Moreover, nuclear energy is also very strictly monitored by safety measures. The nuclear generator assembly is layered with a zirconium alloy and controlled by "20 control rods"(1) which can typically stop a nuclear accident. Then the cover on the nuclear core protects from emissions of radiation. Followed by the structure of the nuclear plant which is built to tolerate many natural disasters such as hurricanes, earthquakes, and tsunamis. Accidents that occurred in Chernobyl and the Three Mile Island are theoretically "impossible" under such safety measures.
(1) http://www.nei.org/howitworks/nuclearpowerplantfuel/
(2) http://www.worldclimatereport.com/index.php/2005/07/28/giving-fossil-fuels-their-due/
(3) http://www.albartlett.org/articles/art_forgotten_fundamentals_part_6.html