<p>None of these failures has threatened the public. But the diesel generators serve the crucial function of supplying electricity to cooling systems that prevent a nuclear plant's hot, radioactive fuel from overheating, melting and potentially releasing radiation into the environment.<br /><br />That worst-case scenario happened this year when the Fukushima Dai-ichi nuclear plant in Japan lost all backup power for its cooling systems after an earthquake and tsunami.<br /><br />Experts say the failures generally are not cause for alarm. But they have prompted federal regulators to increase scrutiny at plants where the problems happen.</p>
<p>None of these failures has threatened the public. But the diesel generators serve the crucial function of supplying electricity to cooling systems that prevent a nuclear plant's hot, radioactive fuel from overheating, melting and potentially releasing radiation into the environment.<br /><br />That worst-case scenario happened this year when the Fukushima Dai-ichi nuclear plant in Japan lost all backup power for its cooling systems after an earthquake and tsunami.<br /><br />Experts say the failures generally are not cause for alarm. But they have prompted federal regulators to increase scrutiny at plants where the problems happen.</p>