Every gun that is made, every warship launched, every rocket fired signifies, in the final sense, a theft from those who hunger and are not fed, those who are cold and are not clothed. This world in arms is not spending money alone. It is spending the sweat of its laborers, the genius of its scientists, the hopes of its children.
- President Dwight D. Eisenhower

Tuesday, March 22, 2011

Ann Coulter

Yes, Ann... we do use radioactive elements for therapeutic purposes. That is true. Pointing out that fact in the middle of the Fukushima Dai-Ichi nuclear accident is stupid. Fukushima is leaking elements that in controlled doses can be good for people. In other words, it is polluting the environment. One apple is good for me. Getting run over by an apple cart is not good for me.

Any way, I am going to edit this blog post and rant about Pebble Bed reactors. Stay tuned.

All right, I am back! Ok, so what is a pebble bed reactor? Let's start with what it is not. It is not a light water nuclear reactor. See, how light water nuclear reactors maintain their temperature is with... light water, or regular water, as opposed to heavy water, which is water whose hydrogen atoms have neutrons. Any way, if for some reason, say a tsunami and earth quake, causes the pumps that circulate the light water to not function any more, the fuel rods start to over heat and depending on where the control rods are, can melt. Indeed, they can melt so much that the now incredibly hot material can breach the containment vessel and be released into the surrounding environment. That is a classic melt down scenario.

What a pebble bed reactor is... is melt down proof. See, it is a bed of graphite and uranium pebbles that are regulated with an inert gas. The gas rather than the fuel itself is used to heat the water to spin the steam turbines that make electricity.

Let's say an earthquake and tsunami happens at a pebble bed reactor. Well, since the plant was designed to withstand that big of an earthquake, so we're good. Oh no, the tsunami wave was really big and took out the steam turbines. Shit, we don't have any way of heating up the water! Notice that the big problem is a lack of electrical generation, not reactor regulation.

The pebbles are really hot, and they will stay really hot. They literally can't get "too hot" as long as the inert gas regulator is intact. Indeed, since these "pebbles" are about the size of bocce balls, a "scram" system can be incorporated into the design of a reactor. A "scram" system is a rapid dump of a reactor's fuel in the case of an emergency.

For some reason, the industry is in love with light water reactors. They are inherently unsafe. Pebble bed reactors are leaps and bounds safer than light water reactors. It dives me crazy.

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