Experimental 25-30 MWe Light Water Reactor

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Last Updated: September 30, 2011
Other Name: 25-30MWe 실험용경수로; Yongbyon Light Water Reactor (LWR)
Location: Bungang-jigu (분강지구), Yongbyon-gun (영변군), Pyeonganbuk-do (평안북도), North Korea
Subordinate To: Yongbyon Nuclear Research Center (영변원자력연구센터), General Department of Atomic Energy (원자력총국), Cabinet (내각)
Size: 25-30 MWe, 100MWth
Facility Status: Under Construction

Publicly-accessible imagery of the construction on the reactor became available in September 2010, though it was not clear what was being built at the time. [1] In November 2010, visiting U.S. experts described the site as a “large excavated pit... roughly 40 meters by 50 meters by 7 meters deep” where “a concrete foundation 28 meters square with round concrete preforms for the reactor containment vessel was visible.” [2] Construction apparently began in July 2010 with a target completion date of 2012, which Siegfried Hecker, one of the visiting experts, finds overly optimistic. The power level is expected to be 100 MWth with a conversion efficiency of 30 percent. The reactor will be fueled with 3.5% enriched UO2 fuel. [3] All components of the reactor will be manufactured indigenously. [4] The fuel will come from the nearby uranium enrichment facility.

In light of the nuclear crisis in Japan in March 2011, many experts have expressed concerns about the safety of this LWR. [5] Peter Hayes of the Nautilus Institute for Security & Sustainability pointed out that it is “being built without regard to the international nuclear safety standards” and that North Korea’s “old and outdated electric power grid will not be able to handle the electricity generated from it.” [6]

Analysis of satellite images in early 2012 confirmed Pyongyang’s plan to use the experimental light reactor “for electricity production,” and highlight North Korea’s determination and “impressive manufacturing capabilities, in spite of two decades of economic downturn” according to Niko Milonopoulos, Siegfried S. Hecker, and Robert Carlin. [7] However, they maintain that the reactor will most likely not be operational by the stated completion date, originally set for 2012. Furthermore, their requests for a return visit have been rejected, and “as far as [they] know, no foreigners have been granted access to the facility” since late 2010. In February 2012, satellite images acquired by the Institute for Science and International Security show construction progress in the development of additional structures around the plant. [8] The dome was placed on top of the reactor during the summer of 2012, [9] and heavy components have likely been installed. However, Olli Heinonen predicts the reactor will not be ready for commissioning for another 2-3 years. [10] Additional analysis by 38 North concurs with Heinonen’s statement, and places the operational start date sometime in 2014-15. [11]

North Korea claims the peaceful use of nuclear energy as a sovereign state, and considers its experimental reactor as a way of “solving the acute electricity problem in the DPRK.” [12]

[1] David Albright and Paul Brannan, “What is North Korea building in the area of the destroyed cooling tower? It bears watching,” ISIS Reports, 30 September 2010, http://isis-online.org.
[2] Siegfried S. Hecker, "A Return Trip to North Korea's Yongbyon Nuclear Complex," Center for International Security and Cooperation, Stanford University, 20 November 2010, http://iis-db.stanford.edu.
[3] Siegfried S. Hecker, "A Return Trip to North Korea's Yongbyon Nuclear Complex," Center for International Security and Cooperation, Stanford University, 20 November 2010, http://iis-db.stanford.edu.
[4] Siegfried S. Hecker, "Redefining denuclearization in North Korea," Bulletin of the Atomic Scientists, 20 December 2010.
[5] Ahn Jin-su, "북한 핵시설 안전성 문제: 일본 원전 사태를 계기로 살펴 본 시사점 [North Korean Nuclear Program Safety Issue: Implications in Light of Japanese Nuclear Crisis], Focus on Korean Peninsula, Institute for Far Eastern Studies, Kyungnam University, Issue 13, May/June 2011.
[6] Lee Do-young, "영변 경수로, 국제적 기준 무시한채 건설 “北서 후쿠시마 원전 같은 사고 우려 [Yongbyon LWR Being Built without Regard to International Standards; Concerns about North Korean Nuclear Accident]," Kukinews, 11 May 2011, www.kukinews.com.
[7] Niko Milonopoulos, Siegfried S. Hecker, and Robert Carlin, “North Korea from 30,000 Feet,” Bulletin of the Atomic Scientists, 6 January 2012.
[8] “Light Water Reactor Construction Progressing at Yongbyon Nuclear Site,” Institute for Science and International Security, 5 March 2012, www.isis-online.org.
[9] Mary Beth Nikitin, “North Korea’s Nuclear Weapons: Technical Issues,” Congressional Research Service, 12 February 2013, p. 7.
[10] Olli Heinonen, “The North Korean Nuclear Program in Transition,” 38 North, 26 April 2012, http://38north.org.
[11] “North Korea Resumes Construction of Light Water Reactor: Completion of Buildings May Be Near” 38 North, 16 May 2012, http://38north.org.
[12] “Statement of Spokesman for DPRK Foreign Ministry,” Rodong Sinmun, 1 December 2011, www.rodong.rep.kp.

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