martin Fackler |date=8 March 2012 |work=New York Times }}</ref> Sixty thousand people marched in central Tokyo on 19 September 2011, chanting "Sayonara nuclear power" and waving banners, to call on Japan's government to abandon nuclear power, following the Fukushima disaster.<ref name="usatoday.com"/><ref name=wompro/> Bishop of Osaka, Michael Goro Matsuura, has called on the solidarity of Christians worldwide to support this anti-nuclear campaign.<ref name="Sean McDonagh">{{cite news |url=https://www.irishtimes.com/newspaper/opinion/2012/0306/1224312849774.html |title=After Fukushima, Vatican joins growing army of opponents of nuclear power |author=Sean McDonagh |date=6 March 2012 |newspaper=The Irish Times  }}</ref> In July 2012, 75,000 people gathered near in Tokyo for the capital's largest anti-nuclear event. Organizers and participants said such demonstrations signal a fundamental change in attitudes in a nation where relatively few have been willing to engage in political protests since the 1960s.<ref name="Mure Dickie">{{cite news |url=https://www.washingtonpost.com/world/asia_pacific/japanese-anti-nuclear-demonstrations-grow/2012/07/16/gJQAPXPgoW_story.html |title=Japanese anti-nuclear demonstrations grow |author=Mure Dickie |date=17 July 2012 |newspaper=Washington Post }}</ref>

[[Anti-nuclear]] groups include the [[Citizens' Nuclear Information Center]], [[Stop Rokkasho]], [[Hibakusha|Hidankyo]], [[Sayonara Nuclear Power Plants]], Women from Fukushima Against Nukes, and the [[Article 9 of the Japanese Constitution|Article 9 group]]. People associated with the anti-nuclear movement include: [[Jinzaburo Takagi]], [[Haruki Murakami]], [[Kenzaburō Ōe]], [[Nobuto Hosaka]], [[Mizuho Fukushima]], [[Ryuichi Sakamoto]] and [[Tetsunari Iida]].

== See also ==
* [[Energy in Japan]]
* [[Environmental issues in Japan]]
* [[Nuclear Regulation Authority]]
* [[Japan's non-nuclear weapons policy]]
* [[Japanese nuclear weapon program]]
* [[United States-Japan Joint Nuclear Energy Action Plan]]
{{Portal bar|Energy|Japan|Nuclear technology}}

== Notes ==
{{Reflist|group=lower-alpha}}

== References ==
{{reflist|colwidth=30em}}

== Further reading ==
* Bacon, Paul, and Christopher Hobson. ''Human Security and Japan's Triple Disaster: Responding to the 2011 earthquake, tsunami and Fukushima nuclear crisis'' (2014)
* Dreiling, Michael. "An Energy Industrial Complex in Post-Fukushima Japan: A Network Analysis of the Nuclear Power Industry, the State and the Media." ''XVIII ISA World Congress of Sociology'' (13–19 July 2014). Isaconf, 2014.
* Fam, Shun Deng, et al. "Post-Fukushima Japan: The continuing nuclear controversy." ''Energy Policy'' 68 (2014): 199–205.
* Jackson, Keith. "Natural Disaster and Nuclear Crisis in Japan: Response and recovery after Japan's 3/11 and After the Great East Japan Earthquake: Political and Policy Change in post-Fukushima Japan." ''Asia Pacific Business Review'' (2014): 1–9.
* Kelly, Dominic. "US Hegemony and the Origins of Japanese Nuclear Power: The Politics of Consent." ''New Political Economy'' 19.6 (2014): 819–846.
* Kinefuchi, Etsuko. "Nuclear Power for Good: Articulations in Japan's Nuclear Power Hegemony." ''Communication, Culture & Critique'' (2015).
* Kingston, Jeff. "Abe'S Nuclear Renaissance: Energy Politics in Post–3.11 Japan." ''Critical Asian Studies'' 46.3 (2014): 461–484.
* Len, Christopher, and Victor Nian. "Nuclear versus Natural Gas: An Assessment on the Drivers Influencing Japan's Energy Future." ''Energy Procedia'' 61 (2014): 194–197.
* Nian, Victor, and S. K. Chou. "The state of nuclear power two years after Fukushima{{snd}}The ASEAN perspective." ''Applied Energy'' 136 (2014): 838–848.
* Zhang, Qi, and Benjamin C. Mclellan. "Review of Japan's power generation scenarios in light of the Fukushima nuclear accident." ''[[International Journal of Energy Research]]'' 38.5 (2014): 539–550.

== External links ==
{{Commons category|Nuclear power in Japan}}
* [http://world-nuclear.org/info/inf79.html Nuclear power in Japan] on the [[World Nuclear Association]] website

{{Japan Nuclear Plants}}
{{Nuclear power by country}}
{{2011 Tōhoku earthquake and tsunami}}

{{DEFAULTSORT:Nuclear Power In Japan}}
[[Category:Nuclear power in Japan| ]]
[[Category:Nuclear accidents and incidents]]