The reactor problems in Japan highlight the need for the passive safety features that are built into proposed new nuclear plant designs.

A combination of extreme events led to the current predicament with the Japanese reactors. News reports indicate that “the ocean waves [generated by the post-quake tsunami] damaged generators and backup systems, harming the ability to cool the reactors.” There are also reports that a valve that was opened to reduce pressure in the reactor did not close, resulting in the loss of cooling water.  

New Generation III reactor designs, such as those from GE and Westinghouse, potentially reduce such problems. 

The new designs have “far less piping and a minimum number of valves and pumps — in one new design, for example, there are 50 percent fewer valves, 35 percent fewer pumps, 83 percent less piping, and 87 percent less control cable than in currently operating plants,” according to the NuStart Energy consortium.

Perhaps the most important change is the use passive safety features in the new designs. The new designs place water about the reactor. If a problem happens, say power is out and backup generators are not working, gravity takes over automatically flowing water into the reactor core without the need to send commands and open values.