Advanced Boiling Water Reactor
The Advanced Boiling Water Reactor ( ABWR abbreviation, Intermediate German BWR ) is a boiling water reactor of the third generation. The development of the reactor began in 1978. The first ABWR was taken as Block 6 in 1996 in operation in the Kashiwazaki - Kariwa nuclear power plant. It was developed in Japan by General Electric, Hitachi and Toshiba.
Technical Details
The electric generator which is operated by this nuclear reactor, having an electric power of 1300 MW. The design incorporates developments from Europe, Japan and the USA. It brings out improvements in many areas, including in the security and reliability. The control rods are moved by means of screw mechanisms, rather than by a gradual movement.
Use
The ABWR is today used four times. He is so far only used in Japanese nuclear power plants, Kashiwazaki - Kariwa plant in the (block 6 and 7), Shika (block 2) and Hamaoka (block 5). Two other reactors are in the Taiwanese nuclear power plant Lungmen (block 1 and 2) in construction. Plans for future ABWR existed for the plant in Fukushima I (Block 7 and 8) and for which facilities Higashidori (block 1), Kaminoseki (block 1 and 2), grandma and Shimane (block 3).
On 12 May 1997, the ABWR by the Nuclear Regulatory Commission (NRC ) has been certified in the U.S.. In the U.S., the nuclear power plant South Texas to get two ABWR.
Availability
The four systems in operation today ABWR plants have below average in international comparison availability, this is in "Operation Factor," the International Atomic Energy Agency documents (share of operating time with power supply of the total period of one year ). In contrast to modern printing and boiling water reactors such as the Korean OPR -1000, the convoy or the building line 72 with "Operation Factors" of about 90 %, the previously installed ABWR plants to about three to five times the non-availability. The causes lie, in addition to technical problems of the power plants themselves, even in external factors such as earthquakes and nuclear ordinances justified. Blocks 6 and 7 in Kashiwazaki Kariwa were shut down as a result of a scandal at the operating company Tepco in 2003 for review, a major earthquake in 2007 led to a prolonged shutdown, and due to the Fukushima nuclear disaster in 2011, the reactors according to the fuel change not approached again.
In the two later completed plants, the block 2 of the Shika nuclear power plant and the block 5 of the Hamaoka nuclear power plant, a turbine failure due to a design flaw was found shortly after commissioning. Both plants were throttled back on it to ensure a safe operation, and are after the complete overhaul of the turbine again can be operated at rated power. All ABWR were turned off to increase the seismic safety after the nuclear disaster in Fukushima at least until the completion of work.
Security
The most important aspect of ( which, for example, is also a member of the EPR) makes the first ABWR NPP at all to a concept of the third generation, some are passive safety features. For example, a large expansion chamber for core melt, which makes it better cooled. Furthermore, a passive containment cooling, the disadvantage of considerably smaller compared to the EPR containment ( and hence its potential earlier failure or previous shaping vents ) intends to off exists: The containment is crossed by four water pipes, where the warmth of a heated containment atmosphere by exchange in a pool of water outside the containment is to be removed; the whole is conceived as a cycle, the pump does not need it.
ABWR - II
The next generation according to the ABWR, the ABWR II, which is being developed in Japan. Development began in 1991. The ABWR II is said to have greater fuel bundle, better security features, shorter maintenance times and a flexible fuel cycle. The number of fuel rods in the reactor core is reduced in comparison to the ABWR half. The control rods are to be made larger, so that a fuel bundle in the reactor core is assigned two control rods. The ABWR - II is supposed to have a better power-down mode than its predecessor. The power is 1700 MW.
The reactor should be able to accommodate 224 fuel bundles, which provide a 18- month operation, with a burnup of 60 GWd / t. The construction costs of the reactor are just so high as that of the ABWR. By reducing the number of fuel bundle in the reactor core, the length of the maintenance time to be reduced.