Let me begin by stating that I will not make a categorical statement about the dangers of nuclear power.
Obviously, nuclear accidents anywhere should concern us. Our thoughts and prayers rest with the Japanese people as they face problems stemming from recent earthquakes and a tsunami.
Given the potential tragedies, I understand the urge to shy away from nuclear power. People believe it is the right thing to do for the right reasons. In reality, quite the opposite may be true.
If houses were catching fire spontaneously, we would figure out how to make them safe. If cars spontaneously fell apart at high speed, we would make them safe. What do we do when our fear, unfamiliarity and bafflement with nuclear power prevents us from creating much better nuclear power plant designs? We get Chernobyl, Three Mile Island and, now, the plight facing Fukushima Dai-ichi in Japan.
You see, these problem plants were, or are, based on designs from half a century ago. By the time these plants were built, they were already obsolete. Since then, few of the new designs have been built in Russia or Japan. And none of the new and much more intrinsically safe designs have gone into production in the United States.
The old designs are inherently inefficient and unstable. Their method of fission creates heat that causes even more fission. Hence, they are prone to runaway and potential meltdown, unless constantly cooled. Of course, when everything is running correctly, heat production creates steam by design to run the turbines that power 20 percent of our domestic energy needs.
If cooling pumps fail on these older designs, though, the process accelerates and meltdown can occur. In anticipation of failures, the United States mandates containment to a greater degree than was mandated in Russia or Japan in the 1970s.