한국전력기술

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Model	OPR1000	APR1400	APR+	Heavy water reactor
Period	1990s	2000 - 2010s	2020s	-
Capacity	700 - 1,000 MW	1,400 MW class	1,500 MW class	700 MW class
Features	Achieved 95% technological independence through a technology transfer according to a technology licensing contract; Constructed Korean standard nuclear reactor plants	3rd-generation nuclear reactor plant; Redundancy of safety systems; Core technology independence; Market-specific design	Hybrid safety design Strengthening passive safety; Equipment to respond to severe accidents; Complex modularization; Automatic load-follow operation; Strengthening economic feasibility (36 months for construction)	Use of natural uranium fuel; Fuel replacement during nuclear reactor plant operation; High convenience of replacement of nuclear reactor components
Performance	Hanul Units 3, 4, 5 & 6 Hanbit Units 5 & 6 Shin-Kori Units 1 & 2 Shin-Wolseong Units 1 & 2	Saeul Units 1, 2, 3 & 4 UAE nuclear power plant units 1, 2, 3 & 4 Shin-Hanul Units 1 & 2 Shin-Hanul Units 3 & 4 (in construction)	-	Wolseong Units 1, 2, 3 & 4
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OPR1000

OPR1000, which is touted as “the safest among the 1000 MW nuclear power plants under construction globally”, boasts optimal economic efficiency and safety by completing constant improvements of problems with the preceding units and incorporating them in the repeated designs of a total of 6 units, including Hanul Units 5 and 6 and Hanbit Units 5 and 6. It has incorporated all follow-up measures after the U.S. Three Mile Island (TMI) nuclear reactor accident and secured the highest level of safety by applying the concepts of severe accident prevention and mitigation accident. It has also applied redundancy, diversity, and independence of safety-related equipment and the safe operation principle in preparation of failure based on the concept of “Defense in depth”. Afterward, we broke away from partial design upgrades through repeated construction and performed comprehensive improvements to OPR1000 to improve its technology and economic efficiency further, resulting in the upgraded OPR1000 with superior international competitiveness. With advent of the upgraded OPR1000 to Shin-Kori Units 1 and 3 and Shin-Wolseong Units 1 and 2, KEPCO E&C has secured design performance for 12 nuclear reactor plants of the OPR1000 series.

APR1400

APR1400 is a next-generation nuclear reactor plant developed by improving OPR1000. The state-of-the-art nuclear reactor plant has increased power generation capacity from 1000 MW to 1400 MW, extending the renewal period for continuous operation from 40 to 60 years. Its strengths surpass the technological level of third-generation nuclear reactor plants developed by advanced countries. In particular, the APR1400 standard design reflects the earthquake response design that fulfills all 0.3g seismic requirements in rock and soil conditions according to the standard design comprehensive site concept for enhanced safety. Moreover, we have bolstered its ability to respond to external shocks such as fire, flood, and earthquake by introducing a four-quadrant layout design method for auxiliary buildings.

The standard design of EU-APR, the EU-export model of APR1400, acquired the EUR certificate in November 2017, and APR1400 acquired the design certificate (DC) from the U.S. Nuclear Regulatory Commission (NRC). As a result, we expect to kickstart the export of nuclear reactor plants besides the UAE.

APR+

The APR+ nuclear reactor plant was developed according to the “Nuclear Reactor Technology Development Plan” (NU-Tech 2012) to overcome the imposed restrictions on independent overseas export through complete independence of some core technologies that depend on foreign-imported technologies. Given that APR+ was developed entirely with domestic technology, it is a pure Korean model, unhampered by any obstacles to export. The development has enabled us to secure core technologies in the reactor coolant pump (RCP) man-machine interface system in the instrumentation and control system (MMIS) and core codes for nuclear reactor design, which had to rely on foreign-imported technologies for APR1400. Also, APR+ was designed to supply cooling water for up to three days even if the electricity needed for reactor cooling is cut off when the reactor suddenly shuts down.

Moreover, while the frequency of a serious accident that causes the reactor core to melt is less than once per 100,000 years for existing nuclear reactor plants, the APR+ is designed to be less than once per million years, and the basic design requirement for the cybersecurity of APR+ is subject to domestic regulations to protect the safety functions of the nuclear reactor control system from malicious cyberattacks.

In addition, major facilities such as the Main Control Room and Remote Shutdown Room, which are the brains of the reactor facility, are designed to be completely protected from large-scale external shocks such as aircraft crashes. Compared to APR1400, APR+ has 16 more nuclear fuel rods and a 30 cm larger reactor diameter. Accordingly, although the scale of APR+ power generation has increased, its efficiency has even improved. KEPCO E&C also devoted every effort into developing technologies for SC structures and composite modules, which are the key to shortening the construction period but relegated to a limited technology level. As a result, the construction period for APR+ was shortened by one year from APR1400. In addition, like a thermal power plant, it can flexibly reduce electricity production so that it can flexibly respond to ever-changing electricity demand.

Heavy water reactor

South Korea has introduced a pressurized heavy water reactor (PHWR) through a partnership with Canada-based AECL to diversify nuclear reactor types and provide a stable power supply. AECL’s CANDU nuclear reactor plant was applied to Wolseong Units 1 through 4, and KEPCO E&C participated jointly with AECL in comprehensive design and reactor system design to secure design technology and experience in the heavy-water reactor type. While KEPCO E&C'S design participation rate was around 10% for Wolseong Unit 1, it increased to 73% for Wolseong Unit 2 and 81% for Wolseong Units 3 and 4, securing design technology to design heavy-water reactor nuclear power plants independently.