ABWRs

The 1,356 MWe Advanced Boiling Water Reactor was jointly developed by General Electric, Hitachi, and Toshiba and BWR suppliers based on world experience with the previous BWRs. Tokyo Electric Power operates two ABWRs as units 6 and 7 of the Kashiwazaki-Kariwa Nuclear Power Station. Features of the ABWR are (Wilkins, 19921 ... 

No recirculation lines or pumps - the SBWR goes beyond the ABWR by elinunating all recirculation lines (Figure 6.1-6). 

GE 1999, The ABWR PlantGeneralDescription, GE Nuclear Energy, Palo Alto, Ch. 10. 

Advanced bioceramics, hydrothermal processing of, 14 102-104 Advanced BWR (ABWR) reactor design, 17 554... 

In the past 20 years, several advanced versions of the LWR, collectively called ALWRs, have been designed, but only one type has been built the advanced boiling water reactor (ABWR), which was built in Japan. New versions of light-water reactors are now under review for safety certification by the U.S. Nuclear Regulatory Commission (USNRC). It is expected that a high-temperature helium-cooled reactor, if built in South Africa, would become of interest to U.S. utilities and would also be reviewed by the USNRC for certification. 

The South Texas Project of two ABWRs, each of 1,200 MW, is promoted by an independent producer the NRG company. NRG has been the first unregulated company to apply for a joint construction and operation license (COL in September 2007. The project financing arrangement of the STP is made possible by different federal guarantees, which aim to alleviate the construction and regulatory risks, and also by a series of PPAs with creditworthy parties. Indeed the project will be backed by long-term fixed-price contracts with municipalities and historic suppliers. 

Fukumoto,1998) Fukumoto,A, et al, A verification and validation method and its application to digital safety systems in ABWR nuclear power plants. Nuclear Engineering and Design, V183N2, pp. 117-132, July 1998. 

In Japan, several ABWR plants are under construction now. We believe that the digital safety systems developed and validated in K-6/7 would be basically applied to these plants. 

The next version of the ABWR, the ABWR-II, is under development in Japan with the objective of reduced cost. The electric power is increased to 1700 MW(e), with commissioning of the first ABWR-II foreseen in the late 2010s. Design changes include larger fuel assemblies, passive systems, and intensified precautions against severe accidents. 

DEVELOPMENT, OPERATING EXPERIENCE AND FUTURE PLAN OF ABWR IN JAPAN... 

The development of the ABWR was adopted as one of the main tasks of Japan s Third Light Water Improvement and Standardization Program. The verification test of the internal pump was assigned by the government to the Nuclear Power Engineering Corporation and was completed. Also, various researches in connection with the ABWR were undertaken jointly by BWR utilities. 

After about 10 years study, we succeeded the development of the compact and economic plant. Milestone of ABWR development is shown in Figure 1. 

The goals of this development were (1) Enhanced safety and reliability, (2) Reduced occupational radiation exposure and radioactive waste, (3) Enhanced operability and maneuverability and (4) Improved economy. Significant improvements were induced by the adoption of the reactor internal pump, fine motion control rod drive mechanism, integral type reinforced concrete containment vessel and digital control system. Cross-section of reactor buildings for 1100MW(e)-class BWR and ABWR are described in Figure 2. 

Feasibility Study for ABWR by TEPCO, GE, Toshiba, Hitachi, ASEA-ATOM and Ansaldo-Mechanica... 

Test Development Study for ABWR by Japanese BWR Utilities, GE, Toshiba and Hitachi... 

The ABWR uses a large turbine with last stage buckets turbine is lower than that of the turbines with 41-inch resulting in an improvement of more than 25MW in buckets, together with moisture separator reheaters and has improved plant thermal efficiency from 33.4% to 34. fabricated from an ingot of 630 tons is used for the rotor... 

The construction of Kashiwazaki-Kariwa Nuclear Power Plant unit No. 6 that is the first ABWR plant in the world was started September 1991, and that of unit No. 7 was started February 1992 (Table I). We used effective construction methods, such as large block construction method and all weather construction method, to shorten the construction duration from first concrete to commercial operation start to 51.5 months (Table II). 

Now, in Taiwan, ABWR plants are under eonstruetion at Lungmen unit No. 1 and 2. In Japan, ABWR plants are under eonstruetion at Hamaoka unit No. 5 and Shika unit No. 2, and under licensing at Ohma unit No. 1. Other 8 ABWR plants are at planing stage. Subsequent ABWR Plans are listed in Table VI. 

Under the deregulatory circumstances of power market, nuclear power is required to be economically competitive for other power source. TEPCO is now progressing cost reduction of ABWR with other Japanese utilities. We adopt three approaches. The first approach is standardization, the second is design improvement that is useful for cost reduction, and the third is intelligent management. By using these measures, TEPCO intends 30% cost reduction of our next ABWR plants, compared with Kashiwazaki-Kariwa No. 6 7 of ABWR first plant. 

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