Nuclear power offers the same or better electricity generation capabilities as coal but without the dangerous air pollution coal generation produces. Nuclear power also has advantages in terms of energy density, as a single small uranium pellet can produce the same amount of energy as an entire ton of coal. On the other hand, nuclear power brings with it the possibility of catastrophic accidents that may release radiation.
The air pollution produced by coal generation plants contains a wide variety of toxic substances, carbon dioxide and other greenhouse gases. In addition, coal ash contains radioactive materials that can cause a coal plant to produce more radiation than a nuclear reactor. Nuclear plants produce no air pollution, only releasing steam into the environment as a byproduct of power generation.
Nuclear plants produce nuclear waste. This can range from lightly irradiated safety gear and other plant equipment to highly radioactive spent fuel pellets. If this waste produces enough radioactivity to be dangerous to life, it must be stored inside protective containers until it decays and becomes inert. In some cases, this may take hundreds or thousands of years.
The chief danger of nuclear power is the potential for a catastrophic accident like the one that occurred at Fukushima in Japan. Many of the plants currently in use in 2014 were originally built decades ago and lack the safety features common in more modern designs. Newer nuclear plants are much safer, with built-in safeguards to prevent meltdowns and explosions.