Economics enhancement of APR1400 through the application of new construction methods

The development of APR1400 (formerly KNGR) project is one of Korea's national G-7 projects, sponsored by the government and KHNP (Korea Hydro and Nuclear Power Co., Ltd.). APR1400, an evolutionary standard reactor with a thermal output of 4000MWt, upgrades the safety and economic competitiveness of nuclear power, incorporating cutting-edge advanced technologies, while standing on the proven experience of Optimized Power Reactor 1000(OPR1000, formerly KSNP) design. APR1400 has been adopted as the design for Shin-Kori Units 3 and 4. APR1400 development project consisted of three phases in order to check and make only necessary adjustments at the end of each phase and the standard design certification (DC) was issued in May 2002. The project set up the top-tier requirements for the design's safety, economy, operability, maintainability, and construct ability in the earliest design stage. The requirements have been evaluated periodically during the design process, and the results of each evaluation were reflected in the final design. Shin-Kori Units 3 and 4 are the first APR1400 projects, and will be built near the Kori NPP site, where four units are currently in operation and two OPR1000 (Improved Korean Standard Nuclear Power Plant) units called Shin-Kori Units 1 and 2 are under construction. Shin-Kori Units 3 and 4 will be constructed based on APR1400 standardized design, while incorporating the site characteristics and construction and operation experiences of OPR1000. This paper describes new construction methods to improve economics and construct ability of APR1400 to meet the target schedule, which is set to 41.5 months from the first concrete pouring to the fuel loading for the Nth plant. The new construction methods consist of 'Open Top Method' for installation of major NSSS equipment, 'Large Modularization' for the Building Structures, Reactor Vessel Internals and Major Components and deck plate method, etc