South Korea’s Distinct Nuclear Power Plant Design

South Korea is one of the world’s most prominent nuclear energy countries. Despite South Korea having a land area of 100,210km^2, which is about half of the United Kingdom, it already has 12 nuclear power plants. This is a significant number considering that the United Kingdom only has nine nuclear power plants. 

How do they assure the safety of nuclear power plants?  
RMBK reactor works as pumped water at the bottom of the fuel channels boils, progressing up the pressure tubes, which produce steam to turn the turbine. During this process, fuel rods are surrounded by a graphite moderator. 

Although graphite is good conductors of heat, in case of accidents, such as Chernobyl, there is a high possibility for the graphite moderator to work as kindling. This is because graphite moderators were placed right next to fuel rods, which deal with the highest temperature in the whole system. Thus, the design of the RMBK reactor escalates the possibility of further nuclear disasters.  

However, most of the nuclear power plants in Korea use pressurized water reactors. The water in the core is heated through nuclear fission, which is pumped to the following tubes where they separate water sources to create steam. 

That steam turns the turbine, which consequently turns the generator to produce electricity. During this process, the coolant water works as a moderator by making the neutrons undergo several collisions with light hydrogen atoms, causing them to lose speed. Unlike graphite, water also works as a coolant. Hence, it does not lead to further nuclear disasters.