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Today, more than 400 nuclear power plants are located in 30 countries across the globe.
In December of 1942, an experiment that would change the world was taking place at the University of Chicago. After years of research and a month of construction, the world's first nuclear reactor, Chicago Pile-1, was ready for testing. Constructed of a lattice of uranium and graphite blocks stacked 57 layers high, Chicago Pile-1 bore little resemblance to today's nuclear reactors. A three person "suicide squad" was waiting to step in and shut the reactor down in case the reactor's safety features failed. Fortunately, the 50 people in attendance that day were able to share a collective sigh of relief -- as the squad was not needed. The reactor worked without a hitch, and the nuclear era was born.
Today, more than 400 nuclear power plants are located in 30 countries across the globe. Together, these plants produce 15 percent of the world's electricity and 2 percent of the world's total power supply [source: World Nuclear Association]. Nuclear power certainly has its pros and cons, but no one can deny its importance. So now that we know a little about how far nuclear power has come over the past 60 years, we're ready to take a look at the five biggest nuclear reactors on Earth, starting with a couple of reactors that might not be around much longer.
